linux_dsm_epyc7002/drivers/tty/serial/sirfsoc_uart.c

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/*
* Driver for CSR SiRFprimaII onboard UARTs.
*
* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/sysrq.h>
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of_gpio.h>
#include <linux/dmaengine.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include "sirfsoc_uart.h"
static unsigned int
sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count);
static unsigned int
sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count);
static struct uart_driver sirfsoc_uart_drv;
static void sirfsoc_uart_tx_dma_complete_callback(void *param);
static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port);
static void sirfsoc_uart_rx_dma_complete_callback(void *param);
static const struct sirfsoc_baudrate_to_regv baudrate_to_regv[] = {
{4000000, 2359296},
{3500000, 1310721},
{3000000, 1572865},
{2500000, 1245186},
{2000000, 1572866},
{1500000, 1245188},
{1152000, 1638404},
{1000000, 1572869},
{921600, 1114120},
{576000, 1245196},
{500000, 1245198},
{460800, 1572876},
{230400, 1310750},
{115200, 1310781},
{57600, 1310843},
{38400, 1114328},
{19200, 1114545},
{9600, 1114979},
};
static struct sirfsoc_uart_port *sirf_ports[SIRFSOC_UART_NR];
static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
{
return container_of(port, struct sirfsoc_uart_port, port);
}
static inline unsigned int sirfsoc_uart_tx_empty(struct uart_port *port)
{
unsigned long reg;
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
reg = rd_regl(port, ureg->sirfsoc_tx_fifo_status);
return (reg & ufifo_st->ff_empty(port)) ? TIOCSER_TEMT : 0;
}
static unsigned int sirfsoc_uart_get_mctrl(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
goto cts_asserted;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
SIRFUART_AFC_CTS_STATUS))
goto cts_asserted;
else
goto cts_deasserted;
} else {
if (!gpio_get_value(sirfport->cts_gpio))
goto cts_asserted;
else
goto cts_deasserted;
}
cts_deasserted:
return TIOCM_CAR | TIOCM_DSR;
cts_asserted:
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
}
static void sirfsoc_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
unsigned int assert = mctrl & TIOCM_RTS;
unsigned int val = assert ? SIRFUART_AFC_CTRL_RX_THD : 0x0;
unsigned int current_val;
if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
return;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
current_val = rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0xFF;
val |= current_val;
wr_regl(port, ureg->sirfsoc_afc_ctrl, val);
} else {
if (!val)
gpio_set_value(sirfport->rts_gpio, 1);
else
gpio_set_value(sirfport->rts_gpio, 0);
}
}
static void sirfsoc_uart_stop_tx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (sirfport->tx_dma_chan) {
if (sirfport->tx_dma_state == TX_DMA_RUNNING) {
dmaengine_pause(sirfport->tx_dma_chan);
sirfport->tx_dma_state = TX_DMA_PAUSE;
} else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_txfifo_empty_en);
}
} else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_txfifo_empty_en);
}
}
static void sirfsoc_uart_tx_with_dma(struct sirfsoc_uart_port *sirfport)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct circ_buf *xmit = &port->state->xmit;
unsigned long tran_size;
unsigned long tran_start;
unsigned long pio_tx_size;
tran_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
tran_start = (unsigned long)(xmit->buf + xmit->tail);
if (uart_circ_empty(xmit) || uart_tx_stopped(port) ||
!tran_size)
return;
if (sirfport->tx_dma_state == TX_DMA_PAUSE) {
dmaengine_resume(sirfport->tx_dma_chan);
return;
}
if (sirfport->tx_dma_state == TX_DMA_RUNNING)
return;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~(uint_en->sirfsoc_txfifo_empty_en));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_txfifo_empty_en);
/*
* DMA requires buffer address and buffer length are both aligned with
* 4 bytes, so we use PIO for
* 1. if address is not aligned with 4bytes, use PIO for the first 1~3
* bytes, and move to DMA for the left part aligned with 4bytes
* 2. if buffer length is not aligned with 4bytes, use DMA for aligned
* part first, move to PIO for the left 1~3 bytes
*/
if (tran_size < 4 || BYTES_TO_ALIGN(tran_start)) {
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)|
SIRFUART_IO_MODE);
if (BYTES_TO_ALIGN(tran_start)) {
pio_tx_size = sirfsoc_uart_pio_tx_chars(sirfport,
BYTES_TO_ALIGN(tran_start));
tran_size -= pio_tx_size;
}
if (tran_size < 4)
sirfsoc_uart_pio_tx_chars(sirfport, tran_size);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)|
uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_txfifo_empty_en);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
} else {
/* tx transfer mode switch into dma mode */
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)&
~SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
tran_size &= ~(0x3);
sirfport->tx_dma_addr = dma_map_single(port->dev,
xmit->buf + xmit->tail,
tran_size, DMA_TO_DEVICE);
sirfport->tx_dma_desc = dmaengine_prep_slave_single(
sirfport->tx_dma_chan, sirfport->tx_dma_addr,
tran_size, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
if (!sirfport->tx_dma_desc) {
dev_err(port->dev, "DMA prep slave single fail\n");
return;
}
sirfport->tx_dma_desc->callback =
sirfsoc_uart_tx_dma_complete_callback;
sirfport->tx_dma_desc->callback_param = (void *)sirfport;
sirfport->transfer_size = tran_size;
dmaengine_submit(sirfport->tx_dma_desc);
dma_async_issue_pending(sirfport->tx_dma_chan);
sirfport->tx_dma_state = TX_DMA_RUNNING;
}
}
static void sirfsoc_uart_start_tx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (sirfport->tx_dma_chan)
sirfsoc_uart_tx_with_dma(sirfport);
else {
sirfsoc_uart_pio_tx_chars(sirfport, port->fifosize);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)|
uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_txfifo_empty_en);
}
}
static void sirfsoc_uart_stop_rx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
if (sirfport->rx_dma_chan) {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~(SIRFUART_RX_DMA_INT_EN(port, uint_en) |
uint_en->sirfsoc_rx_done_en));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
