- 根目录:
- drivers
- spi
- spi-ti-qspi.c
/*
* TI QSPI driver
*
* Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
* Author: Sourav Poddar <sourav.poddar@ti.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GPLv2.
*
* This program is distributed in the hope that 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/omap-dma.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/spi/spi.h>
struct ti_qspi_regs {
u32 clkctrl;
};
struct ti_qspi {
struct completion transfer_complete;
/* list synchronization */
struct mutex list_lock;
struct spi_master *master;
void __iomem *base;
void __iomem *ctrl_base;
void __iomem *mmap_base;
struct clk *fclk;
struct device *dev;
struct ti_qspi_regs ctx_reg;
u32 spi_max_frequency;
u32 cmd;
u32 dc;
bool ctrl_mod;
};
#define QSPI_PID (0x0)
#define QSPI_SYSCONFIG (0x10)
#define QSPI_INTR_STATUS_RAW_SET (0x20)
#define QSPI_INTR_STATUS_ENABLED_CLEAR (0x24)
#define QSPI_INTR_ENABLE_SET_REG (0x28)
#define QSPI_INTR_ENABLE_CLEAR_REG (0x2c)
#define QSPI_SPI_CLOCK_CNTRL_REG (0x40)
#define QSPI_SPI_DC_REG (0x44)
#define QSPI_SPI_CMD_REG (0x48)
#define QSPI_SPI_STATUS_REG (0x4c)
#define QSPI_SPI_DATA_REG (0x50)
#define QSPI_SPI_SETUP0_REG (0x54)
#define QSPI_SPI_SWITCH_REG (0x64)
#define QSPI_SPI_SETUP1_REG (0x58)
#define QSPI_SPI_SETUP2_REG (0x5c)
#define QSPI_SPI_SETUP3_REG (0x60)
#define QSPI_SPI_DATA_REG_1 (0x68)
#define QSPI_SPI_DATA_REG_2 (0x6c)
#define QSPI_SPI_DATA_REG_3 (0x70)
#define QSPI_COMPLETION_TIMEOUT msecs_to_jiffies(2000)
#define QSPI_FCLK 192000000
/* Clock Control */
#define QSPI_CLK_EN (1 << 31)
#define QSPI_CLK_DIV_MAX 0xffff
/* Command */
#define QSPI_EN_CS(n) (n << 28)
#define QSPI_WLEN(n) ((n - 1) << 19)
#define QSPI_3_PIN (1 << 18)
#define QSPI_RD_SNGL (1 << 16)
#define QSPI_WR_SNGL (2 << 16)
#define QSPI_RD_DUAL (3 << 16)
#define QSPI_RD_QUAD (7 << 16)
#define QSPI_INVAL (4 << 16)
#define QSPI_WC_CMD_INT_EN (1 << 14)
#define QSPI_FLEN(n) ((n - 1) << 0)
/* STATUS REGISTER */
#define WC 0x02
/* INTERRUPT REGISTER */
#define QSPI_WC_INT_EN (1 << 1)
#define QSPI_WC_INT_DISABLE (1 << 1)
/* Device Control */
#define QSPI_DD(m, n) (m << (3 + n * 8))
#define QSPI_CKPHA(n) (1 << (2 + n * 8))
#define QSPI_CSPOL(n) (1 << (1 + n * 8))
#define QSPI_CKPOL(n) (1 << (n * 8))
#define QSPI_FRAME 4096
#define QSPI_AUTOSUSPEND_TIMEOUT 2000
static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
unsigned long reg)
{
return readl(qspi->base + reg);
}
static inline void ti_qspi_write(struct ti_qspi *qspi,
unsigned long val, unsigned long reg)
{
writel(val, qspi->base + reg);
}
static int ti_qspi_setup(struct spi_device *spi)
{
struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
int clk_div = 0, ret;
u32 clk_ctrl_reg, clk_rate, clk_mask;
if (spi->master->busy) {
dev_dbg(qspi->dev, "master busy doing other trasnfers\n");
return -EBUSY;
}
if (!qspi->spi_max_frequency) {
dev_err(qspi->dev, "spi max frequency not defined\n");
return -EINVAL;
}
clk_rate = clk_get_rate(qspi->fclk);
clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
if (clk_div < 0) {
dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
return -EINVAL;
}
if (clk_div > QSPI_CLK_DIV_MAX) {
dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
return -EINVAL;
}
dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
qspi->spi_max_frequency, clk_div);
ret = pm_runtime_get_sync(qspi->dev);
if (ret < 0) {
dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
return ret;
}
clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
clk_ctrl_reg &= ~QSPI_CLK_EN;
/* disable SCLK */
ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
/* enable SCLK */
clk_mask = QSPI_CLK_EN | clk_div;
ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
ctx_reg->clkctrl = clk_mask;
pm_runtime_mark_last_busy(qspi->dev);
ret = pm_runtime_put_autosuspend(qspi->dev);
if (ret < 0) {
dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
return ret;
}
return 0;
}
static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
{
struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
