OpenCloudOS-Kernel/drivers/mmc/host/mxcmmc.c

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/*
* linux/drivers/mmc/host/mxcmmc.c - Freescale i.MX MMCI driver
*
* This is a driver for the SDHC controller found in Freescale MX2/MX3
* SoCs. It is basically the same hardware as found on MX1 (imxmmc.c).
* Unlike the hardware found on MX1, this hardware just works and does
* not need all the quirks found in imxmmc.c, hence the separate driver.
*
* Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
* Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
*
* derived from pxamci.c by Russell King
*
* This program 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/module.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/blkdev.h>
#include <linux/dma-mapping.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/dmaengine.h>
#include <linux/types.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/of_gpio.h>
#include <linux/mmc/slot-gpio.h>
#include <asm/dma.h>
#include <asm/irq.h>
#include <linux/platform_data/mmc-mxcmmc.h>
#include <linux/platform_data/dma-imx.h>
#define DRIVER_NAME "mxc-mmc"
#define MXCMCI_TIMEOUT_MS 10000
#define MMC_REG_STR_STP_CLK 0x00
#define MMC_REG_STATUS 0x04
#define MMC_REG_CLK_RATE 0x08
#define MMC_REG_CMD_DAT_CONT 0x0C
#define MMC_REG_RES_TO 0x10
#define MMC_REG_READ_TO 0x14
#define MMC_REG_BLK_LEN 0x18
#define MMC_REG_NOB 0x1C
#define MMC_REG_REV_NO 0x20
#define MMC_REG_INT_CNTR 0x24
#define MMC_REG_CMD 0x28
#define MMC_REG_ARG 0x2C
#define MMC_REG_RES_FIFO 0x34
#define MMC_REG_BUFFER_ACCESS 0x38
#define STR_STP_CLK_RESET (1 << 3)
#define STR_STP_CLK_START_CLK (1 << 1)
#define STR_STP_CLK_STOP_CLK (1 << 0)
#define STATUS_CARD_INSERTION (1 << 31)
#define STATUS_CARD_REMOVAL (1 << 30)
#define STATUS_YBUF_EMPTY (1 << 29)
#define STATUS_XBUF_EMPTY (1 << 28)
#define STATUS_YBUF_FULL (1 << 27)
#define STATUS_XBUF_FULL (1 << 26)
#define STATUS_BUF_UND_RUN (1 << 25)
#define STATUS_BUF_OVFL (1 << 24)
#define STATUS_SDIO_INT_ACTIVE (1 << 14)
#define STATUS_END_CMD_RESP (1 << 13)
#define STATUS_WRITE_OP_DONE (1 << 12)
#define STATUS_DATA_TRANS_DONE (1 << 11)
#define STATUS_READ_OP_DONE (1 << 11)
#define STATUS_WR_CRC_ERROR_CODE_MASK (3 << 10)
#define STATUS_CARD_BUS_CLK_RUN (1 << 8)
#define STATUS_BUF_READ_RDY (1 << 7)
#define STATUS_BUF_WRITE_RDY (1 << 6)
#define STATUS_RESP_CRC_ERR (1 << 5)
#define STATUS_CRC_READ_ERR (1 << 3)
#define STATUS_CRC_WRITE_ERR (1 << 2)
#define STATUS_TIME_OUT_RESP (1 << 1)
#define STATUS_TIME_OUT_READ (1 << 0)
#define STATUS_ERR_MASK 0x2f
#define CMD_DAT_CONT_CMD_RESP_LONG_OFF (1 << 12)
#define CMD_DAT_CONT_STOP_READWAIT (1 << 11)
#define CMD_DAT_CONT_START_READWAIT (1 << 10)
#define CMD_DAT_CONT_BUS_WIDTH_4 (2 << 8)
#define CMD_DAT_CONT_INIT (1 << 7)
#define CMD_DAT_CONT_WRITE (1 << 4)
#define CMD_DAT_CONT_DATA_ENABLE (1 << 3)
#define CMD_DAT_CONT_RESPONSE_48BIT_CRC (1 << 0)
#define CMD_DAT_CONT_RESPONSE_136BIT (2 << 0)
#define CMD_DAT_CONT_RESPONSE_48BIT (3 << 0)
#define INT_SDIO_INT_WKP_EN (1 << 18)
#define INT_CARD_INSERTION_WKP_EN (1 << 17)
#define INT_CARD_REMOVAL_WKP_EN (1 << 16)
#define INT_CARD_INSERTION_EN (1 << 15)
#define INT_CARD_REMOVAL_EN (1 << 14)
#define INT_SDIO_IRQ_EN (1 << 13)
#define INT_DAT0_EN (1 << 12)
#define INT_BUF_READ_EN (1 << 4)
#define INT_BUF_WRITE_EN (1 << 3)
#define INT_END_CMD_RES_EN (1 << 2)
#define INT_WRITE_OP_DONE_EN (1 << 1)
#define INT_READ_OP_EN (1 << 0)
enum mxcmci_type {
IMX21_MMC,
IMX31_MMC,
MPC512X_MMC,
};
struct mxcmci_host {
struct mmc_host *mmc;
void __iomem *base;
dma_addr_t phys_base;
int detect_irq;
struct dma_chan *dma;
struct dma_async_tx_descriptor *desc;
int do_dma;
int default_irq_mask;
int use_sdio;
unsigned int power_mode;
struct imxmmc_platform_data *pdata;
struct mmc_request *req;
struct mmc_command *cmd;
struct mmc_data *data;
unsigned int datasize;
unsigned int dma_dir;