SIRFUART_RX_DMA_INT_EN(port, uint_en)|
uint_en->sirfsoc_rx_done_en);
dmaengine_terminate_all(sirfport->rx_dma_chan);
} else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~(SIRFUART_RX_IO_INT_EN(port, uint_en)));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
SIRFUART_RX_IO_INT_EN(port, uint_en));
}
}
static void sirfsoc_uart_disable_ms(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (!sirfport->hw_flow_ctrl)
return;
sirfport->ms_enabled = false;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
wr_regl(port, ureg->sirfsoc_afc_ctrl,
rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0x3FF);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~uint_en->sirfsoc_cts_en);
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_cts_en);
} else
disable_irq(gpio_to_irq(sirfport->cts_gpio));
}
static irqreturn_t sirfsoc_uart_usp_cts_handler(int irq, void *dev_id)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
struct uart_port *port = &sirfport->port;
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_lock(&port->lock);
if (gpio_is_valid(sirfport->cts_gpio) && sirfport->ms_enabled)
uart_handle_cts_change(port,
!gpio_get_value(sirfport->cts_gpio));
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
static void sirfsoc_uart_enable_ms(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (!sirfport->hw_flow_ctrl)
return;
sirfport->ms_enabled = true;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
wr_regl(port, ureg->sirfsoc_afc_ctrl,
rd_regl(port, ureg->sirfsoc_afc_ctrl) |
SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
| uint_en->sirfsoc_cts_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_cts_en);
} else
enable_irq(gpio_to_irq(sirfport->cts_gpio));
}
static void sirfsoc_uart_break_ctl(struct uart_port *port, int break_state)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
unsigned long ulcon = rd_regl(port, ureg->sirfsoc_line_ctrl);
if (break_state)
ulcon |= SIRFUART_SET_BREAK;
else
ulcon &= ~SIRFUART_SET_BREAK;
wr_regl(port, ureg->sirfsoc_line_ctrl, ulcon);
}
}
static unsigned int
sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
unsigned int ch, rx_count = 0;
struct tty_struct *tty;
tty = tty_port_tty_get(&port->state->port);
if (!tty)
return -ENODEV;
while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
ufifo_st->ff_empty(port))) {
ch = rd_regl(port, ureg->sirfsoc_rx_fifo_data) |
SIRFUART_DUMMY_READ;
if (unlikely(uart_handle_sysrq_char(port, ch)))
continue;
uart_insert_char(port, 0, 0, ch, TTY_NORMAL);
rx_count++;
if (rx_count >= max_rx_count)
break;
}
sirfport->rx_io_count += rx_count;
port->icount.rx += rx_count;
tty: serial: sirfsoc: drop uart_port->lock before calling tty_flip_buffer_push() The current driver triggers a lockdep warning for if tty_flip_buffer_push() is called with uart_port->lock locked. This never shows up on UP kernels and comes up only on SMP kernels. Crash looks like this (produced with samsung.c driver): ----- [<c0014d58>] (unwind_backtrace+0x0/0xf8) from [<c0011908>] (show_stack+0x10/0x14) [<c0011908>] (show_stack+0x10/0x14) from [<c035da34>] (dump_stack+0x6c/0xac) [<c035da34>] (dump_stack+0x6c/0xac) from [<c01b59ac>] (do_raw_spin_unlock+0xc4/0xd8) [<c01b59ac>] (do_raw_spin_unlock+0xc4/0xd8) from [<c03627e4>] (_raw_spin_unlock_irqrestore+0xc/0) [<c03627e4>] (_raw_spin_unlock_irqrestore+0xc/0x38) from [<c020a1a8>] (s3c24xx_serial_rx_chars+0) [<c020a1a8>] (s3c24xx_serial_rx_chars+0x12c/0x260) from [<c020aae8>] (s3c64xx_serial_handle_irq+) [<c020aae8>] (s3c64xx_serial_handle_irq+0x48/0x60) from [<c006aaa0>] (handle_irq_event_percpu+0x) [<c006aaa0>] (handle_irq_event_percpu+0x50/0x194) from [<c006ac20>] (handle_irq_event+0x3c/0x5c) [<c006ac20>] (handle_irq_event+0x3c/0x5c) from [<c006d864>] (handle_fasteoi_irq+0x80/0x13c) [<c006d864>] (handle_fasteoi_irq+0x80/0x13c) from [<c006a4a4>] (generic_handle_irq+0x20/0x30) [<c006a4a4>] (generic_handle_irq+0x20/0x30) from [<c000f454>] (handle_IRQ+0x38/0x94) [<c000f454>] (handle_IRQ+0x38/0x94) from [<c0008538>] (gic_handle_irq+0x34/0x68) [<c0008538>] (gic_handle_irq+0x34/0x68) from [<c00123c0>] (__irq_svc+0x40/0x70) Exception stack(0xc04cdf70 to 0xc04cdfb8) df60: 00000000 00000000 0000166e 00000000 df80: c04cc000 c050278f c050278f 00000001 c04d444c 410fc0f4 c03649b0 00000000 dfa0: 00000001 c04cdfb8 c000f758 c000f75c 60070013 ffffffff [<c00123c0>] (__irq_svc+0x40/0x70) from [<c000f75c>] (arch_cpu_idle+0x28/0x30) [<c000f75c>] (arch_cpu_idle+0x28/0x30) from [<c0054888>] (cpu_startup_entry+0x5c/0x148) [<c0054888>] (cpu_startup_entry+0x5c/0x148) from [<c0497aa4>] (start_kernel+0x334/0x38c) BUG: spinlock lockup suspected on CPU#0, kworker/0:1/360 lock: s3c24xx_serial_ports+0x1d8/0x370, .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1 CPU: 0 PID: 360 Comm: kworker/0:1 Not tainted 3.11.0-rc6-next-20130819-00003-g75485f1 #2 Workqueue: events flush_to_ldisc [<c0014d58>] (unwind_backtrace+0x0/0xf8) from [<c0011908>] (show_stack+0x10/0x14) [<c0011908>] (show_stack+0x10/0x14) from [<c035da34>] (dump_stack+0x6c/0xac) [<c035da34>] (dump_stack+0x6c/0xac) from [<c01b581c>] (do_raw_spin_lock+0x100/0x17c) [<c01b581c>] (do_raw_spin_lock+0x100/0x17c) from [<c03628a0>] (_raw_spin_lock_irqsave+0x20/0x28) [<c03628a0>] (_raw_spin_lock_irqsave+0x20/0x28) from [<c0203224>] (uart_start+0x18/0x34) [<c0203224>] (uart_start+0x18/0x34) from [<c01ef890>] (__receive_buf+0x4b4/0x738) [<c01ef890>] (__receive_buf+0x4b4/0x738) from [<c01efb44>] (n_tty_receive_buf2+0x30/0x98) [<c01efb44>] (n_tty_receive_buf2+0x30/0x98) from [<c01f2ba8>] (flush_to_ldisc+0xec/0x138) [<c01f2ba8>] (flush_to_ldisc+0xec/0x138) from [<c0031af0>] (process_one_work+0xfc/0x348) [<c0031af0>] (process_one_work+0xfc/0x348) from [<c0032138>] (worker_thread+0x138/0x37c) [<c0032138>] (worker_thread+0x138/0x37c) from [<c0037a7c>] (kthread+0xa4/0xb0) [<c0037a7c>] (kthread+0xa4/0xb0) from [<c000e5f8>] (ret_from_fork+0x14/0x3c) ----- Release the port lock before calling tty_flip_buffer_push() and reacquire it after the call. Similar stuff was already done for few other drivers in the past, like: commit 2389b272168ceec056ca1d8a870a97fa9c26e11a Author: Thomas Gleixner <tglx@linutronix.de> Date: Tue May 29 21:53:50 2007 +0100 [ARM] 4417/1: Serial: Fix AMBA drivers locking Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-19 21:44:28 +07:00
