linux_dsm_epyc7002/drivers/mtd/devices/st_spi_fsm.c

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/*
* st_spi_fsm.c - ST Fast Sequence Mode (FSM) Serial Flash Controller
*
* Author: Angus Clark <angus.clark@st.com>
*
* Copyright (C) 2010-2014 STicroelectronics Limited
*
* JEDEC probe based on drivers/mtd/devices/m25p80.c
*
* This code is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mtd/mtd.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/of.h>
#include "serial_flash_cmds.h"
/*
* FSM SPI Controller Registers
*/
#define SPI_CLOCKDIV 0x0010
#define SPI_MODESELECT 0x0018
#define SPI_CONFIGDATA 0x0020
#define SPI_STA_MODE_CHANGE 0x0028
#define SPI_FAST_SEQ_TRANSFER_SIZE 0x0100
#define SPI_FAST_SEQ_ADD1 0x0104
#define SPI_FAST_SEQ_ADD2 0x0108
#define SPI_FAST_SEQ_ADD_CFG 0x010c
#define SPI_FAST_SEQ_OPC1 0x0110
#define SPI_FAST_SEQ_OPC2 0x0114
#define SPI_FAST_SEQ_OPC3 0x0118
#define SPI_FAST_SEQ_OPC4 0x011c
#define SPI_FAST_SEQ_OPC5 0x0120
#define SPI_MODE_BITS 0x0124
#define SPI_DUMMY_BITS 0x0128
#define SPI_FAST_SEQ_FLASH_STA_DATA 0x012c
#define SPI_FAST_SEQ_1 0x0130
#define SPI_FAST_SEQ_2 0x0134
#define SPI_FAST_SEQ_3 0x0138
#define SPI_FAST_SEQ_4 0x013c
#define SPI_FAST_SEQ_CFG 0x0140
#define SPI_FAST_SEQ_STA 0x0144
#define SPI_QUAD_BOOT_SEQ_INIT_1 0x0148
#define SPI_QUAD_BOOT_SEQ_INIT_2 0x014c
#define SPI_QUAD_BOOT_READ_SEQ_1 0x0150
#define SPI_QUAD_BOOT_READ_SEQ_2 0x0154
#define SPI_PROGRAM_ERASE_TIME 0x0158
#define SPI_MULT_PAGE_REPEAT_SEQ_1 0x015c
#define SPI_MULT_PAGE_REPEAT_SEQ_2 0x0160
#define SPI_STATUS_WR_TIME_REG 0x0164
#define SPI_FAST_SEQ_DATA_REG 0x0300
/*
* Register: SPI_MODESELECT
*/
#define SPI_MODESELECT_CONTIG 0x01
#define SPI_MODESELECT_FASTREAD 0x02
#define SPI_MODESELECT_DUALIO 0x04
#define SPI_MODESELECT_FSM 0x08
#define SPI_MODESELECT_QUADBOOT 0x10
/*
* Register: SPI_CONFIGDATA
*/
#define SPI_CFG_DEVICE_ST 0x1
#define SPI_CFG_DEVICE_ATMEL 0x4
#define SPI_CFG_MIN_CS_HIGH(x) (((x) & 0xfff) << 4)
#define SPI_CFG_CS_SETUPHOLD(x) (((x) & 0xff) << 16)
#define SPI_CFG_DATA_HOLD(x) (((x) & 0xff) << 24)
#define SPI_CFG_DEFAULT_MIN_CS_HIGH SPI_CFG_MIN_CS_HIGH(0x0AA)
#define SPI_CFG_DEFAULT_CS_SETUPHOLD SPI_CFG_CS_SETUPHOLD(0xA0)
#define SPI_CFG_DEFAULT_DATA_HOLD SPI_CFG_DATA_HOLD(0x00)