u16 rev_no;
unsigned int cmdat;
struct clk *clk_ipg;
struct clk *clk_per;
int clock;
struct work_struct datawork;
spinlock_t lock;
int burstlen;
int dmareq;
struct dma_slave_config dma_slave_config;
struct imx_dma_data dma_data;
struct timer_list watchdog;
enum mxcmci_type devtype;
};
static const struct platform_device_id mxcmci_devtype[] = {
{
.name = "imx21-mmc",
.driver_data = IMX21_MMC,
}, {
.name = "imx31-mmc",
.driver_data = IMX31_MMC,
}, {
.name = "mpc512x-sdhc",
.driver_data = MPC512X_MMC,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
static const struct of_device_id mxcmci_of_match[] = {
{
.compatible = "fsl,imx21-mmc",
.data = &mxcmci_devtype[IMX21_MMC],
}, {
.compatible = "fsl,imx31-mmc",
.data = &mxcmci_devtype[IMX31_MMC],
}, {
.compatible = "fsl,mpc5121-sdhc",
.data = &mxcmci_devtype[MPC512X_MMC],
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(of, mxcmci_of_match);
static inline int is_imx31_mmc(struct mxcmci_host *host)
{
return host->devtype == IMX31_MMC;
}
static inline int is_mpc512x_mmc(struct mxcmci_host *host)
{
return host->devtype == MPC512X_MMC;
}
static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
{
if (IS_ENABLED(CONFIG_PPC_MPC512x))
return ioread32be(host->base + reg);
else
return readl(host->base + reg);
}
static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
{
if (IS_ENABLED(CONFIG_PPC_MPC512x))
iowrite32be(val, host->base + reg);
else
writel(val, host->base + reg);
}
static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
{
if (IS_ENABLED(CONFIG_PPC_MPC512x))
return ioread32be(host->base + reg);
else
return readw(host->base + reg);
}
static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
{
if (IS_ENABLED(CONFIG_PPC_MPC512x))
iowrite32be(val, host->base + reg);
else
writew(val, host->base + reg);
}
static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
{
if (!IS_ERR(host->mmc->supply.vmmc)) {
if (host->power_mode == MMC_POWER_UP)
mmc_regulator_set_ocr(host->mmc,
host->mmc->supply.vmmc, vdd);
else if (host->power_mode == MMC_POWER_OFF)
mmc_regulator_set_ocr(host->mmc,
host->mmc->supply.vmmc, 0);
}
if (host->pdata && host->pdata->setpower)
host->pdata->setpower(mmc_dev(host->mmc), vdd);
}
static inline int mxcmci_use_dma(struct mxcmci_host *host)
{
return host->do_dma;
}
static void mxcmci_softreset(struct mxcmci_host *host)
{
int i;
dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
/* reset sequence */
mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
MMC_REG_STR_STP_CLK);
for (i = 0; i < 8; i++)
mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
}
#if IS_ENABLED(CONFIG_PPC_MPC512x)
static inline void buffer_swap32(u32 *buf, int len)
{
int i;
for (i = 0; i < ((len + 3) / 4); i++) {
*buf = swab32(*buf);
buf++;
}
}
static void mxcmci_swap_buffers(struct mmc_data *data)
{
struct scatterlist *sg;
int i;
for_each_sg(data->sg, sg, data->sg_len, i)
buffer_swap32(sg_virt(sg), sg->length);
}
#else
static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
#endif
static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
{
unsigned int nob = data->blocks;
unsigned int blksz = data->blksz;
unsigned int datasize = nob * blksz;
struct scatterlist *sg;
enum dma_transfer_direction slave_dirn;
int i, nents;
host->data = data;
data->bytes_xfered = 0;
mxcmci_writew(host, nob, MMC_REG_NOB);
mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
host->datasize = datasize;
if (!mxcmci_use_dma(host))
return 0;
for_each_sg(data->sg, sg, data->sg_len, i) {
if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
host->do_dma = 0;
return 0;
}
}
if (data->flags & MMC_DATA_READ) {
host->dma_dir = DMA_FROM_DEVICE;
slave_dirn = DMA_DEV_TO_MEM;
} else {
host->dma_dir = DMA_TO_DEVICE;
slave_dirn = DMA_MEM_TO_DEV;
mxcmci_swap_buffers(data);
}
nents = dma_map_sg(host->dma->device->dev, data->sg,
data->sg_len, host->dma_dir);