return rx_count;
}
static unsigned int
sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
struct circ_buf *xmit = &port->state->xmit;
unsigned int num_tx = 0;
while (!uart_circ_empty(xmit) &&
!(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_full(port)) &&
count--) {
wr_regl(port, ureg->sirfsoc_tx_fifo_data,
xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
num_tx++;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
return num_tx;
}
static void sirfsoc_uart_tx_dma_complete_callback(void *param)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
struct uart_port *port = &sirfport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_lock_irqsave(&port->lock, flags);
xmit->tail = (xmit->tail + sirfport->transfer_size) &
(UART_XMIT_SIZE - 1);
port->icount.tx += sirfport->transfer_size;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (sirfport->tx_dma_addr)
dma_unmap_single(port->dev, sirfport->tx_dma_addr,
sirfport->transfer_size, DMA_TO_DEVICE);
sirfport->tx_dma_state = TX_DMA_IDLE;
sirfsoc_uart_tx_with_dma(sirfport);
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock_irqrestore(&port->lock, flags);
}
static void sirfsoc_uart_insert_rx_buf_to_tty(
struct sirfsoc_uart_port *sirfport, int count)
{
struct uart_port *port = &sirfport->port;
struct tty_port *tport = &port->state->port;
int inserted;
inserted = tty_insert_flip_string(tport,
sirfport->rx_dma_items[sirfport->rx_completed].xmit.buf, count);
port->icount.rx += inserted;
}
static void sirfsoc_rx_submit_one_dma_desc(struct uart_port *port, int index)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
sirfport->rx_dma_items[index].xmit.tail =
sirfport->rx_dma_items[index].xmit.head = 0;
sirfport->rx_dma_items[index].desc =
dmaengine_prep_slave_single(sirfport->rx_dma_chan,
sirfport->rx_dma_items[index].dma_addr, SIRFSOC_RX_DMA_BUF_SIZE,
DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
if (!sirfport->rx_dma_items[index].desc) {
dev_err(port->dev, "DMA slave single fail\n");
return;
}
sirfport->rx_dma_items[index].desc->callback =
sirfsoc_uart_rx_dma_complete_callback;
sirfport->rx_dma_items[index].desc->callback_param = sirfport;
sirfport->rx_dma_items[index].cookie =
dmaengine_submit(sirfport->rx_dma_items[index].desc);
dma_async_issue_pending(sirfport->rx_dma_chan);
}
static void sirfsoc_rx_tmo_process_tl(unsigned long param)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
unsigned int count;
unsigned long flags;
struct dma_tx_state tx_state;
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_lock_irqsave(&port->lock, flags);
while (DMA_COMPLETE == dmaengine_tx_status(sirfport->rx_dma_chan,
sirfport->rx_dma_items[sirfport->rx_completed].cookie, &tx_state)) {
sirfsoc_uart_insert_rx_buf_to_tty(sirfport,
SIRFSOC_RX_DMA_BUF_SIZE);
sirfport->rx_completed++;
sirfport->rx_completed %= SIRFSOC_RX_LOOP_BUF_CNT;
}
count = CIRC_CNT(sirfport->rx_dma_items[sirfport->rx_issued].xmit.head,
sirfport->rx_dma_items[sirfport->rx_issued].xmit.tail,
SIRFSOC_RX_DMA_BUF_SIZE);
if (count > 0)
sirfsoc_uart_insert_rx_buf_to_tty(sirfport, count);
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFUART_IO_MODE);
serial: sirf: fix kernel panic caused by unpaired spinlock commit 8b9ade9f74f8a279 coming from Viresh Kumar "tty: serial: sirfsoc: drop uart_port->lock before calling tty_flip_buffer_push()" broke sirfsoc uart driver by knic: [ 5.129122] BUG: spinlock already unlocked on CPU#0, ip6tables/1331 [ 5.132554] lock: sirfsoc_uart_ports+0x4/0x8a0, .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1 [ 5.141651] CPU: 0 PID: 1331 Comm: ip6tables Tainted: G W O 3.10.16 #3 [ 5.148866] [<c0013528>] (unwind_backtrace+0x0/0xe0) from [<c0010e70>] (show_stack+0x10/0x14) [ 5.157362] [<c0010e70>] (show_stack+0x10/0x14) from [<c01a5e68>] (do_raw_spin_unlock+0x40/0xc8) [ 5.166125] [<c01a5e68>] (do_raw_spin_unlock+0x40/0xc8) from [<c03ff8b4>] (_raw_spin_unlock+0x8/0x40) [ 5.175322] [<c03ff8b4>] (_raw_spin_unlock+0x8/0x40) from [<c0203fcc>] (sirfsoc_uart_pio_rx_chars+0xa4/0xc0) [ 5.185120] [<c0203fcc>] (sirfsoc_uart_pio_rx_chars+0xa4/0xc0) from [<c0204fb8>] (sirfsoc_rx_tmo_process_tl+0xdc/0x1e0) [ 5.195875] [<c0204fb8>] (sirfsoc_rx_tmo_process_tl+0xdc/0x1e0) from [<c0024b50>] (tasklet_action+0x8c/0xec) [ 5.205673] [<c0024b50>] (tasklet_action+0x8c/0xec) from [<c00242a8>] (__do_softirq+0xec/0x1d4) [ 5.214347] [<c00242a8>] (__do_softirq+0xec/0x1d4) from [<c0024428>] (do_softirq+0x48/0x54) [ 5.222674] [<c0024428>] (do_softirq+0x48/0x54) from [<c0024690>] (irq_exit+0x74/0xc0) [ 5.230573] [<c0024690>] (irq_exit+0x74/0xc0) from [<c000e1e8>] (handle_IRQ+0x6c/0x90) [ 5.238465] [<c000e1e8>] (handle_IRQ+0x6c/0x90) from [<c000d500>] (__irq_svc+0x40/0x70) [ 5.246446] [<c000d500>] (__irq_svc+0x40/0x70) from [<c0092e7c>] (mark_page_accessed+0xc/0x68) [ 5.255034] [<c0092e7c>] (mark_page_accessed+0xc/0x68) from [<c00a2a4c>] (unmap_single_vma+0x3bc/0x550) [ 5.264402] [<c00a2a4c>] (unmap_single_vma+0x3bc/0x550) from [<c00a3b4c>] (unmap_vmas+0x44/0x54) [ 5.273164] [<c00a3b4c>] (unmap_vmas+0x44/0x54) from [<c00a81a8>] (exit_mmap+0xc4/0x1e0) [ 5.281233] [<c00a81a8>] (exit_mmap+0xc4/0x1e0) from [<c001bb78>] (mmput+0x3c/0xdc) [ 5.288868] [<c001bb78>] (mmput+0x3c/0xdc) from [<c0021b0c>] (do_exit+0x30c/0x828) [ 5.296413] [<c0021b0c>] (do_exit+0x30c/0x828) from [<c0022dac>] (do_group_exit+0x4c/0xb0) [ 5.304653] [<c0022dac>] (do_group_exit+0x4c/0xb0) from [<c0022e20>] (__wake_up_parent+0x0/0x18) Root cause: the commit dropped uart_port->lock before calling tty_flip_buffer_push(), but in sirfsoc-uart, sirfsoc_uart_pio_rx_chars() can be called by sirfsoc_rx_tmo_process_tl(). here uart_port->lock has not been taken yet. so that caused unpaired lock/unlock. Solution: This patch is doing a quick fix for that, it adds spin_lock/unlock(&port->lock) protect to sirfsoc_uart_pio_rx_chars() in sirfsoc_rx_tmo_process_tl() to keep spin_lock/unlock in pair. Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Cc: stable <stable@vger.kernel.org> # 3.12 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-27 13:23:39 +07:00
