u-boot/drivers/mmc/pxa_mmc_gen.c
Thierry Reding 48972d907a mmc: Implement card detection.
Check for card detect each time an MMC/SD device is initialized. If card
detection is not implemented, this code behaves as before and continues
assuming a card is present. If no card is detected, has_init is reset
for the MMC/SD device (to force initialization next time) and an error
is returned.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Jason Liu <jason.hui@linaro.org>
2012-01-08 21:28:27 -06:00

443 lines
10 KiB
C

/*
* Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
*
* Loosely based on the old code and Linux's PXA MMC driver
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* 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.
*
* 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., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <config.h>
#include <common.h>
#include <malloc.h>
#include <mmc.h>
#include <asm/errno.h>
#include <asm/arch/hardware.h>
#include <asm/arch/regs-mmc.h>
#include <asm/io.h>
/* PXAMMC Generic default config for various CPUs */
#if defined(CONFIG_CPU_PXA25X)
#define PXAMMC_FIFO_SIZE 1
#define PXAMMC_MIN_SPEED 312500
#define PXAMMC_MAX_SPEED 20000000
#define PXAMMC_HOST_CAPS (0)
#elif defined(CONFIG_CPU_PXA27X)
#define PXAMMC_CRC_SKIP
#define PXAMMC_FIFO_SIZE 32
#define PXAMMC_MIN_SPEED 304000
#define PXAMMC_MAX_SPEED 19500000
#define PXAMMC_HOST_CAPS (MMC_MODE_4BIT)
#elif defined(CONFIG_CPU_MONAHANS)
#define PXAMMC_FIFO_SIZE 32
#define PXAMMC_MIN_SPEED 304000
#define PXAMMC_MAX_SPEED 26000000
#define PXAMMC_HOST_CAPS (MMC_MODE_4BIT | MMC_MODE_HS)
#else
#error "This CPU isn't supported by PXA MMC!"
#endif
#define MMC_STAT_ERRORS \
(MMC_STAT_RES_CRC_ERROR | MMC_STAT_SPI_READ_ERROR_TOKEN | \
MMC_STAT_CRC_READ_ERROR | MMC_STAT_TIME_OUT_RESPONSE | \
MMC_STAT_READ_TIME_OUT | MMC_STAT_CRC_WRITE_ERROR)
/* 1 millisecond (in wait cycles below it's 100 x 10uS waits) */
#define PXA_MMC_TIMEOUT 100
struct pxa_mmc_priv {
struct pxa_mmc_regs *regs;
};
/* Wait for bit to be set */
static int pxa_mmc_wait(struct mmc *mmc, uint32_t mask)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
unsigned int timeout = PXA_MMC_TIMEOUT;
/* Wait for bit to be set */
while (--timeout) {
if (readl(&regs->stat) & mask)
break;
udelay(10);
}
if (!timeout)
return -ETIMEDOUT;
return 0;
}
static int pxa_mmc_stop_clock(struct mmc *mmc)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
unsigned int timeout = PXA_MMC_TIMEOUT;
/* If the clock aren't running, exit */
if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
return 0;
/* Tell the controller to turn off the clock */
writel(MMC_STRPCL_STOP_CLK, &regs->strpcl);
/* Wait until the clock are off */
while (--timeout) {
if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
break;
udelay(10);
}
/* The clock refused to stop, scream and die a painful death */
if (!timeout)
return -ETIMEDOUT;
/* The clock stopped correctly */
return 0;
}
static int pxa_mmc_start_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
uint32_t cmdat)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
int ret;
/* The card can send a "busy" response */
if (cmd->flags & MMC_RSP_BUSY)
cmdat |= MMC_CMDAT_BUSY;
/* Inform the controller about response type */
switch (cmd->resp_type) {
case MMC_RSP_R1:
case MMC_RSP_R1b:
cmdat |= MMC_CMDAT_R1;
break;
case MMC_RSP_R2:
cmdat |= MMC_CMDAT_R2;
break;
case MMC_RSP_R3:
cmdat |= MMC_CMDAT_R3;
break;
default:
break;
}
/* Load command and it's arguments into the controller */
writel(cmd->cmdidx, &regs->cmd);
writel(cmd->cmdarg >> 16, &regs->argh);
writel(cmd->cmdarg & 0xffff, &regs->argl);
writel(cmdat, &regs->cmdat);
/* Start the controller clock and wait until they are started */
writel(MMC_STRPCL_START_CLK, &regs->strpcl);
ret = pxa_mmc_wait(mmc, MMC_STAT_CLK_EN);
if (ret)
return ret;
/* Correct and happy end */
return 0;
}
static int pxa_mmc_cmd_done(struct mmc *mmc, struct mmc_cmd *cmd)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
uint32_t a, b, c;
int i;
int stat;
/* Read the controller status */
stat = readl(&regs->stat);
/*
* Linux says:
* Did I mention this is Sick. We always need to
* discard the upper 8 bits of the first 16-bit word.
