linux_dsm_epyc7002/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
Giuseppe Cavallaro afea03656a stmmac: rework DMA bus setting and introduce new platform AXI structure
This patch restructures the DMA bus settings and this is done
by introducing a new platform structure used for programming
the AXI Bus Mode Register inside the DMA module.
This structure can be populated from device-tree as documented in the
binding txt file.

After initializing the DMA, the AXI register can be optionally tuned
for platform drivers based.
This patch also reworks some parameters to make coherent the DMA
configuration now that AXI register is introduced.
For example, the burst_len is managed by using the mentioned axi
support above; so the snps,burst-len parameter has been removed.
It makes sense to provide the AAL parameter from DT to Address-Aligned
Beats inside the Register0 and review the PBL settings when initialize
the engine.

For PCI glue, rebuilding the story of this setting, it
was added to align a configuration so not for fixing some
known problem. No issue raised after this patch.
It is safe to use the default burst length instead of
tuning it to the maximum value

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-02 14:21:30 -05:00

131 lines
4.2 KiB
C

/*******************************************************************************
This is the driver for the MAC 10/100 on-chip Ethernet controller
currently tested on all the ST boards based on STb7109 and stx7200 SoCs.
DWC Ether MAC 10/100 Universal version 4.0 has been used for developing
this code.
This contains the functions to handle the dma.
Copyright (C) 2007-2009 STMicroelectronics Ltd
This program is free software; you can redistribute it and/or modify it
under the terms and conditions of the GNU General Public License,
version 2, as published by the Free Software Foundation.
This program is distributed in the hope it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
The full GNU General Public License is included in this distribution in
the file called "COPYING".
Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
*******************************************************************************/
#include <asm/io.h>
#include "dwmac100.h"
#include "dwmac_dma.h"
static void dwmac100_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
int aal, u32 dma_tx, u32 dma_rx, int atds)
{
/* Enable Application Access by writing to DMA CSR0 */
writel(DMA_BUS_MODE_DEFAULT | (pbl << DMA_BUS_MODE_PBL_SHIFT),
ioaddr + DMA_BUS_MODE);
/* Mask interrupts by writing to CSR7 */
writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
/* RX/TX descriptor base addr lists must be written into
* DMA CSR3 and CSR4, respectively
*/
writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);
}
/* Store and Forward capability is not used at all.
*
* The transmit threshold can be programmed by setting the TTC bits in the DMA
* control register.
*/
static void dwmac100_dma_operation_mode(void __iomem *ioaddr, int txmode,
int rxmode, int rxfifosz)
{
u32 csr6 = readl(ioaddr + DMA_CONTROL);
if (txmode <= 32)
csr6 |= DMA_CONTROL_TTC_32;
else if (txmode <= 64)
csr6 |= DMA_CONTROL_TTC_64;
else
csr6 |= DMA_CONTROL_TTC_128;
writel(csr6, ioaddr + DMA_CONTROL);
}
static void dwmac100_dump_dma_regs(void __iomem *ioaddr)
{
int i;
pr_debug("DWMAC 100 DMA CSR\n");
for (i = 0; i < 9; i++)
pr_debug("\t CSR%d (offset 0x%x): 0x%08x\n", i,
(DMA_BUS_MODE + i * 4),
readl(ioaddr + DMA_BUS_MODE + i * 4));
pr_debug("\tCSR20 (0x%x): 0x%08x, CSR21 (0x%x): 0x%08x\n",
DMA_CUR_TX_BUF_ADDR, readl(ioaddr + DMA_CUR_TX_BUF_ADDR),
DMA_CUR_RX_BUF_ADDR, readl(ioaddr + DMA_CUR_RX_BUF_ADDR));
}
/* DMA controller has two counters to track the number of the missed frames. */
static void dwmac100_dma_diagnostic_fr(void *data, struct stmmac_extra_stats *x,
void __iomem *ioaddr)
{
struct net_device_stats *stats = (struct net_device_stats *)data;
u32 csr8 = readl(ioaddr + DMA_MISSED_FRAME_CTR);
if (unlikely(csr8)) {
if (csr8 & DMA_MISSED_FRAME_OVE) {
stats->rx_over_errors += 0x800;
x->rx_overflow_cntr += 0x800;
} else {
unsigned int ove_cntr;
ove_cntr = ((csr8 & DMA_MISSED_FRAME_OVE_CNTR) >> 17);
stats->rx_over_errors += ove_cntr;
x->rx_overflow_cntr += ove_cntr;
}
if (csr8 & DMA_MISSED_FRAME_OVE_M) {
stats->rx_missed_errors += 0xffff;
x->rx_missed_cntr += 0xffff;
} else {
unsigned int miss_f = (csr8 & DMA_MISSED_FRAME_M_CNTR);
stats->rx_missed_errors += miss_f;
x->rx_missed_cntr += miss_f;
}
}
}
const struct stmmac_dma_ops dwmac100_dma_ops = {
.reset = dwmac_dma_reset,
.init = dwmac100_dma_init,
.dump_regs = dwmac100_dump_dma_regs,
.dma_mode = dwmac100_dma_operation_mode,
.dma_diagnostic_fr = dwmac100_dma_diagnostic_fr,
.enable_dma_transmission = dwmac_enable_dma_transmission,
.enable_dma_irq = dwmac_enable_dma_irq,
.disable_dma_irq = dwmac_disable_dma_irq,
.start_tx = dwmac_dma_start_tx,
.stop_tx = dwmac_dma_stop_tx,
.start_rx = dwmac_dma_start_rx,
.stop_rx = dwmac_dma_stop_rx,
.dma_interrupt = dwmac_dma_interrupt,
};