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// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/drivers/mmc/host/pxa.c - PXA MMCI driver
*
* Copyright (C) 2003 Russell King, All Rights Reserved.
*
* This hardware is really sick:
* - No way to clear interrupts.
* - Have to turn off the clock whenever we touch the device.
* - Doesn't tell you how many data blocks were transferred.
* Yuck!
*
* 1 and 3 byte data transfers not supported
* max block length up to 1023
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/mmc/host.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/io.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio/consumer.h>
#include <linux/gfp.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/sizes.h>
#include <mach/hardware.h>
#include <linux/platform_data/mmc-pxamci.h>
#include "pxamci.h"
#define DRIVER_NAME "pxa2xx-mci"
#define NR_SG 1
#define CLKRT_OFF (~0)
#define mmc_has_26MHz() (cpu_is_pxa300() || cpu_is_pxa310() \
|| cpu_is_pxa935())
struct pxamci_host {
struct mmc_host *mmc;
spinlock_t lock;
struct resource *res;
void __iomem *base;
struct clk *clk;
unsigned long clkrate;
unsigned int clkrt;
unsigned int cmdat;
unsigned int imask;
unsigned int power_mode;
unsigned long detect_delay_ms;
bool use_ro_gpio;
struct gpio_desc *power;
struct pxamci_platform_data *pdata;
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
struct dma_chan *dma_chan_rx;
struct dma_chan *dma_chan_tx;
dma_cookie_t dma_cookie;
unsigned int dma_len;
unsigned int dma_dir;
};
static int pxamci_init_ocr(struct pxamci_host *host)
{
struct mmc_host *mmc = host->mmc;
int ret;
ret = mmc_regulator_get_supply(mmc);
if (ret < 0)
return ret;
if (IS_ERR(mmc->supply.vmmc)) {
/* fall-back to platform data */
mmc->ocr_avail = host->pdata ?
host->pdata->ocr_mask :
MMC_VDD_32_33 | MMC_VDD_33_34;
}
return 0;
}
static inline int pxamci_set_power(struct pxamci_host *host,
unsigned char power_mode,
unsigned int vdd)
{
struct mmc_host *mmc = host->mmc;
struct regulator *supply = mmc->supply.vmmc;
if (!IS_ERR(supply))
return mmc_regulator_set_ocr(mmc, supply, vdd);
if (host->power) {
bool on = !!((1 << vdd) & host->pdata->ocr_mask);
gpiod_set_value(host->power, on);
}
if (host->pdata && host->pdata->setpower)
return host->pdata->setpower(mmc_dev(host->mmc), vdd);
return 0;
}
static void pxamci_stop_clock(struct pxamci_host *host)
{
if (readl(host->base + MMC_STAT) & STAT_CLK_EN) {
unsigned long timeout = 10000;
unsigned int v;
writel(STOP_CLOCK, host->base + MMC_STRPCL);
do {
v = readl(host->base + MMC_STAT);
if (!(v & STAT_CLK_EN))
break;
udelay(1);
} while (timeout--);
if (v & STAT_CLK_EN)
dev_err(mmc_dev(host->mmc), "unable to stop clock\n");
}
}
static void pxamci_enable_irq(struct pxamci_host *host, unsigned int mask)
{
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
host->imask &= ~mask;
writel(host->imask, host->base + MMC_I_MASK);
spin_unlock_irqrestore(&host->lock, flags);
}
static void pxamci_disable_irq(struct pxamci_host *host, unsigned int mask)
{
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
host->imask |= mask;
writel(host->imask, host->base + MMC_I_MASK);
spin_unlock_irqrestore(&host->lock, flags);
}
static void pxamci_dma_irq(void *param);
static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
{
struct dma_async_tx_descriptor *tx;
enum dma_transfer_direction direction;
struct dma_slave_config config;
struct dma_chan *chan;
unsigned int nob = data->blocks;
unsigned long long clks;
unsigned int timeout;
int ret;
host->data = data;
writel(nob, host->base + MMC_NOB);
writel(data->blksz, host->base + MMC_BLKLEN);
clks = (unsigned long long)data->timeout_ns * host->clkrate;
do_div(clks, 1000000000UL);
timeout = (unsigned int)clks + (data->timeout_clks << host->clkrt);
writel((timeout + 255) / 256, host->base + MMC_RDTO);
memset(&config, 0, sizeof(config));
config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
config.src_addr = host->res->start + MMC_RXFIFO;
config.dst_addr = host->res->start + MMC_TXFIFO;
config.src_maxburst = 32;
config.dst_maxburst = 32;
if (data->flags & MMC_DATA_READ) {
host->dma_dir = DMA_FROM_DEVICE;
direction = DMA_DEV_TO_MEM;
chan = host->dma_chan_rx;
} else {
host->dma_dir = DMA_TO_DEVICE;
direction = DMA_MEM_TO_DEV;
chan = host->dma_chan_tx;
}
config.direction = direction;
ret = dmaengine_slave_config(chan, &config);
if (ret < 0) {
dev_err(mmc_dev(host->mmc), "dma slave config failed\n");
return;
}
host->dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
host->dma_dir);
tx = dmaengine_prep_slave_sg(chan, data->sg, host->dma_len, direction,
DMA_PREP_INTERRUPT);
if (!tx) {
dev_err(mmc_dev(host->mmc), "prep_slave_sg() failed\n");
return;
}
if (!(data->flags & MMC_DATA_READ)) {
tx->callback = pxamci_dma_irq;
tx->callback_param = host;
}
host->dma_cookie = dmaengine_submit(tx);
/*
* workaround for erratum #91:
* only start DMA now if we are doing a read,
* otherwise we wait until CMD/RESP has finished
* before starting DMA.