/*
* Register: SPI_FAST_SEQ_TRANSFER_SIZE
*/
#define TRANSFER_SIZE(x) ((x) * 8)
/*
* Register: SPI_FAST_SEQ_ADD_CFG
*/
#define ADR_CFG_CYCLES_ADD1(x) ((x) << 0)
#define ADR_CFG_PADS_1_ADD1 (0x0 << 6)
#define ADR_CFG_PADS_2_ADD1 (0x1 << 6)
#define ADR_CFG_PADS_4_ADD1 (0x3 << 6)
#define ADR_CFG_CSDEASSERT_ADD1 (1 << 8)
#define ADR_CFG_CYCLES_ADD2(x) ((x) << (0+16))
#define ADR_CFG_PADS_1_ADD2 (0x0 << (6+16))
#define ADR_CFG_PADS_2_ADD2 (0x1 << (6+16))
#define ADR_CFG_PADS_4_ADD2 (0x3 << (6+16))
#define ADR_CFG_CSDEASSERT_ADD2 (1 << (8+16))
/*
* Register: SPI_FAST_SEQ_n
*/
#define SEQ_OPC_OPCODE(x) ((x) << 0)
#define SEQ_OPC_CYCLES(x) ((x) << 8)
#define SEQ_OPC_PADS_1 (0x0 << 14)
#define SEQ_OPC_PADS_2 (0x1 << 14)
#define SEQ_OPC_PADS_4 (0x3 << 14)
#define SEQ_OPC_CSDEASSERT (1 << 16)
/*
* Register: SPI_FAST_SEQ_CFG
*/
#define SEQ_CFG_STARTSEQ (1 << 0)
#define SEQ_CFG_SWRESET (1 << 5)
#define SEQ_CFG_CSDEASSERT (1 << 6)
#define SEQ_CFG_READNOTWRITE (1 << 7)
#define SEQ_CFG_ERASE (1 << 8)
#define SEQ_CFG_PADS_1 (0x0 << 16)
#define SEQ_CFG_PADS_2 (0x1 << 16)
#define SEQ_CFG_PADS_4 (0x3 << 16)
/*
* Register: SPI_MODE_BITS
*/
#define MODE_DATA(x) (x & 0xff)
#define MODE_CYCLES(x) ((x & 0x3f) << 16)
#define MODE_PADS_1 (0x0 << 22)
#define MODE_PADS_2 (0x1 << 22)
#define MODE_PADS_4 (0x3 << 22)
#define DUMMY_CSDEASSERT (1 << 24)
/*
* Register: SPI_DUMMY_BITS
*/
#define DUMMY_CYCLES(x) ((x & 0x3f) << 16)
#define DUMMY_PADS_1 (0x0 << 22)
#define DUMMY_PADS_2 (0x1 << 22)
#define DUMMY_PADS_4 (0x3 << 22)
#define DUMMY_CSDEASSERT (1 << 24)
/*
* Register: SPI_FAST_SEQ_FLASH_STA_DATA
*/
#define STA_DATA_BYTE1(x) ((x & 0xff) << 0)
#define STA_DATA_BYTE2(x) ((x & 0xff) << 8)
#define STA_PADS_1 (0x0 << 16)
#define STA_PADS_2 (0x1 << 16)
#define STA_PADS_4 (0x3 << 16)
#define STA_CSDEASSERT (0x1 << 20)
#define STA_RDNOTWR (0x1 << 21)
/*
* FSM SPI Instruction Opcodes
*/
#define STFSM_OPC_CMD 0x1
#define STFSM_OPC_ADD 0x2
#define STFSM_OPC_STA 0x3
#define STFSM_OPC_MODE 0x4
#define STFSM_OPC_DUMMY 0x5
#define STFSM_OPC_DATA 0x6
#define STFSM_OPC_WAIT 0x7
#define STFSM_OPC_JUMP 0x8
#define STFSM_OPC_GOTO 0x9
#define STFSM_OPC_STOP 0xF
/*
* FSM SPI Instructions (== opcode + operand).