}
static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
{
int wlen, count, ret;
unsigned int cmd;
const u8 *txbuf;
txbuf = t->tx_buf;
cmd = qspi->cmd | QSPI_WR_SNGL;
count = t->len;
wlen = t->bits_per_word >> 3; /* in bytes */
while (count) {
switch (wlen) {
case 1:
dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
cmd, qspi->dc, *txbuf);
writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
break;
case 2:
dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
cmd, qspi->dc, *txbuf);
writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
break;
case 4:
dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
cmd, qspi->dc, *txbuf);
writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
break;
}
ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
ret = wait_for_completion_timeout(&qspi->transfer_complete,
QSPI_COMPLETION_TIMEOUT);
if (ret == 0) {
dev_err(qspi->dev, "write timed out\n");
return -ETIMEDOUT;
}
txbuf += wlen;
count -= wlen;
}
return 0;
}
static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t)
{
int wlen, count, ret;
unsigned int cmd;
u8 *rxbuf;
rxbuf = t->rx_buf;
cmd = qspi->cmd;
switch (t->rx_nbits) {
case SPI_NBITS_DUAL:
cmd |= QSPI_RD_DUAL;
break;
case SPI_NBITS_QUAD:
cmd |= QSPI_RD_QUAD;
break;
default:
cmd |= QSPI_RD_SNGL;
break;
}
count = t->len;
wlen = t->bits_per_word >> 3; /* in bytes */
while (count) {
dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
ret = wait_for_completion_timeout(&qspi->transfer_complete,
QSPI_COMPLETION_TIMEOUT);
if (ret == 0) {
dev_err(qspi->dev, "read timed out\n");
return -ETIMEDOUT;
}
switch (wlen) {
case 1:
*rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG);
break;
case 2:
*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
break;
case 4:
*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
break;
}
rxbuf += wlen;
count -= wlen;
}
return 0;
}
static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t)
{
int ret;
if (t->tx_buf) {
ret = qspi_write_msg(qspi, t);
if (ret) {
dev_dbg(qspi->dev, "Error while writing\n");
return ret;
}
}
if (t->rx_buf) {
ret = qspi_read_msg(qspi, t);
if (ret) {
dev_dbg(qspi->dev, "Error while reading\n");
return ret;
}
}
return 0;
}
static int ti_qspi_start_transfer_one(struct spi_master *master,
struct spi_message *m)
{
struct ti_qspi *qspi = spi_master_get_devdata(master);
struct spi_device *spi = m->spi;
struct spi_transfer *t;
int status = 0, ret;
int frame_length;
/* setup device control reg */
qspi->dc = 0;
if (spi->mode & SPI_CPHA)
qspi->dc |= QSPI_CKPHA(spi->chip_select);
if (spi->mode & SPI_CPOL)
qspi->dc |= QSPI_CKPOL(spi->chip_select);
if (spi->mode & SPI_CS_HIGH)
qspi->dc |= QSPI_CSPOL(spi->chip_select);
frame_length = (m->frame_length << 3) / spi->bits_per_word;
frame_length = clamp(frame_length, 0, QSPI_FRAME);
/* setup command reg */
qspi->cmd = 0;
qspi->cmd |= QSPI_EN_CS(spi->chip_select);
qspi->cmd |= QSPI_FLEN(frame_length);
qspi->cmd |= QSPI_WC_CMD_INT_EN;
ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
mutex_lock(&qspi->list_lock);
list_for_each_entry(t, &m->transfers, transfer_list) {
qspi->cmd |= QSPI_WLEN(t->bits_per_word);
ret = qspi_transfer_msg(qspi, t);
if (ret) {
dev_dbg(qspi->dev, "transfer message failed\n");
mutex_unlock(&qspi->list_lock);
return -EINVAL;
}
m->actual_length += t->len;
}
mutex_unlock(&qspi->list_lock);
m->status = status;
spi_finalize_current_message(master);
ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
return status;
}
static irqreturn_t ti_qspi_isr(int irq, void *dev_id)
{
struct ti_qspi *qspi = dev_id;
u16 int_stat;
u32 stat;
irqreturn_t ret = IRQ_HANDLED;
int_stat = ti_qspi_read(qspi, QSPI_INTR_STATUS_ENABLED_CLEAR);
stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
if (!int_stat) {
dev_dbg(qspi->dev, "No IRQ triggered\n");
ret = IRQ_NONE;
goto out;
}
ti_qspi_write(qspi, QSPI_WC_INT_DISABLE,
QSPI_INTR_STATUS_ENABLED_CLEAR);
if (stat & WC)
complete(&qspi->transfer_complete);
out:
return ret;
}