*/
if (!cpu_is_pxa27x() || data->flags & MMC_DATA_READ)
dma_async_issue_pending(chan);
}
static void pxamci_start_cmd(struct pxamci_host *host, struct mmc_command *cmd, unsigned int cmdat)
{
WARN_ON(host->cmd != NULL);
host->cmd = cmd;
if (cmd->flags & MMC_RSP_BUSY)
cmdat |= CMDAT_BUSY;
#define RSP_TYPE(x) ((x) & ~(MMC_RSP_BUSY|MMC_RSP_OPCODE))
switch (RSP_TYPE(mmc_resp_type(cmd))) {
case RSP_TYPE(MMC_RSP_R1): /* r1, r1b, r6, r7 */
cmdat |= CMDAT_RESP_SHORT;
break;
case RSP_TYPE(MMC_RSP_R3):
cmdat |= CMDAT_RESP_R3;
break;
case RSP_TYPE(MMC_RSP_R2):
cmdat |= CMDAT_RESP_R2;
break;
default:
break;
}
writel(cmd->opcode, host->base + MMC_CMD);
writel(cmd->arg >> 16, host->base + MMC_ARGH);
writel(cmd->arg & 0xffff, host->base + MMC_ARGL);
writel(cmdat, host->base + MMC_CMDAT);
writel(host->clkrt, host->base + MMC_CLKRT);
writel(START_CLOCK, host->base + MMC_STRPCL);
pxamci_enable_irq(host, END_CMD_RES);
}
static void pxamci_finish_request(struct pxamci_host *host, struct mmc_request *mrq)
{
host->mrq = NULL;
host->cmd = NULL;
host->data = NULL;
mmc_request_done(host->mmc, mrq);
}
static int pxamci_cmd_done(struct pxamci_host *host, unsigned int stat)
{
struct mmc_command *cmd = host->cmd;
int i;
u32 v;
if (!cmd)
return 0;
host->cmd = NULL;
/*
* Did I mention this is Sick. We always need to
* discard the upper 8 bits of the first 16-bit word.
*/
v = readl(host->base + MMC_RES) & 0xffff;
for (i = 0; i < 4; i++) {
u32 w1 = readl(host->base + MMC_RES) & 0xffff;
u32 w2 = readl(host->base + MMC_RES) & 0xffff;
cmd->resp[i] = v << 24 | w1 << 8 | w2 >> 8;
v = w2;
}
if (stat & STAT_TIME_OUT_RESPONSE) {
cmd->error = -ETIMEDOUT;
} else if (stat & STAT_RES_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
/*
* workaround for erratum #42:
* Intel PXA27x Family Processor Specification Update Rev 001
* A bogus CRC error can appear if the msb of a 136 bit
* response is a one.