if (nents != data->sg_len)
return -EINVAL;
host->desc = dmaengine_prep_slave_sg(host->dma,
data->sg, data->sg_len, slave_dirn,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!host->desc) {
dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
host->dma_dir);
host->do_dma = 0;
return 0; /* Fall back to PIO */
}
wmb();
dmaengine_submit(host->desc);
dma_async_issue_pending(host->dma);
mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
return 0;
}
static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
static void mxcmci_dma_callback(void *data)
{
struct mxcmci_host *host = data;
u32 stat;
del_timer(&host->watchdog);
stat = mxcmci_readl(host, MMC_REG_STATUS);
dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
mxcmci_data_done(host, stat);
}
static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
unsigned int cmdat)
{
u32 int_cntr = host->default_irq_mask;
unsigned long flags;
WARN_ON(host->cmd != NULL);
host->cmd = cmd;
switch (mmc_resp_type(cmd)) {
case MMC_RSP_R1: /* short CRC, OPCODE */
case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
break;
case MMC_RSP_R2: /* long 136 bit + CRC */
cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
break;
case MMC_RSP_R3: /* short */
cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
break;
case MMC_RSP_NONE:
break;
default:
dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
mmc_resp_type(cmd));
cmd->error = -EINVAL;
return -EINVAL;
}
int_cntr = INT_END_CMD_RES_EN;
if (mxcmci_use_dma(host)) {
if (host->dma_dir == DMA_FROM_DEVICE) {
host->desc->callback = mxcmci_dma_callback;
host->desc->callback_param = host;
} else {
int_cntr |= INT_WRITE_OP_DONE_EN;
}
}
spin_lock_irqsave(&host->lock, flags);
if (host->use_sdio)
int_cntr |= INT_SDIO_IRQ_EN;
mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
spin_unlock_irqrestore(&host->lock, flags);
mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
return 0;
}
static void mxcmci_finish_request(struct mxcmci_host *host,
struct mmc_request *req)
{
u32 int_cntr = host->default_irq_mask;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
if (host->use_sdio)
int_cntr |= INT_SDIO_IRQ_EN;
mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
spin_unlock_irqrestore(&host->lock, flags);
host->req = NULL;
host->cmd = NULL;
host->data = NULL;
mmc_request_done(host->mmc, req);
}
static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
{
struct mmc_data *data = host->data;
int data_error;
if (mxcmci_use_dma(host)) {
dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
host->dma_dir);
mxcmci_swap_buffers(data);
}
if (stat & STATUS_ERR_MASK) {
dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
stat);
if (stat & STATUS_CRC_READ_ERR) {
dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
data->error = -EILSEQ;
} else if (stat & STATUS_CRC_WRITE_ERR) {
u32 err_code = (stat >> 9) & 0x3;
if (err_code == 2) { /* No CRC response */
dev_err(mmc_dev(host->mmc),
"%s: No CRC -ETIMEDOUT\n", __func__);
data->error = -ETIMEDOUT;
} else {
dev_err(mmc_dev(host->mmc),
"%s: -EILSEQ\n", __func__);
data->error = -EILSEQ;
}
} else if (stat & STATUS_TIME_OUT_READ) {
dev_err(mmc_dev(host->mmc),
"%s: read -ETIMEDOUT\n", __func__);
data->error = -ETIMEDOUT;
} else {
dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
data->error = -EIO;
}
} else {
data->bytes_xfered = host->datasize;
}
data_error = data->error;
host->data = NULL;
return data_error;
}
static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
{
struct mmc_command *cmd = host->cmd;
int i;
u32 a, b, c;
if (!cmd)
return;
if (stat & STATUS_TIME_OUT_RESP) {
dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
cmd->error = -ETIMEDOUT;
} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
cmd->error = -EILSEQ;
}
if (cmd->flags & MMC_RSP_PRESENT) {
if (cmd->flags & MMC_RSP_136) {
for (i = 0; i < 4; i++) {
