u-boot/drivers/mmc/gen_atmel_mci.c
Gregory CLEMENT b4670a0c2b mmc: atmel: Properly fix clock configuration
Timing issue occurs on eMMC not only when modifying the frequency but
also for all the switch command(CMD6). According to the MMC spec waiting
8 clocks after a switch command would be the thing to do.

This patch allows fixing CPU hang observed when trying to changing the
bus width on a eMMC on SAMA5D4.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Marek Vasut <marex@denx.de> # on DENX MA5D4EV
Acked-by: Marek Vasut <marex@denx.de>
Tested-by: Andreas Bießmann <andreas.devel@googlemail.com> # on atngw100
Acked-by: Andreas Bießmann <andreas.devel@googlemail.com>
[fixed minor checkpatch warning]
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
2016-01-27 13:58:58 +01:00

457 lines
11 KiB
C

/*
* Copyright (C) 2010
* Rob Emanuele <rob@emanuele.us>
* Reinhard Meyer, EMK Elektronik <reinhard.meyer@emk-elektronik.de>
*
* Original Driver:
* Copyright (C) 2004-2006 Atmel Corporation
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <mmc.h>
#include <part.h>
#include <malloc.h>
#include <asm/io.h>
#include <asm/errno.h>
#include <asm/byteorder.h>
#include <asm/arch/clk.h>
#include <asm/arch/hardware.h>
#include "atmel_mci.h"
#ifndef CONFIG_SYS_MMC_CLK_OD
# define CONFIG_SYS_MMC_CLK_OD 150000
#endif
#define MMC_DEFAULT_BLKLEN 512
#if defined(CONFIG_ATMEL_MCI_PORTB)
# define MCI_BUS 1
#else
# define MCI_BUS 0
#endif
struct atmel_mci_priv {
struct mmc_config cfg;
struct atmel_mci *mci;
unsigned int initialized:1;
unsigned int curr_clk;
};
/* Read Atmel MCI IP version */
static unsigned int atmel_mci_get_version(struct atmel_mci *mci)
{
return readl(&mci->version) & 0x00000fff;
}
/*
* Print command and status:
*
* - always when DEBUG is defined
* - on command errors
*/
static void dump_cmd(u32 cmdr, u32 arg, u32 status, const char* msg)
{
debug("gen_atmel_mci: CMDR %08x (%2u) ARGR %08x (SR: %08x) %s\n",
cmdr, cmdr & 0x3F, arg, status, msg);
}
/* Setup for MCI Clock and Block Size */
static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen)
{
struct atmel_mci_priv *priv = mmc->priv;
atmel_mci_t *mci = priv->mci;
u32 bus_hz = get_mci_clk_rate();
u32 clkdiv = 255;
unsigned int version = atmel_mci_get_version(mci);
u32 clkodd = 0;
u32 mr;
debug("mci: bus_hz is %u, setting clock %u Hz, block size %u\n",
bus_hz, hz, blklen);
if (hz > 0) {
if (version >= 0x500) {
clkdiv = DIV_ROUND_UP(bus_hz, hz) - 2;
if (clkdiv > 511)
clkdiv = 511;
clkodd = clkdiv & 1;
clkdiv >>= 1;
debug("mci: setting clock %u Hz, block size %u\n",
bus_hz / (clkdiv * 2 + clkodd + 2), blklen);
} else {
/* find clkdiv yielding a rate <= than requested */
for (clkdiv = 0; clkdiv < 255; clkdiv++) {
if ((bus_hz / (clkdiv + 1) / 2) <= hz)
break;
}
debug("mci: setting clock %u Hz, block size %u\n",
(bus_hz / (clkdiv + 1)) / 2, blklen);
}
}
if (version >= 0x500)
priv->curr_clk = bus_hz / (clkdiv * 2 + clkodd + 2);
else
priv->curr_clk = (bus_hz / (clkdiv + 1)) / 2;
blklen &= 0xfffc;
mr = MMCI_BF(CLKDIV, clkdiv);
/* MCI IP version >= 0x200 has R/WPROOF */
if (version >= 0x200)
mr |= MMCI_BIT(RDPROOF) | MMCI_BIT(WRPROOF);
/*
* MCI IP version >= 0x500 use bit 16 as clkodd.
* MCI IP version < 0x500 use upper 16 bits for blklen.