*/
#define STFSM_INSTR(cmd, op) ((cmd) | ((op) << 4))
#define STFSM_INST_CMD1 STFSM_INSTR(STFSM_OPC_CMD, 1)
#define STFSM_INST_CMD2 STFSM_INSTR(STFSM_OPC_CMD, 2)
#define STFSM_INST_CMD3 STFSM_INSTR(STFSM_OPC_CMD, 3)
#define STFSM_INST_CMD4 STFSM_INSTR(STFSM_OPC_CMD, 4)
#define STFSM_INST_CMD5 STFSM_INSTR(STFSM_OPC_CMD, 5)
#define STFSM_INST_ADD1 STFSM_INSTR(STFSM_OPC_ADD, 1)
#define STFSM_INST_ADD2 STFSM_INSTR(STFSM_OPC_ADD, 2)
#define STFSM_INST_DATA_WRITE STFSM_INSTR(STFSM_OPC_DATA, 1)
#define STFSM_INST_DATA_READ STFSM_INSTR(STFSM_OPC_DATA, 2)
#define STFSM_INST_STA_RD1 STFSM_INSTR(STFSM_OPC_STA, 0x1)
#define STFSM_INST_STA_WR1 STFSM_INSTR(STFSM_OPC_STA, 0x1)
#define STFSM_INST_STA_RD2 STFSM_INSTR(STFSM_OPC_STA, 0x2)
#define STFSM_INST_STA_WR1_2 STFSM_INSTR(STFSM_OPC_STA, 0x3)
#define STFSM_INST_MODE STFSM_INSTR(STFSM_OPC_MODE, 0)
#define STFSM_INST_DUMMY STFSM_INSTR(STFSM_OPC_DUMMY, 0)
#define STFSM_INST_WAIT STFSM_INSTR(STFSM_OPC_WAIT, 0)
#define STFSM_INST_STOP STFSM_INSTR(STFSM_OPC_STOP, 0)
#define STFSM_DEFAULT_EMI_FREQ 100000000UL /* 100 MHz */
#define STFSM_DEFAULT_WR_TIME (STFSM_DEFAULT_EMI_FREQ * (15/1000)) /* 15ms */
#define STFSM_FLASH_SAFE_FREQ 10000000UL /* 10 MHz */
#define STFSM_MAX_WAIT_SEQ_MS 1000 /* FSM execution time */
struct stfsm {
struct device *dev;
void __iomem *base;
struct resource *region;
struct mtd_info mtd;
struct mutex lock;
uint32_t fifo_dir_delay;
};
struct stfsm_seq {
uint32_t data_size;
uint32_t addr1;
uint32_t addr2;
uint32_t addr_cfg;
uint32_t seq_opc[5];
uint32_t mode;
uint32_t dummy;
uint32_t status;
uint8_t seq[16];
uint32_t seq_cfg;
} __packed __aligned(4);
static struct stfsm_seq stfsm_seq_read_jedec = {
.data_size = TRANSFER_SIZE(8),
.seq_opc[0] = (SEQ_OPC_PADS_1 |
SEQ_OPC_CYCLES(8) |
SEQ_OPC_OPCODE(FLASH_CMD_RDID)),
.seq = {
STFSM_INST_CMD1,
STFSM_INST_DATA_READ,
STFSM_INST_STOP,
},
.seq_cfg = (SEQ_CFG_PADS_1 |
SEQ_CFG_READNOTWRITE |
SEQ_CFG_CSDEASSERT |
SEQ_CFG_STARTSEQ),
};
static inline int stfsm_is_idle(struct stfsm *fsm)
{
return readl(fsm->base + SPI_FAST_SEQ_STA) & 0x10;
}
static inline uint32_t stfsm_fifo_available(struct stfsm *fsm)
{
return (readl(fsm->base + SPI_FAST_SEQ_STA) >> 5) & 0x7f;
}
static void stfsm_clear_fifo(struct stfsm *fsm)
{
uint32_t avail;
for (;;) {
avail = stfsm_fifo_available(fsm);
if (!avail)
break;
while (avail) {
readl(fsm->base + SPI_FAST_SEQ_DATA_REG);
avail--;
}
}
}
static inline void stfsm_load_seq(struct stfsm *fsm,
const struct stfsm_seq *seq)
{
void __iomem *dst = fsm->base + SPI_FAST_SEQ_TRANSFER_SIZE;
const uint32_t *src = (const uint32_t *)seq;
int words = sizeof(*seq) / sizeof(*src);