a = mxcmci_readw(host, MMC_REG_RES_FIFO);
b = mxcmci_readw(host, MMC_REG_RES_FIFO);
cmd->resp[i] = a << 16 | b;
}
} else {
a = mxcmci_readw(host, MMC_REG_RES_FIFO);
b = mxcmci_readw(host, MMC_REG_RES_FIFO);
c = mxcmci_readw(host, MMC_REG_RES_FIFO);
cmd->resp[0] = a << 24 | b << 8 | c >> 8;
}
}
}
static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
{
u32 stat;
unsigned long timeout = jiffies + HZ;
do {
stat = mxcmci_readl(host, MMC_REG_STATUS);
if (stat & STATUS_ERR_MASK)
return stat;
if (time_after(jiffies, timeout)) {
mxcmci_softreset(host);
mxcmci_set_clk_rate(host, host->clock);
return STATUS_TIME_OUT_READ;
}
if (stat & mask)
return 0;
cpu_relax();
} while (1);
}
static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
{
unsigned int stat;
u32 *buf = _buf;
while (bytes > 3) {
stat = mxcmci_poll_status(host,
STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
if (stat)
return stat;
*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
bytes -= 4;
}
if (bytes) {
u8 *b = (u8 *)buf;
u32 tmp;
stat = mxcmci_poll_status(host,
STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
if (stat)
return stat;
tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
memcpy(b, &tmp, bytes);
}
return 0;
}
static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
{
unsigned int stat;
u32 *buf = _buf;
while (bytes > 3) {
stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
if (stat)
return stat;
mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
bytes -= 4;
}
if (bytes) {
u8 *b = (u8 *)buf;
u32 tmp;
stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
if (stat)
return stat;
memcpy(&tmp, b, bytes);
mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
}
return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
}
static int mxcmci_transfer_data(struct mxcmci_host *host)
{
struct mmc_data *data = host->req->data;
struct scatterlist *sg;
int stat, i;
host->data = data;
host->datasize = 0;
if (data->flags & MMC_DATA_READ) {
for_each_sg(data->sg, sg, data->sg_len, i) {
stat = mxcmci_pull(host, sg_virt(sg), sg->length);
if (stat)
return stat;
host->datasize += sg->length;
}
} else {
for_each_sg(data->sg, sg, data->sg_len, i) {
stat = mxcmci_push(host, sg_virt(sg), sg->length);
if (stat)
return stat;
host->datasize += sg->length;
}
stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
if (stat)
return stat;
}
return 0;
}
static void mxcmci_datawork(struct work_struct *work)
{
struct mxcmci_host *host = container_of(work, struct mxcmci_host,
datawork);
int datastat = mxcmci_transfer_data(host);
mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
MMC_REG_STATUS);
mxcmci_finish_data(host, datastat);
if (host->req->stop) {
if (mxcmci_start_cmd(host, host->req->stop, 0)) {
mxcmci_finish_request(host, host->req);
return;
}
} else {
mxcmci_finish_request(host, host->req);
}
}
static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
{
struct mmc_request *req;
int data_error;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
if (!host->data) {
spin_unlock_irqrestore(&host->lock, flags);
return;
}
if (!host->req) {
spin_unlock_irqrestore(&host->lock, flags);
return;
}
req = host->req;
if (!req->stop)
host->req = NULL; /* we will handle finish req below */
data_error = mxcmci_finish_data(host, stat);
spin_unlock_irqrestore(&host->lock, flags);
mxcmci_read_response(host, stat);
host->cmd = NULL;
if (req->stop) {
if (mxcmci_start_cmd(host, req->stop, 0)) {
mxcmci_finish_request(host, req);
return;
}
} else {
mxcmci_finish_request(host, req);
}
}
static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
{
mxcmci_read_response(host, stat);
host->cmd = NULL;
if (!host->data && host->req) {
mxcmci_finish_request(host, host->req);
return;
}
/* For the DMA case the DMA engine handles the data transfer
* automatically. For non DMA we have to do it ourselves.
* Don't do it in interrupt context though.