*/
if (version >= 0x500)
mr |= MMCI_BF(CLKODD, clkodd);
else
mr |= MMCI_BF(BLKLEN, blklen);
writel(mr, &mci->mr);
/* MCI IP version >= 0x200 has blkr */
if (version >= 0x200)
writel(MMCI_BF(BLKLEN, blklen), &mci->blkr);
if (mmc->card_caps & mmc->cfg->host_caps & MMC_MODE_HS)
writel(MMCI_BIT(HSMODE), &mci->cfg);
priv->initialized = 1;
}
/* Return the CMDR with flags for a given command and data packet */
static u32 mci_encode_cmd(
struct mmc_cmd *cmd, struct mmc_data *data, u32* error_flags)
{
u32 cmdr = 0;
/* Default Flags for Errors */
*error_flags |= (MMCI_BIT(DTOE) | MMCI_BIT(RDIRE) | MMCI_BIT(RENDE) |
MMCI_BIT(RINDE) | MMCI_BIT(RTOE));
/* Default Flags for the Command */
cmdr |= MMCI_BIT(MAXLAT);
if (data) {
cmdr |= MMCI_BF(TRCMD, 1);
if (data->blocks > 1)
cmdr |= MMCI_BF(TRTYP, 1);
if (data->flags & MMC_DATA_READ)
cmdr |= MMCI_BIT(TRDIR);
}
if (cmd->resp_type & MMC_RSP_CRC)
*error_flags |= MMCI_BIT(RCRCE);
if (cmd->resp_type & MMC_RSP_136)
cmdr |= MMCI_BF(RSPTYP, 2);
else if (cmd->resp_type & MMC_RSP_BUSY)
cmdr |= MMCI_BF(RSPTYP, 3);
else if (cmd->resp_type & MMC_RSP_PRESENT)
cmdr |= MMCI_BF(RSPTYP, 1);
return cmdr | MMCI_BF(CMDNB, cmd->cmdidx);
}
/* Entered into function pointer in mci_send_cmd */
static u32 mci_data_read(atmel_mci_t *mci, u32* data, u32 error_flags)
{
u32 status;
do {
status = readl(&mci->sr);
if (status & (error_flags | MMCI_BIT(OVRE)))
goto io_fail;
} while (!(status & MMCI_BIT(RXRDY)));
if (status & MMCI_BIT(RXRDY)) {
*data = readl(&mci->rdr);
status = 0;
}
io_fail:
return status;
}
/* Entered into function pointer in mci_send_cmd */
static u32 mci_data_write(atmel_mci_t *mci, u32* data, u32 error_flags)
{
u32 status;
do {
status = readl(&mci->sr);
if (status & (error_flags | MMCI_BIT(UNRE)))
goto io_fail;
} while (!(status & MMCI_BIT(TXRDY)));
if (status & MMCI_BIT(TXRDY)) {
writel(*data, &mci->tdr);
status = 0;
}
io_fail:
return status;
}
/*
* Entered into mmc structure during driver init
*
* Sends a command out on the bus and deals with the block data.
* Takes the mmc pointer, a command pointer, and an optional data pointer.
*/
static int
mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
{
struct atmel_mci_priv *priv = mmc->priv;
atmel_mci_t *mci = priv->mci;
u32 cmdr;
u32 error_flags = 0;
u32 status;
if (!priv->initialized) {
puts ("MCI not initialized!\n");
return COMM_ERR;
}
/* Figure out the transfer arguments */
cmdr = mci_encode_cmd(cmd, data, &error_flags);
/* For multi blocks read/write, set the block register */
if ((cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK)
|| (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK))
writel(data->blocks | MMCI_BF(BLKLEN, mmc->read_bl_len),
&mci->blkr);
/* Send the command */
writel(cmd->cmdarg, &mci->argr);
writel(cmdr, &mci->cmdr);
#ifdef DEBUG
dump_cmd(cmdr, cmd->cmdarg, 0, "DEBUG");
#endif
/* Wait for the command to complete */
while (!((status = readl(&mci->sr)) & MMCI_BIT(CMDRDY)));
if ((status & error_flags) & MMCI_BIT(RTOE)) {
dump_cmd(cmdr, cmd->cmdarg, status, "Command Time Out");
return TIMEOUT;
} else if (status & error_flags) {
dump_cmd(cmdr, cmd->cmdarg, status, "Command Failed");
return COMM_ERR;
}
/* Copy the response to the response buffer */
if (cmd->resp_type & MMC_RSP_136) {
cmd->response[0] = readl(&mci->rspr);
cmd->response[1] = readl(&mci->rspr1);
cmd->response[2] = readl(&mci->rspr2);
cmd->response[3] = readl(&mci->rspr3);
} else
cmd->response[0] = readl(&mci->rspr);
/* transfer all of the blocks */
if (data) {
u32 word_count, block_count;
u32* ioptr;
u32 sys_blocksize, dummy, i;
u32 (*mci_data_op)
(atmel_mci_t *mci, u32* data, u32 error_flags);
if (data->flags & MMC_DATA_READ) {