BUG_ON(!stfsm_is_idle(fsm));
while (words--) {
writel(*src, dst);
src++;
dst += 4;
}
}
static void stfsm_wait_seq(struct stfsm *fsm)
{
unsigned long deadline;
int timeout = 0;
deadline = jiffies + msecs_to_jiffies(STFSM_MAX_WAIT_SEQ_MS);
while (!timeout) {
if (time_after_eq(jiffies, deadline))
timeout = 1;
if (stfsm_is_idle(fsm))
return;
cond_resched();
}
dev_err(fsm->dev, "timeout on sequence completion\n");
}
static void stfsm_read_fifo(struct stfsm *fsm, uint32_t *buf,
const uint32_t size)
{
uint32_t remaining = size >> 2;
uint32_t avail;
uint32_t words;
dev_dbg(fsm->dev, "Reading %d bytes from FIFO\n", size);
BUG_ON((((uint32_t)buf) & 0x3) || (size & 0x3));
while (remaining) {
for (;;) {
avail = stfsm_fifo_available(fsm);
if (avail)
break;
udelay(1);
}
words = min(avail, remaining);
remaining -= words;
readsl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
buf += words;
}
}
static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *const jedec)
{
const struct stfsm_seq *seq = &stfsm_seq_read_jedec;
uint32_t tmp[2];
stfsm_load_seq(fsm, seq);
stfsm_read_fifo(fsm, tmp, 8);
memcpy(jedec, tmp, 5);
stfsm_wait_seq(fsm);
}
static struct flash_info *stfsm_jedec_probe(struct stfsm *fsm)
{
u16 ext_jedec;
u32 jedec;
u8 id[5];
stfsm_read_jedec(fsm, id);
jedec = id[0] << 16 | id[1] << 8 | id[2];
/*
* JEDEC also defines an optional "extended device information"
* string for after vendor-specific data, after the three bytes
* we use here. Supporting some chips might require using it.
*/
ext_jedec = id[3] << 8 | id[4];
dev_dbg(fsm->dev, "JEDEC = 0x%08x [%02x %02x %02x %02x %02x]\n",
jedec, id[0], id[1], id[2], id[3], id[4]);
return NULL;
}
static int stfsm_set_mode(struct stfsm *fsm, uint32_t mode)
{
int ret, timeout = 10;
/* Wait for controller to accept mode change */
while (--timeout) {
ret = readl(fsm->base + SPI_STA_MODE_CHANGE);
if (ret & 0x1)
break;
udelay(1);
}
if (!timeout)
return -EBUSY;
writel(mode, fsm->base + SPI_MODESELECT);
return 0;
}
static void stfsm_set_freq(struct stfsm *fsm, uint32_t spi_freq)
{
uint32_t emi_freq;
uint32_t clk_div;
/* TODO: Make this dynamic */
emi_freq = STFSM_DEFAULT_EMI_FREQ;
/*
* Calculate clk_div - values between 2 and 128
* Multiple of 2, rounded up
*/
clk_div = 2 * DIV_ROUND_UP(emi_freq, 2 * spi_freq);
if (clk_div < 2)
clk_div = 2;
else if (clk_div > 128)
clk_div = 128;
/*
* Determine a suitable delay for the IP to complete a change of
* direction of the FIFO. The required delay is related to the clock
* divider used. The following heuristics are based on empirical tests,
* using a 100MHz EMI clock.