sirfsoc_uart_pio_rx_chars(port, 4 - sirfport->rx_io_count);
if (sirfport->rx_io_count == 4) {
sirfport->rx_io_count = 0;
wr_regl(port, ureg->sirfsoc_int_st_reg,
uint_st->sirfsoc_rx_done);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~(uint_en->sirfsoc_rx_done_en));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_rx_done_en);
sirfsoc_uart_start_next_rx_dma(port);
} else {
wr_regl(port, ureg->sirfsoc_int_st_reg,
uint_st->sirfsoc_rx_done);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) |
(uint_en->sirfsoc_rx_done_en));
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_rx_done_en);
}
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock_irqrestore(&port->lock, flags);
tty_flip_buffer_push(&port->state->port);
}
static void sirfsoc_uart_handle_rx_tmo(struct sirfsoc_uart_port *sirfport)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct dma_tx_state tx_state;
dmaengine_tx_status(sirfport->rx_dma_chan,
sirfport->rx_dma_items[sirfport->rx_issued].cookie, &tx_state);
dmaengine_terminate_all(sirfport->rx_dma_chan);
sirfport->rx_dma_items[sirfport->rx_issued].xmit.head =
SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~(uint_en->sirfsoc_rx_timeout_en));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_rx_timeout_en);
tasklet_schedule(&sirfport->rx_tmo_process_tasklet);
}
static void sirfsoc_uart_handle_rx_done(struct sirfsoc_uart_port *sirfport)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
sirfsoc_uart_pio_rx_chars(port, 4 - sirfport->rx_io_count);
if (sirfport->rx_io_count == 4) {
sirfport->rx_io_count = 0;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~(uint_en->sirfsoc_rx_done_en));
else
wr_regl(port, SIRFUART_INT_EN_CLR,
uint_en->sirfsoc_rx_done_en);
wr_regl(port, ureg->sirfsoc_int_st_reg,
uint_st->sirfsoc_rx_timeout);
sirfsoc_uart_start_next_rx_dma(port);
}
}
static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
{
unsigned long intr_status;
unsigned long cts_status;
unsigned long flag = TTY_NORMAL;
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct uart_state *state = port->state;
struct circ_buf *xmit = &port->state->xmit;
spin_lock(&port->lock);
intr_status = rd_regl(port, ureg->sirfsoc_int_st_reg);
wr_regl(port, ureg->sirfsoc_int_st_reg, intr_status);
intr_status &= rd_regl(port, ureg->sirfsoc_int_en_reg);
if (unlikely(intr_status & (SIRFUART_ERR_INT_STAT(port, uint_st)))) {
if (intr_status & uint_st->sirfsoc_rxd_brk) {
port->icount.brk++;
if (uart_handle_break(port))
goto recv_char;
}
if (intr_status & uint_st->sirfsoc_rx_oflow)
port->icount.overrun++;
if (intr_status & uint_st->sirfsoc_frm_err) {
port->icount.frame++;
flag = TTY_FRAME;
}
if (intr_status & uint_st->sirfsoc_parity_err)
flag = TTY_PARITY;
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
intr_status &= port->read_status_mask;
uart_insert_char(port, intr_status,
uint_en->sirfsoc_rx_oflow_en, 0, flag);
}
recv_char:
if ((sirfport->uart_reg->uart_type == SIRF_REAL_UART) &&
(intr_status & SIRFUART_CTS_INT_ST(uint_st)) &&
!sirfport->tx_dma_state) {
cts_status = rd_regl(port, ureg->sirfsoc_afc_ctrl) &
SIRFUART_AFC_CTS_STATUS;
if (cts_status != 0)
cts_status = 0;
else
cts_status = 1;
uart_handle_cts_change(port, cts_status);
wake_up_interruptible(&state->port.delta_msr_wait);
}
if (sirfport->rx_dma_chan) {
if (intr_status & uint_st->sirfsoc_rx_timeout)
sirfsoc_uart_handle_rx_tmo(sirfport);
if (intr_status & uint_st->sirfsoc_rx_done)
sirfsoc_uart_handle_rx_done(sirfport);
} else {
if (intr_status & SIRFUART_RX_IO_INT_ST(uint_st))
sirfsoc_uart_pio_rx_chars(port, port->fifosize);
}
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock(&port->lock);
tty_flip_buffer_push(&state->port);
spin_lock(&port->lock);
if (intr_status & uint_st->sirfsoc_txfifo_empty) {
if (sirfport->tx_dma_chan)
sirfsoc_uart_tx_with_dma(sirfport);
else {
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
spin_unlock(&port->lock);
return IRQ_HANDLED;
} else {
sirfsoc_uart_pio_tx_chars(sirfport,
port->fifosize);
if ((uart_circ_empty(xmit)) &&
(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_empty(port)))
sirfsoc_uart_stop_tx(port);
}
}
}
spin_unlock(&port->lock);
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
return IRQ_HANDLED;
}
static void sirfsoc_uart_rx_dma_complete_tl(unsigned long param)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
unsigned long flags;
struct dma_tx_state tx_state;
spin_lock_irqsave(&port->lock, flags);
while (DMA_COMPLETE == dmaengine_tx_status(sirfport->rx_dma_chan,
sirfport->rx_dma_items[sirfport->rx_completed].cookie, &tx_state)) {
sirfsoc_uart_insert_rx_buf_to_tty(sirfport,
SIRFSOC_RX_DMA_BUF_SIZE);
if (rd_regl(port, ureg->sirfsoc_int_en_reg) &
uint_en->sirfsoc_rx_timeout_en)
sirfsoc_rx_submit_one_dma_desc(port,
sirfport->rx_completed++);
else
sirfport->rx_completed++;
sirfport->rx_completed %= SIRFSOC_RX_LOOP_BUF_CNT;
}
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock_irqrestore(&port->lock, flags);
tty_flip_buffer_push(&port->state->port);
}
static void sirfsoc_uart_rx_dma_complete_callback(void *param)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
unsigned long flags;
spin_lock_irqsave(&sirfport->port.lock, flags);
sirfport->rx_issued++;
sirfport->rx_issued %= SIRFSOC_RX_LOOP_BUF_CNT;
tasklet_schedule(&sirfport->rx_dma_complete_tasklet);