*/
if (!mxcmci_use_dma(host) && host->data)
schedule_work(&host->datawork);
}
static irqreturn_t mxcmci_irq(int irq, void *devid)
{
struct mxcmci_host *host = devid;
unsigned long flags;
bool sdio_irq;
u32 stat;
stat = mxcmci_readl(host, MMC_REG_STATUS);
mxcmci_writel(host,
stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
STATUS_WRITE_OP_DONE),
MMC_REG_STATUS);
dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
spin_lock_irqsave(&host->lock, flags);
sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
spin_unlock_irqrestore(&host->lock, flags);
mmc: mxcmmc: fix race condition when dma finish a data transfer During a read of data block using dma, driver might have two ways to finish to read and free the resources: 1) checking STATUS_DATA_TRANS_DONE mask, in the mxcmci_irq() routine (pending to mmc irq) 2) mxmmc driver, registers also a mxcmci_dma_callback() and when transfer is finished, dma driver calls this callback. (pending to dma irq) Both ways are concurrent with each other. Race condition happens when following events occur: /* (1) mxcmci driver start data transfer */ 158.418970: mpc_dma_execute: mpc_dma_execute(): will_access_peripheral start cid=31 158.418976: mpc_dma_issue_pending <-mxcmci_request 158.418983: mxcmci_start_cmd <-mxcmci_request /* (2) mxcmci driver receive mmc irq */ 158.419656: mxcmci_irq <-handle_irq_event_percpu 158.419692: mxcmci_read_response <-mxcmci_irq /* (3) mxcmci driver checks that transfer is complete and call mxcmci_finish_data() */ 158.419726: mxcmci_data_done <-mxcmci_irq 158.419729: mxcmci_finish_data <-mxcmci_data_done 158.419733: dma_direct_unmap_sg <-mxcmci_finish_data 158.419736: mxcmci_swap_buffers.isra.24 <-mxcmci_finish_data 158.419762: mxcmci_read_response <-mxcmci_data_done /* (4) mxcmci driver (no dma): send stop command */ 158.419765: mxcmci_start_cmd <-mxcmci_data_done /* (5) mxcmci driver (no dma): receive the stop command irq response */ 158.419782: mxcmci_irq <-handle_irq_event_percpu 158.419812: mxcmci_read_response <-mxcmci_irq 158.419843: mxcmci_finish_request <-mxcmci_irq /* (6) dma driver: receive dma irq (finish data transfer) related by request on step 1 */ 158.419853: mpc_dma_irq <-handle_irq_event_percpu 158.420001: mpc_dma_irq_process <-mpc_dma_irq 158.420004: mpc_dma_irq_process <-mpc_dma_irq /* (7) dma driver: start dma tasklet to finish the dma irq handling */ 158.420008: mpc_dma_irq_process: mpc_dma_irq_process(): completed ch:31 /* (8) mxcmci driver: start next data transfer using dma */ 158.420174: mxcmci_request <-mmc_start_req 158.420182: dma_direct_map_sg <-mxcmci_request 158.420192: mpc_dma_prep_slave_sg <-mxcmci_request /* (9) dma driver: schedule irq tasklet and execute mxcmci dma driver callback */ 158.420250: mpc_dma_tasklet <-tasklet_action 158.420254: mpc_dma_process_completed <-tasklet_action 158.420267: mxcmci_dma_callback <-mpc_dma_process_completed /* ERROR!!! (10) mxcmci driver callback works on dma data related to the step 1 that is already finished */ 158.420271: mxcmci_data_done <-mpc_dma_process_completed 158.420273: mxcmci_finish_data <-mxcmci_data_done /* ERROR!!! (11) mxcmci driver: clear data that should be used by step 8 and send an other mmc stop command (already sended on step 4) */ 158.420276: dma_direct_unmap_sg <-mxcmci_finish_data 158.420279: mxcmci_swap_buffers.isra.24 <-mxcmci_finish_data 158.420330: mxcmci_read_response <-mxcmci_data_done 158.420333: mxcmci_start_cmd <-mxcmci_data_done 158.420338: dma_run_dependencies <-mpc_dma_process_completed ... ... ... 168.474223: mxcmci_watchdog <-call_timer_fn 168.474236: mxcmci_watchdog: mxcmci_watchdog 168.474397: mpc_dma_device_control <-mxcmci_watchdog In accordance with the other drivers that using the dma engine, fix it, leaving *only* to dma driver the complete control to ending the read operation. Removing STATUS_READ_OP_DONE event activation, has as effect to force mxcmci driver to handle the finish data transfer only by mxcmci dma callback. Signed-off-by: Matteo Facchinetti <matteo.facchinetti@sirius-es.it> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-09-30 22:59:37 +08:00
if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
if (sdio_irq) {
mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
mmc_signal_sdio_irq(host->mmc);
}
if (stat & STATUS_END_CMD_RESP)
mxcmci_cmd_done(host, stat);