*/
if (cpu_is_pxa27x() &&
(cmd->flags & MMC_RSP_136 && cmd->resp[0] & 0x80000000))
pr_debug("ignoring CRC from command %d - *risky*\n", cmd->opcode);
else
cmd->error = -EILSEQ;
}
pxamci_disable_irq(host, END_CMD_RES);
if (host->data && !cmd->error) {
pxamci_enable_irq(host, DATA_TRAN_DONE);
/*
* workaround for erratum #91, if doing write
* enable DMA late
*/
if (cpu_is_pxa27x() && host->data->flags & MMC_DATA_WRITE)
dma_async_issue_pending(host->dma_chan_tx);
} else {
pxamci_finish_request(host, host->mrq);
}
return 1;
}
static int pxamci_data_done(struct pxamci_host *host, unsigned int stat)
{
struct mmc_data *data = host->data;
struct dma_chan *chan;
if (!data)
return 0;
if (data->flags & MMC_DATA_READ)
chan = host->dma_chan_rx;
else
chan = host->dma_chan_tx;
dma_unmap_sg(chan->device->dev,
data->sg, data->sg_len, host->dma_dir);
if (stat & STAT_READ_TIME_OUT)
data->error = -ETIMEDOUT;
else if (stat & (STAT_CRC_READ_ERROR|STAT_CRC_WRITE_ERROR))
data->error = -EILSEQ;
/*
* There appears to be a hardware design bug here. There seems to
* be no way to find out how much data was transferred to the card.
* This means that if there was an error on any block, we mark all
* data blocks as being in error.
*/
if (!data->error)
data->bytes_xfered = data->blocks * data->blksz;
else
data->bytes_xfered = 0;
pxamci_disable_irq(host, DATA_TRAN_DONE);
host->data = NULL;
if (host->mrq->stop) {
pxamci_stop_clock(host);
pxamci_start_cmd(host, host->mrq->stop, host->cmdat);
} else {
pxamci_finish_request(host, host->mrq);
}
return 1;
}
static irqreturn_t pxamci_irq(int irq, void *devid)
{
struct pxamci_host *host = devid;
unsigned int ireg;
int handled = 0;
ireg = readl(host->base + MMC_I_REG) & ~readl(host->base + MMC_I_MASK);
if (ireg) {
unsigned stat = readl(host->base + MMC_STAT);
pr_debug("PXAMCI: irq %08x stat %08x\n", ireg, stat);
if (ireg & END_CMD_RES)
handled |= pxamci_cmd_done(host, stat);
if (ireg & DATA_TRAN_DONE)
handled |= pxamci_data_done(host, stat);
if (ireg & SDIO_INT) {
mmc_signal_sdio_irq(host->mmc);
handled = 1;
}
}
return IRQ_RETVAL(handled);
}
static void pxamci_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct pxamci_host *host = mmc_priv(mmc);
unsigned int cmdat;
WARN_ON(host->mrq != NULL);
host->mrq = mrq;
pxamci_stop_clock(host);
cmdat = host->cmdat;
host->cmdat &= ~CMDAT_INIT;
if (mrq->data) {
pxamci_setup_data(host, mrq->data);
cmdat &= ~CMDAT_BUSY;
cmdat |= CMDAT_DATAEN | CMDAT_DMAEN;
if (mrq->data->flags & MMC_DATA_WRITE)
cmdat |= CMDAT_WRITE;
}
pxamci_start_cmd(host, mrq->cmd, cmdat);
}
static int pxamci_get_ro(struct mmc_host *mmc)
{
struct pxamci_host *host = mmc_priv(mmc);
if (host->use_ro_gpio)
return mmc_gpio_get_ro(mmc);
if (host->pdata && host->pdata->get_ro)
return !!host->pdata->get_ro(mmc_dev(mmc));
/*
* Board doesn't support read only detection; let the mmc core
* decide what to do.
*/
return -ENOSYS;
}
static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct pxamci_host *host = mmc_priv(mmc);
if (ios->clock) {
unsigned long rate = host->clkrate;
unsigned int clk = rate / ios->clock;
if (host->clkrt == CLKRT_OFF)
clk_prepare_enable(host->clk);
if (ios->clock == 26000000) {
/* to support 26MHz */
host->clkrt = 7;
} else {
/* to handle (19.5MHz, 26MHz) */
if (!clk)
clk = 1;
/*
* clk might result in a lower divisor than we
* desire. check for that condition and adjust
* as appropriate.
*/
if (rate / clk > ios->clock)
clk <<= 1;
host->clkrt = fls(clk) - 1;
}
/*
* we write clkrt on the next command
*/
} else {
pxamci_stop_clock(host);
if (host->clkrt != CLKRT_OFF) {
host->clkrt = CLKRT_OFF;
clk_disable_unprepare(host->clk);
}
}
if (host->power_mode != ios->power_mode) {
int ret;
host->power_mode = ios->power_mode;
ret = pxamci_set_power(host, ios->power_mode, ios->vdd);
if (ret) {
dev_err(mmc_dev(mmc), "unable to set power\n");
/*
* The .set_ios() function in the mmc_host_ops
* struct return void, and failing to set the
* power should be rare so we print an error and
* return here.