serial: sirf: fix spinlock deadlock issue commit fb78b811422cd2d8c8605949cc4cc13618347ad5 provide a workaround for kernel panic, but bring potential deadlock risk. that is in sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars cpu hold uart_port->lock, if uart interrupt comes cpu enter into sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock. the patch replace spin_lock version to spin_lock_irq* version to avoid spinlock dead lock issue. let function tty_flip_buffer_push in tasklet outof spin_lock_irq* protect area to avoid add the pair of spin_lock and spin_unlock for tty_flip_buffer_push. BTW drop self defined unused spinlock protect of tx_lock/rx_lock. 56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [56274.223648] lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 [56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.35 #1 [56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from [<c00120d8>] (show_stack+0x10/0x14) [56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) [56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) [56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) [56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c) from [<c00758f4>] (handle_irq_event+0x3c/0x5c) [56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from [<c0077fa0>] (handle_level_irq+0x98/0xfc) [56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from [<c0074f44>] (generic_handle_irq+0x2c/0x3c) [56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from [<c000ef80>] (handle_IRQ+0x40/0x90) [56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) [56274.329158] [<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>] (tty_port_tty_get+0x58/0x90) [56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) [56274.349097] [<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) [56274.359853] [<c0212ef8>] (sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>] (tasklet_action+0x84/0x114) [56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from [<c0027db4>] (__do_softirq+0x120/0x200) [56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from [<c0027f44>] (do_softirq+0x54/0x5c) [56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from [<c00281ec>] (irq_exit+0x9c/0xd0) [56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from [<c000ef84>] (handle_IRQ+0x44/0x90) [56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from [<c000dc80>] (__irq_svc+0x40/0x70) [56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) [56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) [56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from [<c000f3ac>] (arch_cpu_idle+0x8/0x38) [56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from [<c0059344>] (cpu_startup_entry+0xfc/0x140) [56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from [<c04a3a54>] (start_kernel+0x2d8/0x2e4) Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-26 18:02:07 +07:00
spin_unlock_irqrestore(&sirfport->port.lock, flags);
}
/* submit rx dma task into dmaengine */
static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
int i;
sirfport->rx_io_count = 0;
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
~SIRFUART_IO_MODE);
for (i = 0; i < SIRFSOC_RX_LOOP_BUF_CNT; i++)
sirfsoc_rx_submit_one_dma_desc(port, i);
sirfport->rx_completed = sirfport->rx_issued = 0;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) |
SIRFUART_RX_DMA_INT_EN(port, uint_en));
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
SIRFUART_RX_DMA_INT_EN(port, uint_en));
}
static void sirfsoc_uart_start_rx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
sirfport->rx_io_count = 0;
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
if (sirfport->rx_dma_chan)
sirfsoc_uart_start_next_rx_dma(port);
else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) |
SIRFUART_RX_IO_INT_EN(port, uint_en));
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
SIRFUART_RX_IO_INT_EN(port, uint_en));
}
}
static unsigned int
sirfsoc_usp_calc_sample_div(unsigned long set_rate,
unsigned long ioclk_rate, unsigned long *sample_reg)
{
unsigned long min_delta = ~0UL;
unsigned short sample_div;
unsigned long ioclk_div = 0;
unsigned long temp_delta;
for (sample_div = SIRF_USP_MIN_SAMPLE_DIV;
sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
temp_delta = ioclk_rate -
(ioclk_rate + (set_rate * sample_div) / 2)
/ (set_rate * sample_div) * set_rate * sample_div;
temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
if (temp_delta < min_delta) {
ioclk_div = (2 * ioclk_rate /
(set_rate * sample_div) + 1) / 2 - 1;
if (ioclk_div > SIRF_IOCLK_DIV_MAX)
continue;
min_delta = temp_delta;
*sample_reg = sample_div;
if (!temp_delta)
break;
}
}
return ioclk_div;
}
static unsigned int
sirfsoc_uart_calc_sample_div(unsigned long baud_rate,
unsigned long ioclk_rate, unsigned long *set_baud)
{
unsigned long min_delta = ~0UL;
unsigned short sample_div;
unsigned int regv = 0;
unsigned long ioclk_div;
unsigned long baud_tmp;
int temp_delta;
for (sample_div = SIRF_MIN_SAMPLE_DIV;
sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
ioclk_div = (ioclk_rate / (baud_rate * (sample_div + 1))) - 1;
if (ioclk_div > SIRF_IOCLK_DIV_MAX)
continue;
baud_tmp = ioclk_rate / ((ioclk_div + 1) * (sample_div + 1));
temp_delta = baud_tmp - baud_rate;
temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
if (temp_delta < min_delta) {
regv = regv & (~SIRF_IOCLK_DIV_MASK);
regv = regv | ioclk_div;
regv = regv & (~SIRF_SAMPLE_DIV_MASK);
regv = regv | (sample_div << SIRF_SAMPLE_DIV_SHIFT);
min_delta = temp_delta;
*set_baud = baud_tmp;
}
}
return regv;
}
static void sirfsoc_uart_set_termios(struct uart_port *port,
struct ktermios *termios,
struct ktermios *old)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
unsigned long config_reg = 0;
unsigned long baud_rate;
unsigned long set_baud;
unsigned long flags;
unsigned long ic;
unsigned int clk_div_reg = 0;
unsigned long txfifo_op_reg, ioclk_rate;
unsigned long rx_time_out;
int threshold_div;
u32 data_bit_len, stop_bit_len, len_val;
unsigned long sample_div_reg = 0xf;
ioclk_rate = port->uartclk;
switch (termios->c_cflag & CSIZE) {
default:
case CS8:
data_bit_len = 8;
config_reg |= SIRFUART_DATA_BIT_LEN_8;
break;
case CS7:
data_bit_len = 7;
config_reg |= SIRFUART_DATA_BIT_LEN_7;
break;
case CS6:
data_bit_len = 6;
config_reg |= SIRFUART_DATA_BIT_LEN_6;
break;
case CS5:
data_bit_len = 5;
config_reg |= SIRFUART_DATA_BIT_LEN_5;
break;
}
if (termios->c_cflag & CSTOPB) {
config_reg |= SIRFUART_STOP_BIT_LEN_2;
stop_bit_len = 2;
} else
stop_bit_len = 1;
spin_lock_irqsave(&port->lock, flags);
port->read_status_mask = uint_en->sirfsoc_rx_oflow_en;
port->ignore_status_mask = 0;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en |
uint_en->sirfsoc_parity_err_en;
} else {
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en;
}