*/
a = readl(&regs->res) & 0xffff;
for (i = 0; i < 4; i++) {
b = readl(&regs->res) & 0xffff;
c = readl(&regs->res) & 0xffff;
cmd->response[i] = (a << 24) | (b << 8) | (c >> 8);
a = c;
}
/* The command response didn't arrive */
if (stat & MMC_STAT_TIME_OUT_RESPONSE)
return -ETIMEDOUT;
else if (stat & MMC_STAT_RES_CRC_ERROR && cmd->flags & MMC_RSP_CRC) {
#ifdef PXAMMC_CRC_SKIP
if (cmd->flags & MMC_RSP_136 && cmd->response[0] & (1 << 31))
printf("Ignoring CRC, this may be dangerous!\n");
else
#endif
return -EILSEQ;
}
/* The command response was successfully read */
return 0;
}
static int pxa_mmc_do_read_xfer(struct mmc *mmc, struct mmc_data *data)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
uint32_t len;
uint32_t *buf = (uint32_t *)data->dest;
int size;
int ret;
len = data->blocks * data->blocksize;
while (len) {
/* The controller has data ready */
if (readl(&regs->i_reg) & MMC_I_REG_RXFIFO_RD_REQ) {
size = min(len, PXAMMC_FIFO_SIZE);
len -= size;
size /= 4;
/* Read data into the buffer */
while (size--)
*buf++ = readl(&regs->rxfifo);
}
if (readl(&regs->stat) & MMC_STAT_ERRORS)
return -EIO;
}
/* Wait for the transmission-done interrupt */
ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
if (ret)
return ret;
return 0;
}
static int pxa_mmc_do_write_xfer(struct mmc *mmc, struct mmc_data *data)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
uint32_t len;
uint32_t *buf = (uint32_t *)data->src;
int size;
int ret;
len = data->blocks * data->blocksize;
while (len) {
/* The controller is ready to receive data */
if (readl(&regs->i_reg) & MMC_I_REG_TXFIFO_WR_REQ) {
size = min(len, PXAMMC_FIFO_SIZE);
len -= size;
size /= 4;
while (size--)
writel(*buf++, &regs->txfifo);
if (min(len, PXAMMC_FIFO_SIZE) < 32)
writel(MMC_PRTBUF_BUF_PART_FULL, &regs->prtbuf);
}
if (readl(&regs->stat) & MMC_STAT_ERRORS)
return -EIO;
}
/* Wait for the transmission-done interrupt */
ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
if (ret)
return ret;
/* Wait until the data are really written to the card */
ret = pxa_mmc_wait(mmc, MMC_STAT_PRG_DONE);
if (ret)
return ret;
return 0;
}
static int pxa_mmc_request(struct mmc *mmc, struct mmc_cmd *cmd,
struct mmc_data *data)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
uint32_t cmdat = 0;
int ret;
/* Stop the controller */
ret = pxa_mmc_stop_clock(mmc);
if (ret)
return ret;
/* If we're doing data transfer, configure the controller accordingly */
if (data) {
writel(data->blocks, &regs->nob);
writel(data->blocksize, &regs->blklen);
/* This delay can be optimized, but stick with max value */
writel(0xffff, &regs->rdto);
cmdat |= MMC_CMDAT_DATA_EN;
if (data->flags & MMC_DATA_WRITE)