*/
return;
}
if (ios->power_mode == MMC_POWER_ON)
host->cmdat |= CMDAT_INIT;
}
if (ios->bus_width == MMC_BUS_WIDTH_4)
host->cmdat |= CMDAT_SD_4DAT;
else
host->cmdat &= ~CMDAT_SD_4DAT;
dev_dbg(mmc_dev(mmc), "PXAMCI: clkrt = %x cmdat = %x\n",
host->clkrt, host->cmdat);
}
static void pxamci_enable_sdio_irq(struct mmc_host *host, int enable)
{
struct pxamci_host *pxa_host = mmc_priv(host);
if (enable)
pxamci_enable_irq(pxa_host, SDIO_INT);
else
pxamci_disable_irq(pxa_host, SDIO_INT);
}
static const struct mmc_host_ops pxamci_ops = {
.request = pxamci_request,
.get_cd = mmc_gpio_get_cd,
.get_ro = pxamci_get_ro,
.set_ios = pxamci_set_ios,
.enable_sdio_irq = pxamci_enable_sdio_irq,
};
static void pxamci_dma_irq(void *param)
{
struct pxamci_host *host = param;
struct dma_tx_state state;
enum dma_status status;
struct dma_chan *chan;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
if (!host->data)
goto out_unlock;
if (host->data->flags & MMC_DATA_READ)
chan = host->dma_chan_rx;
else
chan = host->dma_chan_tx;
status = dmaengine_tx_status(chan, host->dma_cookie, &state);
if (likely(status == DMA_COMPLETE)) {
writel(BUF_PART_FULL, host->base + MMC_PRTBUF);
} else {
pr_err("%s: DMA error on %s channel\n", mmc_hostname(host->mmc),
host->data->flags & MMC_DATA_READ ? "rx" : "tx");
host->data->error = -EIO;
pxamci_data_done(host, 0);
}
out_unlock:
spin_unlock_irqrestore(&host->lock, flags);
}
static irqreturn_t pxamci_detect_irq(int irq, void *devid)
{
struct pxamci_host *host = mmc_priv(devid);
mmc_detect_change(devid, msecs_to_jiffies(host->detect_delay_ms));
return IRQ_HANDLED;
}
#ifdef CONFIG_OF
static const struct of_device_id pxa_mmc_dt_ids[] = {
{ .compatible = "marvell,pxa-mmc" },
{ }
};
MODULE_DEVICE_TABLE(of, pxa_mmc_dt_ids);
static int pxamci_of_init(struct platform_device *pdev,
struct mmc_host *mmc)
{
struct device_node *np = pdev->dev.of_node;
struct pxamci_host *host = mmc_priv(mmc);
u32 tmp;
int ret;
if (!np)
return 0;
/* pxa-mmc specific */
if (of_property_read_u32(np, "pxa-mmc,detect-delay-ms", &tmp) == 0)
host->detect_delay_ms = tmp;
ret = mmc_of_parse(mmc);
if (ret < 0)
return ret;
return 0;
}
#else
static int pxamci_of_init(struct platform_device *pdev,
struct mmc_host *mmc)
{
return 0;
}
#endif
static int pxamci_probe(struct platform_device *pdev)
{
struct mmc_host *mmc;
struct pxamci_host *host = NULL;
struct device *dev = &pdev->dev;
struct resource *r;
int ret, irq;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
mmc = mmc_alloc_host(sizeof(struct pxamci_host), dev);
if (!mmc) {
ret = -ENOMEM;
goto out;
}
mmc->ops = &pxamci_ops;
/*
* We can do SG-DMA, but we don't because we never know how much
* data we successfully wrote to the card.
*/
mmc->max_segs = NR_SG;
/*
* Our hardware DMA can handle a maximum of one page per SG entry.
*/
mmc->max_seg_size = PAGE_SIZE;
/*
* Block length register is only 10 bits before PXA27x.
*/
mmc->max_blk_size = cpu_is_pxa25x() ? 1023 : 2048;
/*
* Block count register is 16 bits.
*/
mmc->max_blk_count = 65535;
ret = pxamci_of_init(pdev, mmc);
if (ret)
return ret;
host = mmc_priv(mmc);
host->mmc = mmc;
host->pdata = pdev->dev.platform_data;
host->clkrt = CLKRT_OFF;
host->clk = devm_clk_get(dev, NULL);
if (IS_ERR(host->clk)) {
ret = PTR_ERR(host->clk);
host->clk = NULL;
goto out;
}
host->clkrate = clk_get_rate(host->clk);
/*
* Calculate minimum clock rate, rounding up.