serial: Fix IGNBRK handling If IGNBRK is set without either BRKINT or PARMRK set, some uart drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the line discipline, when it should send either nothing or the TTYBREAK flag set. This happens because the read_status_mask masks out the BI condition, which uart_insert_char() then interprets as a normal 0x00 byte. SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General Terminal Interface - Input Modes, states: "If IGNBRK is set, a break condition detected on input shall be ignored; that is, not put on the input queue and therefore not read by any process." Fix read_status_mask to include the BI bit if IGNBRK is set; the lsr status retains the BI bit if a BREAK is recv'd, which is subsequently ignored in uart_insert_char() when masked with the ignore_status_mask. Affected drivers: 8250 - all serial_txx9 mfd amba-pl010 amba-pl011 atmel_serial bfin_uart dz ip22zilog max310x mxs-auart netx-serial pnx8xxx_uart pxa sb1250-duart sccnxp serial_ks8695 sirfsoc_uart st-asc vr41xx_siu zs sunzilog fsl_lpuart sunsab ucc_uart bcm63xx_uart sunsu efm32-uart pmac_zilog mpsc msm_serial m32r_sio Unaffected drivers: omap-serial rp2 sa1100 imx icom Annotated for fixes: altera_uart mcf Drivers without break detection: 21285 xilinx-uartps altera_jtaguart apbuart arc-uart clps711x max3100 uartlite msm_serial_hs nwpserial lantiq vt8500_serial Unknown: samsung mpc52xx_uart bfin_sport_uart cpm_uart/core Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-16 19:10:41 +07:00
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
port->read_status_mask |= uint_en->sirfsoc_rxd_brk_en;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_frm_err_en |
uint_en->sirfsoc_parity_err_en;
if (termios->c_cflag & PARENB) {
if (termios->c_cflag & CMSPAR) {
if (termios->c_cflag & PARODD)
config_reg |= SIRFUART_STICK_BIT_MARK;
else
config_reg |= SIRFUART_STICK_BIT_SPACE;
} else if (termios->c_cflag & PARODD) {
config_reg |= SIRFUART_STICK_BIT_ODD;
} else {
config_reg |= SIRFUART_STICK_BIT_EVEN;
}
}
} else {
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_frm_err_en;
if (termios->c_cflag & PARENB)
dev_warn(port->dev,
"USP-UART not support parity err\n");
}
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |=
uint_en->sirfsoc_rxd_brk_en;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_rx_oflow_en;
}
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= SIRFUART_DUMMY_READ;
/* Hardware Flow Control Settings */
if (UART_ENABLE_MS(port, termios->c_cflag)) {
if (!sirfport->ms_enabled)
sirfsoc_uart_enable_ms(port);
} else {
if (sirfport->ms_enabled)
sirfsoc_uart_disable_ms(port);
}
baud_rate = uart_get_baud_rate(port, termios, old, 0, 4000000);
if (ioclk_rate == 150000000) {
for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
if (baud_rate == baudrate_to_regv[ic].baud_rate)
clk_div_reg = baudrate_to_regv[ic].reg_val;
}
set_baud = baud_rate;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (unlikely(clk_div_reg == 0))
clk_div_reg = sirfsoc_uart_calc_sample_div(baud_rate,
ioclk_rate, &set_baud);
wr_regl(port, ureg->sirfsoc_divisor, clk_div_reg);
} else {
clk_div_reg = sirfsoc_usp_calc_sample_div(baud_rate,
ioclk_rate, &sample_div_reg);
sample_div_reg--;
set_baud = ((ioclk_rate / (clk_div_reg+1) - 1) /
(sample_div_reg + 1));
/* setting usp mode 2 */
len_val = ((1 << SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET) |
(1 << SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET));
len_val |= ((clk_div_reg & SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK)
<< SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_mode2, len_val);
}
if (tty_termios_baud_rate(termios))
tty_termios_encode_baud_rate(termios, set_baud, set_baud);
/* set receive timeout && data bits len */
rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_STOP);
wr_regl(port, ureg->sirfsoc_tx_fifo_op,
(txfifo_op_reg & ~SIRFUART_FIFO_START));
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
config_reg |= SIRFUART_RECV_TIMEOUT(port, rx_time_out);
wr_regl(port, ureg->sirfsoc_line_ctrl, config_reg);
} else {
/*tx frame ctrl*/
len_val = (data_bit_len - 1) << SIRFSOC_USP_TX_DATA_LEN_OFFSET;
len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
SIRFSOC_USP_TX_FRAME_LEN_OFFSET;
len_val |= ((data_bit_len - 1) <<
SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET);
len_val |= (((clk_div_reg & 0xc00) >> 10) <<
SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_tx_frame_ctrl, len_val);
/*rx frame ctrl*/
len_val = (data_bit_len - 1) << SIRFSOC_USP_RX_DATA_LEN_OFFSET;
len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
SIRFSOC_USP_RX_FRAME_LEN_OFFSET;
len_val |= (data_bit_len - 1) <<
SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET;
len_val |= (((clk_div_reg & 0xf000) >> 12) <<
SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_rx_frame_ctrl, len_val);
/*async param*/
wr_regl(port, ureg->sirfsoc_async_param_reg,
(SIRFUART_RECV_TIMEOUT(port, rx_time_out)) |
(sample_div_reg & SIRFSOC_USP_ASYNC_DIV2_MASK) <<
SIRFSOC_USP_ASYNC_DIV2_OFFSET);
}
if (sirfport->tx_dma_chan)
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_DMA_MODE);
else
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_IO_MODE);
if (sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_DMA_MODE);
else
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_IO_MODE);
/* Reset Rx/Tx FIFO Threshold level for proper baudrate */
if (set_baud < 1000000)
threshold_div = 1;
else
threshold_div = 2;
wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl,
SIRFUART_FIFO_THD(port) / threshold_div);
wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl,
SIRFUART_FIFO_THD(port) / threshold_div);
txfifo_op_reg |= SIRFUART_FIFO_START;
wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
uart_update_timeout(port, termios->c_cflag, set_baud);
sirfsoc_uart_start_rx(port);
wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
spin_unlock_irqrestore(&port->lock, flags);
}
static void sirfsoc_uart_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
if (!state)
clk_prepare_enable(sirfport->clk);
else
clk_disable_unprepare(sirfport->clk);
}
static int sirfsoc_uart_startup(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
unsigned int index = port->line;
int ret;
set_irq_flags(port->irq, IRQF_VALID | IRQF_NOAUTOEN);
ret = request_irq(port->irq,
sirfsoc_uart_isr,
0,
SIRFUART_PORT_NAME,
sirfport);