cmdat |= MMC_CMDAT_WRITE;
}
/* Run in 4bit mode if the card can do it */
if (mmc->bus_width == 4)
cmdat |= MMC_CMDAT_SD_4DAT;
/* Execute the command */
ret = pxa_mmc_start_cmd(mmc, cmd, cmdat);
if (ret)
return ret;
/* Wait until the command completes */
ret = pxa_mmc_wait(mmc, MMC_STAT_END_CMD_RES);
if (ret)
return ret;
/* Read back the result */
ret = pxa_mmc_cmd_done(mmc, cmd);
if (ret)
return ret;
/* In case there was a data transfer scheduled, do it */
if (data) {
if (data->flags & MMC_DATA_WRITE)
pxa_mmc_do_write_xfer(mmc, data);
else
pxa_mmc_do_read_xfer(mmc, data);
}
return 0;
}
static void pxa_mmc_set_ios(struct mmc *mmc)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
uint32_t tmp;
uint32_t pxa_mmc_clock;
if (!mmc->clock) {
pxa_mmc_stop_clock(mmc);
return;
}
/* PXA3xx can do 26MHz with special settings. */
if (mmc->clock == 26000000) {
writel(0x7, &regs->clkrt);
return;
}
/* Set clock to the card the usual way. */
pxa_mmc_clock = 0;
tmp = mmc->f_max / mmc->clock;
tmp += tmp % 2;
while (tmp > 1) {
pxa_mmc_clock++;
tmp >>= 1;
}
writel(pxa_mmc_clock, &regs->clkrt);
}
static int pxa_mmc_init(struct mmc *mmc)
{
struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
struct pxa_mmc_regs *regs = priv->regs;
/* Make sure the clock are stopped */
pxa_mmc_stop_clock(mmc);
/* Turn off SPI mode */
writel(0, &regs->spi);
/* Set up maximum timeout to wait for command response */
writel(MMC_RES_TO_MAX_MASK, &regs->resto);
/* Mask all interrupts */
writel(~(MMC_I_MASK_TXFIFO_WR_REQ | MMC_I_MASK_RXFIFO_RD_REQ),
&regs->i_mask);
return 0;
}
int pxa_mmc_register(int card_index)
{
struct mmc *mmc;
struct pxa_mmc_priv *priv;
uint32_t reg;
int ret = -ENOMEM;
mmc = malloc(sizeof(struct mmc));
if (!mmc)
goto err0;
priv = malloc(sizeof(struct pxa_mmc_priv));
if (!priv)
goto err1;
switch (card_index) {
case 0:
priv->regs = (struct pxa_mmc_regs *)MMC0_BASE;
break;
case 1:
priv->regs = (struct pxa_mmc_regs *)MMC1_BASE;
break;
default:
printf("PXA MMC: Invalid MMC controller ID (card_index = %d)\n",
card_index);
goto err2;
}
mmc->priv = priv;
sprintf(mmc->name, "PXA MMC");
mmc->send_cmd = pxa_mmc_request;
mmc->set_ios = pxa_mmc_set_ios;
mmc->init = pxa_mmc_init;
mmc->getcd = NULL;
mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
mmc->f_max = PXAMMC_MAX_SPEED;
mmc->f_min = PXAMMC_MIN_SPEED;
mmc->host_caps = PXAMMC_HOST_CAPS;
mmc->b_max = 0;
#ifndef CONFIG_CPU_MONAHANS /* PXA2xx */
reg = readl(CKEN);
reg |= CKEN12_MMC;
writel(reg, CKEN);
#else /* PXA3xx */
reg = readl(CKENA);
reg |= CKENA_12_MMC0 | CKENA_13_MMC1;
writel(reg, CKENA);
#endif
mmc_register(mmc);
return 0;
err2:
free(priv);
err1:
free(mmc);
err0:
return ret;
}