*/
mmc->f_min = (host->clkrate + 63) / 64;
mmc->f_max = (mmc_has_26MHz()) ? 26000000 : host->clkrate;
ret = pxamci_init_ocr(host);
if (ret < 0)
return ret;
mmc->caps = 0;
host->cmdat = 0;
if (!cpu_is_pxa25x()) {
mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
host->cmdat |= CMDAT_SDIO_INT_EN;
if (mmc_has_26MHz())
mmc->caps |= MMC_CAP_MMC_HIGHSPEED |
MMC_CAP_SD_HIGHSPEED;
}
spin_lock_init(&host->lock);
host->res = r;
host->imask = MMC_I_MASK_ALL;
host->base = devm_ioremap_resource(dev, r);
if (IS_ERR(host->base)) {
ret = PTR_ERR(host->base);
goto out;
}
/*
* Ensure that the host controller is shut down, and setup
* with our defaults.
*/
pxamci_stop_clock(host);
writel(0, host->base + MMC_SPI);
writel(64, host->base + MMC_RESTO);
writel(host->imask, host->base + MMC_I_MASK);
ret = devm_request_irq(dev, irq, pxamci_irq, 0,
DRIVER_NAME, host);
if (ret)
goto out;
platform_set_drvdata(pdev, mmc);
host->dma_chan_rx = dma_request_slave_channel(dev, "rx");
if (host->dma_chan_rx == NULL) {
dev_err(dev, "unable to request rx dma channel\n");
ret = -ENODEV;
goto out;
}
host->dma_chan_tx = dma_request_slave_channel(dev, "tx");
if (host->dma_chan_tx == NULL) {
dev_err(dev, "unable to request tx dma channel\n");
ret = -ENODEV;
goto out;
}
if (host->pdata) {
host->detect_delay_ms = host->pdata->detect_delay_ms;
host->power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
if (IS_ERR(host->power)) {
dev_err(dev, "Failed requesting gpio_power\n");
goto out;
}
/* FIXME: should we pass detection delay to debounce? */
ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0, NULL);
if (ret && ret != -ENOENT) {
dev_err(dev, "Failed requesting gpio_cd\n");
goto out;
}
ret = mmc_gpiod_request_ro(mmc, "wp", 0, 0, NULL);
if (ret && ret != -ENOENT) {
dev_err(dev, "Failed requesting gpio_ro\n");
goto out;
}
if (!ret) {
host->use_ro_gpio = true;
mmc->caps2 |= host->pdata->gpio_card_ro_invert ?
0 : MMC_CAP2_RO_ACTIVE_HIGH;
}
if (host->pdata->init)
host->pdata->init(dev, pxamci_detect_irq, mmc);
if (host->power && host->pdata->setpower)
dev_warn(dev, "gpio_power and setpower() both defined\n");
if (host->use_ro_gpio && host->pdata->get_ro)
dev_warn(dev, "gpio_ro and get_ro() both defined\n");
}
mmc_add_host(mmc);
return 0;
out:
if (host) {
if (host->dma_chan_rx)
dma_release_channel(host->dma_chan_rx);
if (host->dma_chan_tx)
dma_release_channel(host->dma_chan_tx);
}
if (mmc)
mmc_free_host(mmc);
return ret;
}
static int pxamci_remove(struct platform_device *pdev)
{
struct mmc_host *mmc = platform_get_drvdata(pdev);
if (mmc) {
struct pxamci_host *host = mmc_priv(mmc);
mmc_remove_host(mmc);
if (host->pdata && host->pdata->exit)
host->pdata->exit(&pdev->dev, mmc);
pxamci_stop_clock(host);
writel(TXFIFO_WR_REQ|RXFIFO_RD_REQ|CLK_IS_OFF|STOP_CMD|
END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
host->base + MMC_I_MASK);
dmaengine_terminate_all(host->dma_chan_rx);
dmaengine_terminate_all(host->dma_chan_tx);
dma_release_channel(host->dma_chan_rx);
dma_release_channel(host->dma_chan_tx);
mmc_free_host(mmc);
}
return 0;
}
static struct platform_driver pxamci_driver = {
.probe = pxamci_probe,
.remove = pxamci_remove,
.driver = {
.name = DRIVER_NAME,
.of_match_table = of_match_ptr(pxa_mmc_dt_ids),
},
};
module_platform_driver(pxamci_driver);
MODULE_DESCRIPTION("PXA Multimedia Card Interface Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-mci");
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