if (ret != 0) {
dev_err(port->dev, "UART%d request IRQ line (%d) failed.\n",
index, port->irq);
goto irq_err;
}
/* initial hardware settings */
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl) |
SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_tx_dma_io_len, 0);
wr_regl(port, ureg->sirfsoc_rx_dma_io_len, 0);
wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_RX_EN | SIRFUART_TX_EN);
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(port, ureg->sirfsoc_mode1,
SIRFSOC_USP_ENDIAN_CTRL_LSBF |
SIRFSOC_USP_EN);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl, SIRFUART_FIFO_THD(port));
wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl, SIRFUART_FIFO_THD(port));
if (sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_rx_fifo_level_chk,
SIRFUART_RX_FIFO_CHK_SC(port->line, 0x4) |
SIRFUART_RX_FIFO_CHK_LC(port->line, 0xe) |
SIRFUART_RX_FIFO_CHK_HC(port->line, 0x1b));
if (sirfport->tx_dma_chan) {
sirfport->tx_dma_state = TX_DMA_IDLE;
wr_regl(port, ureg->sirfsoc_tx_fifo_level_chk,
SIRFUART_TX_FIFO_CHK_SC(port->line, 0x1b) |
SIRFUART_TX_FIFO_CHK_LC(port->line, 0xe) |
SIRFUART_TX_FIFO_CHK_HC(port->line, 0x4));
}
sirfport->ms_enabled = false;
if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
sirfport->hw_flow_ctrl) {
set_irq_flags(gpio_to_irq(sirfport->cts_gpio),
IRQF_VALID | IRQF_NOAUTOEN);
ret = request_irq(gpio_to_irq(sirfport->cts_gpio),
sirfsoc_uart_usp_cts_handler, IRQF_TRIGGER_FALLING |
IRQF_TRIGGER_RISING, "usp_cts_irq", sirfport);
if (ret != 0) {
dev_err(port->dev, "UART-USP:request gpio irq fail\n");
goto init_rx_err;
}
}
enable_irq(port->irq);
return 0;
init_rx_err:
free_irq(port->irq, sirfport);
irq_err:
return ret;
}
static void sirfsoc_uart_shutdown(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg, 0);
else
wr_regl(port, SIRFUART_INT_EN_CLR, ~0UL);
free_irq(port->irq, sirfport);
if (sirfport->ms_enabled)
sirfsoc_uart_disable_ms(port);
if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
sirfport->hw_flow_ctrl) {
gpio_set_value(sirfport->rts_gpio, 1);
free_irq(gpio_to_irq(sirfport->cts_gpio), sirfport);
}
if (sirfport->tx_dma_chan)
sirfport->tx_dma_state = TX_DMA_IDLE;
}
static const char *sirfsoc_uart_type(struct uart_port *port)
{
return port->type == SIRFSOC_PORT_TYPE ? SIRFUART_PORT_NAME : NULL;
}
static int sirfsoc_uart_request_port(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_uart_param *uart_param = &sirfport->uart_reg->uart_param;
void *ret;
ret = request_mem_region(port->mapbase,
SIRFUART_MAP_SIZE, uart_param->port_name);
return ret ? 0 : -EBUSY;
}
static void sirfsoc_uart_release_port(struct uart_port *port)
{
release_mem_region(port->mapbase, SIRFUART_MAP_SIZE);
}
static void sirfsoc_uart_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
port->type = SIRFSOC_PORT_TYPE;
sirfsoc_uart_request_port(port);
}
}
static struct uart_ops sirfsoc_uart_ops = {
.tx_empty = sirfsoc_uart_tx_empty,
.get_mctrl = sirfsoc_uart_get_mctrl,
.set_mctrl = sirfsoc_uart_set_mctrl,
.stop_tx = sirfsoc_uart_stop_tx,
.start_tx = sirfsoc_uart_start_tx,
.stop_rx = sirfsoc_uart_stop_rx,
.enable_ms = sirfsoc_uart_enable_ms,
.break_ctl = sirfsoc_uart_break_ctl,
.startup = sirfsoc_uart_startup,
.shutdown = sirfsoc_uart_shutdown,
.set_termios = sirfsoc_uart_set_termios,
.pm = sirfsoc_uart_pm,
.type = sirfsoc_uart_type,
.release_port = sirfsoc_uart_release_port,
.request_port = sirfsoc_uart_request_port,
.config_port = sirfsoc_uart_config_port,
};
#ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
static int __init
sirfsoc_uart_console_setup(struct console *co, char *options)
{
unsigned int baud = 115200;
unsigned int bits = 8;
unsigned int parity = 'n';
unsigned int flow = 'n';
struct sirfsoc_uart_port *sirfport;
struct sirfsoc_register *ureg;
if (co->index < 0 || co->index >= SIRFSOC_UART_NR)
return -EINVAL;
sirfport = sirf_ports[co->index];
if (!sirfport)
return -ENODEV;
ureg = &sirfport->uart_reg->uart_reg;
if (!sirfport->port.mapbase)
return -ENODEV;
/* enable usp in mode1 register */
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(&sirfport->port, ureg->sirfsoc_mode1, SIRFSOC_USP_EN |
SIRFSOC_USP_ENDIAN_CTRL_LSBF);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
sirfport->port.cons = co;
/* default console tx/rx transfer using io mode */
sirfport->rx_dma_chan = NULL;
sirfport->tx_dma_chan = NULL;
return uart_set_options(&sirfport->port, co, baud, parity, bits, flow);
}
static void sirfsoc_uart_console_putchar(struct uart_port *port, int ch)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
while (rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_full(port))
cpu_relax();
wr_regl(port, ureg->sirfsoc_tx_fifo_data, ch);
}
static void sirfsoc_uart_console_write(struct console *co, const char *s,
unsigned int count)
{
struct sirfsoc_uart_port *sirfport = sirf_ports[co->index];
uart_console_write(&sirfport->port, s, count,
sirfsoc_uart_console_putchar);
}
static struct console sirfsoc_uart_console = {
.name = SIRFSOC_UART_NAME,
.device = uart_console_device,
.flags = CON_PRINTBUFFER,
.index = -1,
.write = sirfsoc_uart_console_write,
.setup = sirfsoc_uart_console_setup,
.data = &sirfsoc_uart_drv,
};
static int __init sirfsoc_uart_console_init(void)
{
register_console(&sirfsoc_uart_console);
return 0;
}
console_initcall(sirfsoc_uart_console_init);
#endif
static struct uart_driver sirfsoc_uart_drv = {
.owner = THIS_MODULE,
.driver_name = SIRFUART_PORT_NAME,
.nr = SIRFSOC_UART_NR,
.dev_name = SIRFSOC_UART_NAME,
.major = SIRFSOC_UART_MAJOR,
.minor = SIRFSOC_UART_MINOR,
#ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
.cons = &sirfsoc_uart_console,
#else
.cons = NULL,
#endif
};
static const struct of_device_id sirfsoc_uart_ids[] = {
{ .compatible = "sirf,prima2-uart", .data = &sirfsoc_uart,},
{ .compatible = "sirf,atlas7-uart", .data = &sirfsoc_uart},
{ .compatible = "sirf,prima2-usp-uart", .data = &sirfsoc_usp},
{}
};
MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
static int sirfsoc_uart_probe(struct platform_device *pdev)
{
struct sirfsoc_uart_port *sirfport;
struct uart_port *port;
struct resource *res;
int ret;
int i, j;
struct dma_slave_config slv_cfg = {
.src_maxburst = 2,
};