mmc: mxcmmc: fix race condition when dma finish a data transfer During a read of data block using dma, driver might have two ways to finish to read and free the resources: 1) checking STATUS_DATA_TRANS_DONE mask, in the mxcmci_irq() routine (pending to mmc irq) 2) mxmmc driver, registers also a mxcmci_dma_callback() and when transfer is finished, dma driver calls this callback. (pending to dma irq) Both ways are concurrent with each other. Race condition happens when following events occur: /* (1) mxcmci driver start data transfer */ 158.418970: mpc_dma_execute: mpc_dma_execute(): will_access_peripheral start cid=31 158.418976: mpc_dma_issue_pending <-mxcmci_request 158.418983: mxcmci_start_cmd <-mxcmci_request /* (2) mxcmci driver receive mmc irq */ 158.419656: mxcmci_irq <-handle_irq_event_percpu 158.419692: mxcmci_read_response <-mxcmci_irq /* (3) mxcmci driver checks that transfer is complete and call mxcmci_finish_data() */ 158.419726: mxcmci_data_done <-mxcmci_irq 158.419729: mxcmci_finish_data <-mxcmci_data_done 158.419733: dma_direct_unmap_sg <-mxcmci_finish_data 158.419736: mxcmci_swap_buffers.isra.24 <-mxcmci_finish_data 158.419762: mxcmci_read_response <-mxcmci_data_done /* (4) mxcmci driver (no dma): send stop command */ 158.419765: mxcmci_start_cmd <-mxcmci_data_done /* (5) mxcmci driver (no dma): receive the stop command irq response */ 158.419782: mxcmci_irq <-handle_irq_event_percpu 158.419812: mxcmci_read_response <-mxcmci_irq 158.419843: mxcmci_finish_request <-mxcmci_irq /* (6) dma driver: receive dma irq (finish data transfer) related by request on step 1 */ 158.419853: mpc_dma_irq <-handle_irq_event_percpu 158.420001: mpc_dma_irq_process <-mpc_dma_irq 158.420004: mpc_dma_irq_process <-mpc_dma_irq /* (7) dma driver: start dma tasklet to finish the dma irq handling */ 158.420008: mpc_dma_irq_process: mpc_dma_irq_process(): completed ch:31 /* (8) mxcmci driver: start next data transfer using dma */ 158.420174: mxcmci_request <-mmc_start_req 158.420182: dma_direct_map_sg <-mxcmci_request 158.420192: mpc_dma_prep_slave_sg <-mxcmci_request /* (9) dma driver: schedule irq tasklet and execute mxcmci dma driver callback */ 158.420250: mpc_dma_tasklet <-tasklet_action 158.420254: mpc_dma_process_completed <-tasklet_action 158.420267: mxcmci_dma_callback <-mpc_dma_process_completed /* ERROR!!! (10) mxcmci driver callback works on dma data related to the step 1 that is already finished */ 158.420271: mxcmci_data_done <-mpc_dma_process_completed 158.420273: mxcmci_finish_data <-mxcmci_data_done /* ERROR!!! (11) mxcmci driver: clear data that should be used by step 8 and send an other mmc stop command (already sended on step 4) */ 158.420276: dma_direct_unmap_sg <-mxcmci_finish_data 158.420279: mxcmci_swap_buffers.isra.24 <-mxcmci_finish_data 158.420330: mxcmci_read_response <-mxcmci_data_done 158.420333: mxcmci_start_cmd <-mxcmci_data_done 158.420338: dma_run_dependencies <-mpc_dma_process_completed ... ... ... 168.474223: mxcmci_watchdog <-call_timer_fn 168.474236: mxcmci_watchdog: mxcmci_watchdog 168.474397: mpc_dma_device_control <-mxcmci_watchdog In accordance with the other drivers that using the dma engine, fix it, leaving *only* to dma driver the complete control to ending the read operation. Removing STATUS_READ_OP_DONE event activation, has as effect to force mxcmci driver to handle the finish data transfer only by mxcmci dma callback. Signed-off-by: Matteo Facchinetti <matteo.facchinetti@sirius-es.it> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-09-30 22:59:37 +08:00
if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
del_timer(&host->watchdog);
mxcmci_data_done(host, stat);
}
if (host->default_irq_mask &&
(stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
mmc_detect_change(host->mmc, msecs_to_jiffies(200));
return IRQ_HANDLED;
}
static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
{
struct mxcmci_host *host = mmc_priv(mmc);
unsigned int cmdat = host->cmdat;
int error;
WARN_ON(host->req != NULL);
host->req = req;
host->cmdat &= ~CMD_DAT_CONT_INIT;
if (host->dma)
host->do_dma = 1;
if (req->data) {
error = mxcmci_setup_data(host, req->data);
if (error) {
req->cmd->error = error;
goto out;
}
cmdat |= CMD_DAT_CONT_DATA_ENABLE;
if (req->data->flags & MMC_DATA_WRITE)
cmdat |= CMD_DAT_CONT_WRITE;
}
error = mxcmci_start_cmd(host, req->cmd, cmdat);
out:
if (error)
mxcmci_finish_request(host, req);
}
static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
{
unsigned int divider;
int prescaler = 0;
unsigned int clk_in = clk_get_rate(host->clk_per);
while (prescaler <= 0x800) {
for (divider = 1; divider <= 0xF; divider++) {
int x;
x = (clk_in / (divider + 1));
if (prescaler)
x /= (prescaler * 2);
if (x <= clk_ios)
break;
}
if (divider < 0x10)
break;
if (prescaler == 0)
prescaler = 1;
else
prescaler <<= 1;
}
mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
prescaler, divider, clk_in, clk_ios);
}
static int mxcmci_setup_dma(struct mmc_host *mmc)
{
struct mxcmci_host *host = mmc_priv(mmc);