static int ti_qspi_runtime_resume(struct device *dev)
{
struct ti_qspi *qspi;
qspi = dev_get_drvdata(dev);
ti_qspi_restore_ctx(qspi);
return 0;
}
static const struct of_device_id ti_qspi_match[] = {
{.compatible = "ti,dra7xxx-qspi" },
{.compatible = "ti,am4372-qspi" },
{},
};
MODULE_DEVICE_TABLE(of, ti_qspi_match);
static int ti_qspi_probe(struct platform_device *pdev)
{
struct ti_qspi *qspi;
struct spi_master *master;
struct resource *r, *res_ctrl, *res_mmap;
struct device_node *np = pdev->dev.of_node;
u32 max_freq;
int ret = 0, num_cs, irq;
master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
if (!master)
return -ENOMEM;
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
master->bus_num = -1;
master->flags = SPI_MASTER_HALF_DUPLEX;
master->setup = ti_qspi_setup;
master->auto_runtime_pm = true;
master->transfer_one_message = ti_qspi_start_transfer_one;
master->dev.of_node = pdev->dev.of_node;
master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
if (!of_property_read_u32(np, "num-cs", &num_cs))
master->num_chipselect = num_cs;
qspi = spi_master_get_devdata(master);
qspi->master = master;
qspi->dev = &pdev->dev;
platform_set_drvdata(pdev, qspi);
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
if (r == NULL) {
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (r == NULL) {
dev_err(&pdev->dev, "missing platform data\n");
return -ENODEV;
}
}
res_mmap = platform_get_resource_byname(pdev,
IORESOURCE_MEM, "qspi_mmap");
if (res_mmap == NULL) {
res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (res_mmap == NULL) {
dev_err(&pdev->dev,
"memory mapped resource not required\n");
return -ENODEV;
}
}
res_ctrl = platform_get_resource_byname(pdev,
IORESOURCE_MEM, "qspi_ctrlmod");
if (res_ctrl == NULL) {
res_ctrl = platform_get_resource(pdev, IORESOURCE_MEM, 2);
if (res_ctrl == NULL) {
dev_dbg(&pdev->dev,
"control module resources not required\n");
}
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "no irq resource?\n");
return irq;
}
mutex_init(&qspi->list_lock);
qspi->base = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(qspi->base)) {
ret = PTR_ERR(qspi->base);
goto free_master;
}
if (res_ctrl) {
qspi->ctrl_mod = true;
qspi->ctrl_base = devm_ioremap_resource(&pdev->dev, res_ctrl);
if (IS_ERR(qspi->ctrl_base)) {
ret = PTR_ERR(qspi->ctrl_base);
goto free_master;
}
}
if (res_mmap) {
qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap);
if (IS_ERR(qspi->mmap_base)) {
ret = PTR_ERR(qspi->mmap_base);
goto free_master;
}
}
ret = devm_request_irq(&pdev->dev, irq, ti_qspi_isr, 0,
dev_name(&pdev->dev), qspi);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
irq);
goto free_master;
}
qspi->fclk = devm_clk_get(&pdev->dev, "fck");
if (IS_ERR(qspi->fclk)) {
ret = PTR_ERR(qspi->fclk);
dev_err(&pdev->dev, "could not get clk: %d\n", ret);
}
init_completion(&qspi->transfer_complete);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
pm_runtime_enable(&pdev->dev);
if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
qspi->spi_max_frequency = max_freq;
ret = devm_spi_register_master(&pdev->dev, master);
if (ret)
goto free_master;
return 0;
free_master:
spi_master_put(master);
return ret;
}
static int ti_qspi_remove(struct platform_device *pdev)
{
struct ti_qspi *qspi = platform_get_drvdata(pdev);
int ret;
ret = pm_runtime_get_sync(qspi->dev);
if (ret < 0) {
dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
return ret;
}
ti_qspi_write(qspi, QSPI_WC_INT_DISABLE, QSPI_INTR_ENABLE_CLEAR_REG);
pm_runtime_put(qspi->dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
static const struct dev_pm_ops ti_qspi_pm_ops = {
.runtime_resume = ti_qspi_runtime_resume,
};
static struct platform_driver ti_qspi_driver = {
.probe = ti_qspi_probe,
.remove = ti_qspi_remove,
.driver = {
.name = "ti-qspi",
.owner = THIS_MODULE,
.pm = &ti_qspi_pm_ops,
.of_match_table = ti_qspi_match,
}
};
module_platform_driver(ti_qspi_driver);
MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TI QSPI controller driver");
MODULE_ALIAS("platform:ti-qspi");