struct dma_slave_config tx_slv_cfg = {
.dst_maxburst = 2,
};
const struct of_device_id *match;
match = of_match_node(sirfsoc_uart_ids, pdev->dev.of_node);
sirfport = devm_kzalloc(&pdev->dev, sizeof(*sirfport), GFP_KERNEL);
if (!sirfport) {
ret = -ENOMEM;
goto err;
}
sirfport->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
sirf_ports[sirfport->port.line] = sirfport;
sirfport->port.iotype = UPIO_MEM;
sirfport->port.flags = UPF_BOOT_AUTOCONF;
port = &sirfport->port;
port->dev = &pdev->dev;
port->private_data = sirfport;
sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
sirfport->hw_flow_ctrl = of_property_read_bool(pdev->dev.of_node,
"sirf,uart-has-rtscts");
if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-uart"))
sirfport->uart_reg->uart_type = SIRF_REAL_UART;
if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-usp-uart")) {
sirfport->uart_reg->uart_type = SIRF_USP_UART;
if (!sirfport->hw_flow_ctrl)
goto usp_no_flow_control;
if (of_find_property(pdev->dev.of_node, "cts-gpios", NULL))
sirfport->cts_gpio = of_get_named_gpio(
pdev->dev.of_node, "cts-gpios", 0);
else
sirfport->cts_gpio = -1;
if (of_find_property(pdev->dev.of_node, "rts-gpios", NULL))
sirfport->rts_gpio = of_get_named_gpio(
pdev->dev.of_node, "rts-gpios", 0);
else
sirfport->rts_gpio = -1;
if ((!gpio_is_valid(sirfport->cts_gpio) ||
!gpio_is_valid(sirfport->rts_gpio))) {
ret = -EINVAL;
dev_err(&pdev->dev,
"Usp flow control must have cts and rts gpio");
goto err;
}
ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
"usp-cts-gpio");
if (ret) {
dev_err(&pdev->dev, "Unable request cts gpio");
goto err;
}
gpio_direction_input(sirfport->cts_gpio);
ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
"usp-rts-gpio");
if (ret) {
dev_err(&pdev->dev, "Unable request rts gpio");
goto err;
}
gpio_direction_output(sirfport->rts_gpio, 1);
}
usp_no_flow_control:
if (of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-uart"))
sirfport->is_atlas7 = true;
if (of_property_read_u32(pdev->dev.of_node,
"fifosize",
&port->fifosize)) {
dev_err(&pdev->dev,
"Unable to find fifosize in uart node.\n");
ret = -EFAULT;
goto err;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "Insufficient resources.\n");
ret = -EFAULT;
goto err;
}
tasklet_init(&sirfport->rx_dma_complete_tasklet,
sirfsoc_uart_rx_dma_complete_tl, (unsigned long)sirfport);
tasklet_init(&sirfport->rx_tmo_process_tasklet,
sirfsoc_rx_tmo_process_tl, (unsigned long)sirfport);
port->mapbase = res->start;
port->membase = devm_ioremap(&pdev->dev, res->start, resource_size(res));
if (!port->membase) {
dev_err(&pdev->dev, "Cannot remap resource.\n");
ret = -ENOMEM;
goto err;
}
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (res == NULL) {
dev_err(&pdev->dev, "Insufficient resources.\n");
ret = -EFAULT;
goto err;
}
port->irq = res->start;
sirfport->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(sirfport->clk)) {
ret = PTR_ERR(sirfport->clk);
goto err;
}
port->uartclk = clk_get_rate(sirfport->clk);
port->ops = &sirfsoc_uart_ops;
spin_lock_init(&port->lock);
platform_set_drvdata(pdev, sirfport);
ret = uart_add_one_port(&sirfsoc_uart_drv, port);
if (ret != 0) {
dev_err(&pdev->dev, "Cannot add UART port(%d).\n", pdev->id);
goto err;
}
sirfport->rx_dma_chan = dma_request_slave_channel(port->dev, "rx");
for (i = 0; sirfport->rx_dma_chan && i < SIRFSOC_RX_LOOP_BUF_CNT; i++) {
sirfport->rx_dma_items[i].xmit.buf =
dma_alloc_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
&sirfport->rx_dma_items[i].dma_addr, GFP_KERNEL);
if (!sirfport->rx_dma_items[i].xmit.buf) {
dev_err(port->dev, "Uart alloc bufa failed\n");
ret = -ENOMEM;
goto alloc_coherent_err;
}
sirfport->rx_dma_items[i].xmit.head =
sirfport->rx_dma_items[i].xmit.tail = 0;
}
if (sirfport->rx_dma_chan)
dmaengine_slave_config(sirfport->rx_dma_chan, &slv_cfg);
sirfport->tx_dma_chan = dma_request_slave_channel(port->dev, "tx");
if (sirfport->tx_dma_chan)
dmaengine_slave_config(sirfport->tx_dma_chan, &tx_slv_cfg);
return 0;
alloc_coherent_err:
for (j = 0; j < i; j++)
dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
sirfport->rx_dma_items[j].xmit.buf,
sirfport->rx_dma_items[j].dma_addr);
dma_release_channel(sirfport->rx_dma_chan);
err:
return ret;
}
static int sirfsoc_uart_remove(struct platform_device *pdev)
{
struct sirfsoc_uart_port *sirfport = platform_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_remove_one_port(&sirfsoc_uart_drv, port);
if (sirfport->rx_dma_chan) {
int i;
dmaengine_terminate_all(sirfport->rx_dma_chan);
dma_release_channel(sirfport->rx_dma_chan);
for (i = 0; i < SIRFSOC_RX_LOOP_BUF_CNT; i++)
dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
sirfport->rx_dma_items[i].xmit.buf,
sirfport->rx_dma_items[i].dma_addr);
}
if (sirfport->tx_dma_chan) {
dmaengine_terminate_all(sirfport->tx_dma_chan);
dma_release_channel(sirfport->tx_dma_chan);
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int
sirfsoc_uart_suspend(struct device *pdev)
{
struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_suspend_port(&sirfsoc_uart_drv, port);
return 0;
}
static int sirfsoc_uart_resume(struct device *pdev)
{
struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_resume_port(&sirfsoc_uart_drv, port);
return 0;
}
#endif
static const struct dev_pm_ops sirfsoc_uart_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_uart_suspend, sirfsoc_uart_resume)
};
static struct platform_driver sirfsoc_uart_driver = {
.probe = sirfsoc_uart_probe,
.remove = sirfsoc_uart_remove,
.driver = {
.name = SIRFUART_PORT_NAME,
.of_match_table = sirfsoc_uart_ids,
.pm = &sirfsoc_uart_pm_ops,
},
};
static int __init sirfsoc_uart_init(void)
{
int ret = 0;
ret = uart_register_driver(&sirfsoc_uart_drv);
if (ret)
goto out;
ret = platform_driver_register(&sirfsoc_uart_driver);
if (ret)
uart_unregister_driver(&sirfsoc_uart_drv);
out:
return ret;
}
module_init(sirfsoc_uart_init);
static void __exit sirfsoc_uart_exit(void)
{
platform_driver_unregister(&sirfsoc_uart_driver);
uart_unregister_driver(&sirfsoc_uart_drv);
}
module_exit(sirfsoc_uart_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Bin Shi <Bin.Shi@csr.com>, Rong Wang<Rong.Wang@csr.com>");
MODULE_DESCRIPTION("CSR SiRFprimaII Uart Driver");