struct dma_slave_config *config = &host->dma_slave_config;
config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
config->dst_addr_width = 4;
config->src_addr_width = 4;
config->dst_maxburst = host->burstlen;
config->src_maxburst = host->burstlen;
config->device_fc = false;
return dmaengine_slave_config(host->dma, config);
}
static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct mxcmci_host *host = mmc_priv(mmc);
int burstlen, ret;
/*
* use burstlen of 64 (16 words) in 4 bit mode (--> reg value 0)
* use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
*/
if (ios->bus_width == MMC_BUS_WIDTH_4)
burstlen = 16;
else
burstlen = 4;
if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
host->burstlen = burstlen;
ret = mxcmci_setup_dma(mmc);
if (ret) {
dev_err(mmc_dev(host->mmc),
"failed to config DMA channel. Falling back to PIO\n");
dma_release_channel(host->dma);
host->do_dma = 0;
host->dma = NULL;
}
}
if (ios->bus_width == MMC_BUS_WIDTH_4)
host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
else
host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
if (host->power_mode != ios->power_mode) {
host->power_mode = ios->power_mode;
mxcmci_set_power(host, ios->vdd);
if (ios->power_mode == MMC_POWER_ON)
host->cmdat |= CMD_DAT_CONT_INIT;
}
if (ios->clock) {
mxcmci_set_clk_rate(host, ios->clock);
mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
} else {
mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
}
host->clock = ios->clock;
}
static irqreturn_t mxcmci_detect_irq(int irq, void *data)
{
struct mmc_host *mmc = data;
dev_dbg(mmc_dev(mmc), "%s\n", __func__);
mmc_detect_change(mmc, msecs_to_jiffies(250));
return IRQ_HANDLED;
}
static int mxcmci_get_ro(struct mmc_host *mmc)
{
struct mxcmci_host *host = mmc_priv(mmc);
if (host->pdata && host->pdata->get_ro)
return !!host->pdata->get_ro(mmc_dev(mmc));
/*
* If board doesn't support read only detection (no mmc_gpio
* context or gpio is invalid), then let the mmc core decide
* what to do.
*/
return mmc_gpio_get_ro(mmc);
}
static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
{
struct mxcmci_host *host = mmc_priv(mmc);
unsigned long flags;
u32 int_cntr;
spin_lock_irqsave(&host->lock, flags);
host->use_sdio = enable;
int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
if (enable)
int_cntr |= INT_SDIO_IRQ_EN;
else
int_cntr &= ~INT_SDIO_IRQ_EN;
mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
spin_unlock_irqrestore(&host->lock, flags);
}
static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
{
struct mxcmci_host *mxcmci = mmc_priv(host);
/*
* MX3 SoCs have a silicon bug which corrupts CRC calculation of
* multi-block transfers when connected SDIO peripheral doesn't
* drive the BUSY line as required by the specs.
* One way to prevent this is to only allow 1-bit transfers.
*/
if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
host->caps &= ~MMC_CAP_4_BIT_DATA;
else
host->caps |= MMC_CAP_4_BIT_DATA;
}
static bool filter(struct dma_chan *chan, void *param)
{
struct mxcmci_host *host = param;
if (!imx_dma_is_general_purpose(chan))
return false;
chan->private = &host->dma_data;
return true;
}
static void mxcmci_watchdog(unsigned long data)
{
struct mmc_host *mmc = (struct mmc_host *)data;
struct mxcmci_host *host = mmc_priv(mmc);
struct mmc_request *req = host->req;
unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
if (host->dma_dir == DMA_FROM_DEVICE) {
dmaengine_terminate_all(host->dma);
dev_err(mmc_dev(host->mmc),
"%s: read time out (status = 0x%08x)\n",
__func__, stat);
} else {
dev_err(mmc_dev(host->mmc),
"%s: write time out (status = 0x%08x)\n",
__func__, stat);
mxcmci_softreset(host);
}
/* Mark transfer as erroneus and inform the upper layers */
if (host->data)
host->data->error = -ETIMEDOUT;
host->req = NULL;
host->cmd = NULL;
host->data = NULL;
mmc_request_done(host->mmc, req);
}
static const struct mmc_host_ops mxcmci_ops = {
.request = mxcmci_request,
.set_ios = mxcmci_set_ios,
.get_ro = mxcmci_get_ro,
.enable_sdio_irq = mxcmci_enable_sdio_irq,
.init_card = mxcmci_init_card,
};
static int mxcmci_probe(struct platform_device *pdev)
{
struct mmc_host *mmc;
struct mxcmci_host *host;
struct resource *res;
int ret = 0, irq;
bool dat3_card_detect = false;
dma_cap_mask_t mask;
const struct of_device_id *of_id;
struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
pr_info("i.MX/MPC512x SDHC driver\n");
of_id = of_match_device(mxcmci_of_match, &pdev->dev);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -EINVAL;
mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
if (!mmc)
return -ENOMEM;
host = mmc_priv(mmc);
host->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(host->base)) {