*/
if (clk_div <= 4)
fsm->fifo_dir_delay = 0;
else if (clk_div <= 10)
fsm->fifo_dir_delay = 1;
else
fsm->fifo_dir_delay = DIV_ROUND_UP(clk_div, 10);
dev_dbg(fsm->dev, "emi_clk = %uHZ, spi_freq = %uHZ, clk_div = %u\n",
emi_freq, spi_freq, clk_div);
writel(clk_div, fsm->base + SPI_CLOCKDIV);
}
static int stfsm_init(struct stfsm *fsm)
{
int ret;
/* Perform a soft reset of the FSM controller */
writel(SEQ_CFG_SWRESET, fsm->base + SPI_FAST_SEQ_CFG);
udelay(1);
writel(0, fsm->base + SPI_FAST_SEQ_CFG);
/* Set clock to 'safe' frequency initially */
stfsm_set_freq(fsm, STFSM_FLASH_SAFE_FREQ);
/* Switch to FSM */
ret = stfsm_set_mode(fsm, SPI_MODESELECT_FSM);
if (ret)
return ret;
/* Set timing parameters */
writel(SPI_CFG_DEVICE_ST |
SPI_CFG_DEFAULT_MIN_CS_HIGH |
SPI_CFG_DEFAULT_CS_SETUPHOLD |
SPI_CFG_DEFAULT_DATA_HOLD,
fsm->base + SPI_CONFIGDATA);
writel(STFSM_DEFAULT_WR_TIME, fsm->base + SPI_STATUS_WR_TIME_REG);
/* Clear FIFO, just in case */
stfsm_clear_fifo(fsm);
return 0;
}
static int stfsm_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct resource *res;
struct stfsm *fsm;
int ret;
if (!np) {
dev_err(&pdev->dev, "No DT found\n");
return -EINVAL;
}
fsm = devm_kzalloc(&pdev->dev, sizeof(*fsm), GFP_KERNEL);
if (!fsm)
return -ENOMEM;
fsm->dev = &pdev->dev;
platform_set_drvdata(pdev, fsm);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "Resource not found\n");
return -ENODEV;
}
fsm->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(fsm->base)) {
dev_err(&pdev->dev,
"Failed to reserve memory region %pR\n", res);
return PTR_ERR(fsm->base);
}
mutex_init(&fsm->lock);
ret = stfsm_init(fsm);
if (ret) {
dev_err(&pdev->dev, "Failed to initialise FSM Controller\n");
return ret;
}
/* Detect SPI FLASH device */
stfsm_jedec_probe(fsm);
fsm->mtd.dev.parent = &pdev->dev;
fsm->mtd.type = MTD_NORFLASH;
fsm->mtd.writesize = 4;
fsm->mtd.writebufsize = fsm->mtd.writesize;
fsm->mtd.flags = MTD_CAP_NORFLASH;
return mtd_device_parse_register(&fsm->mtd, NULL, NULL, NULL, 0);
}
static int stfsm_remove(struct platform_device *pdev)
{
struct stfsm *fsm = platform_get_drvdata(pdev);
int err;
err = mtd_device_unregister(&fsm->mtd);
if (err)
return err;
return 0;
}
static struct of_device_id stfsm_match[] = {
{ .compatible = "st,spi-fsm", },
{},
};
MODULE_DEVICE_TABLE(of, stfsm_match);
static struct platform_driver stfsm_driver = {
.probe = stfsm_probe,
.remove = stfsm_remove,
.driver = {
.name = "st-spi-fsm",
.owner = THIS_MODULE,
.of_match_table = stfsm_match,
},
};
module_platform_driver(stfsm_driver);
MODULE_AUTHOR("Angus Clark <angus.clark@st.com>");
MODULE_DESCRIPTION("ST SPI FSM driver");
MODULE_LICENSE("GPL");