ret = PTR_ERR(host->base);
goto out_free;
}
host->phys_base = res->start;
ret = mmc_of_parse(mmc);
if (ret)
goto out_free;
mmc->ops = &mxcmci_ops;
/* For devicetree parsing, the bus width is read from devicetree */
if (pdata)
mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
else
mmc->caps |= MMC_CAP_SDIO_IRQ;
/* MMC core transfer sizes tunable parameters */
mmc->max_blk_size = 2048;
mmc->max_blk_count = 65535;
mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
mmc->max_seg_size = mmc->max_req_size;
if (of_id) {
const struct platform_device_id *id_entry = of_id->data;
host->devtype = id_entry->driver_data;
} else {
host->devtype = pdev->id_entry->driver_data;
}
/* adjust max_segs after devtype detection */
if (!is_mpc512x_mmc(host))
mmc->max_segs = 64;
host->mmc = mmc;
host->pdata = pdata;
spin_lock_init(&host->lock);
if (pdata)
dat3_card_detect = pdata->dat3_card_detect;
else if (!(mmc->caps & MMC_CAP_NONREMOVABLE)
&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
dat3_card_detect = true;
ret = mmc_regulator_get_supply(mmc);
if (ret == -EPROBE_DEFER)
goto out_free;
if (!mmc->ocr_avail) {
if (pdata && pdata->ocr_avail)
mmc->ocr_avail = pdata->ocr_avail;
else
mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
}
if (dat3_card_detect)
host->default_irq_mask =
INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
else
host->default_irq_mask = 0;
host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(host->clk_ipg)) {
ret = PTR_ERR(host->clk_ipg);
goto out_free;
}
host->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(host->clk_per)) {
ret = PTR_ERR(host->clk_per);
goto out_free;
}
clk_prepare_enable(host->clk_per);
clk_prepare_enable(host->clk_ipg);
mxcmci_softreset(host);
host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
if (host->rev_no != 0x400) {
ret = -ENODEV;
dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
host->rev_no);
goto out_clk_put;
}
mmc->f_min = clk_get_rate(host->clk_per) >> 16;
mmc->f_max = clk_get_rate(host->clk_per) >> 1;
/* recommended in data sheet */
mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
if (!host->pdata) {
host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
} else {
res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (res) {
host->dmareq = res->start;
host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
host->dma_data.priority = DMA_PRIO_LOW;
host->dma_data.dma_request = host->dmareq;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
host->dma = dma_request_channel(mask, filter, host);
}
}
if (host->dma)
mmc->max_seg_size = dma_get_max_seg_size(
host->dma->device->dev);
else
dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
INIT_WORK(&host->datawork, mxcmci_datawork);
ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
dev_name(&pdev->dev), host);
if (ret)
goto out_free_dma;
platform_set_drvdata(pdev, mmc);
if (host->pdata && host->pdata->init) {
ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
host->mmc);
if (ret)
goto out_free_dma;
}
init_timer(&host->watchdog);
host->watchdog.function = &mxcmci_watchdog;
host->watchdog.data = (unsigned long)mmc;
mmc_add_host(mmc);
return 0;
out_free_dma:
if (host->dma)
dma_release_channel(host->dma);
out_clk_put:
clk_disable_unprepare(host->clk_per);
clk_disable_unprepare(host->clk_ipg);
out_free:
mmc_free_host(mmc);
return ret;
}
static int mxcmci_remove(struct platform_device *pdev)
{
struct mmc_host *mmc = platform_get_drvdata(pdev);
struct mxcmci_host *host = mmc_priv(mmc);
mmc_remove_host(mmc);
if (host->pdata && host->pdata->exit)
host->pdata->exit(&pdev->dev, mmc);
if (host->dma)
dma_release_channel(host->dma);
clk_disable_unprepare(host->clk_per);
clk_disable_unprepare(host->clk_ipg);
mmc_free_host(mmc);
return 0;
}
static int __maybe_unused mxcmci_suspend(struct device *dev)
{
struct mmc_host *mmc = dev_get_drvdata(dev);
struct mxcmci_host *host = mmc_priv(mmc);
clk_disable_unprepare(host->clk_per);
clk_disable_unprepare(host->clk_ipg);
return 0;
}
static int __maybe_unused mxcmci_resume(struct device *dev)
{
struct mmc_host *mmc = dev_get_drvdata(dev);
struct mxcmci_host *host = mmc_priv(mmc);
clk_prepare_enable(host->clk_per);
clk_prepare_enable(host->clk_ipg);
return 0;
}
static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
static struct platform_driver mxcmci_driver = {
.probe = mxcmci_probe,
.remove = mxcmci_remove,
.id_table = mxcmci_devtype,
.driver = {
.name = DRIVER_NAME,
.pm = &mxcmci_pm_ops,
.of_match_table = mxcmci_of_match,
}
};
module_platform_driver(mxcmci_driver);
MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
MODULE_AUTHOR("Sascha Hauer, Pengutronix");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mxc-mmc");