mci_data_op = mci_data_read;
sys_blocksize = mmc->read_bl_len;
ioptr = (u32*)data->dest;
} else {
mci_data_op = mci_data_write;
sys_blocksize = mmc->write_bl_len;
ioptr = (u32*)data->src;
}
status = 0;
for (block_count = 0;
block_count < data->blocks && !status;
block_count++) {
word_count = 0;
do {
status = mci_data_op(mci, ioptr, error_flags);
word_count++;
ioptr++;
} while (!status && word_count < (data->blocksize/4));
#ifdef DEBUG
if (data->flags & MMC_DATA_READ)
{
u32 cnt = word_count * 4;
printf("Read Data:\n");
print_buffer(0, data->dest + cnt * block_count,
1, cnt, 0);
}
#endif
#ifdef DEBUG
if (!status && word_count < (sys_blocksize / 4))
printf("filling rest of block...\n");
#endif
/* fill the rest of a full block */
while (!status && word_count < (sys_blocksize / 4)) {
status = mci_data_op(mci, &dummy,
error_flags);
word_count++;
}
if (status) {
dump_cmd(cmdr, cmd->cmdarg, status,
"Data Transfer Failed");
return COMM_ERR;
}
}
/* Wait for Transfer End */
i = 0;
do {
status = readl(&mci->sr);
if (status & error_flags) {
dump_cmd(cmdr, cmd->cmdarg, status,
"DTIP Wait Failed");
return COMM_ERR;
}
i++;
} while ((status & MMCI_BIT(DTIP)) && i < 10000);
if (status & MMCI_BIT(DTIP)) {
dump_cmd(cmdr, cmd->cmdarg, status,
"XFER DTIP never unset, ignoring");
}
}
/*
* After the switch command, wait for 8 clocks before the next
* command
*/
if (cmd->cmdidx == MMC_CMD_SWITCH)
udelay(8*1000000 / priv->curr_clk); /* 8 clk in us */
return 0;
}
/* Entered into mmc structure during driver init */
static void mci_set_ios(struct mmc *mmc)
{
struct atmel_mci_priv *priv = mmc->priv;
atmel_mci_t *mci = priv->mci;
int bus_width = mmc->bus_width;
unsigned int version = atmel_mci_get_version(mci);
int busw;
/* Set the clock speed */
mci_set_mode(mmc, mmc->clock, MMC_DEFAULT_BLKLEN);
/*
* set the bus width and select slot for this interface
* there is no capability for multiple slots on the same interface yet
*/
if ((version & 0xf00) >= 0x300) {
switch (bus_width) {
case 8:
busw = 3;
break;
case 4:
busw = 2;
break;
default:
busw = 0;
break;
}
writel(busw << 6 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
} else {
busw = (bus_width == 4) ? 1 : 0;
writel(busw << 7 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
}
}
/* Entered into mmc structure during driver init */
static int mci_init(struct mmc *mmc)
{
struct atmel_mci_priv *priv = mmc->priv;
atmel_mci_t *mci = priv->mci;
/* Initialize controller */
writel(MMCI_BIT(SWRST), &mci->cr); /* soft reset */
writel(MMCI_BIT(PWSDIS), &mci->cr); /* disable power save */
writel(MMCI_BIT(MCIEN), &mci->cr); /* enable mci */
writel(MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr); /* select port */
/* This delay can be optimized, but stick with max value */
writel(0x7f, &mci->dtor);
/* Disable Interrupts */
writel(~0UL, &mci->idr);
/* Set default clocks and blocklen */
mci_set_mode(mmc, CONFIG_SYS_MMC_CLK_OD, MMC_DEFAULT_BLKLEN);
return 0;
}
static const struct mmc_ops atmel_mci_ops = {
.send_cmd = mci_send_cmd,
.set_ios = mci_set_ios,
.init = mci_init,
};
/*
* This is the only exported function
*
* Call it with the MCI register base address
*/
int atmel_mci_init(void *regs)
{
struct mmc *mmc;
struct mmc_config *cfg;
struct atmel_mci_priv *priv;
unsigned int version;
priv = calloc(1, sizeof(*priv));
if (!priv)
return -ENOMEM;
cfg = &priv->cfg;
cfg->name = "mci";
cfg->ops = &atmel_mci_ops;
priv->mci = (struct atmel_mci *)regs;
priv->initialized = 0;
/* need to be able to pass these in on a board by board basis */
cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
version = atmel_mci_get_version(priv->mci);
if ((version & 0xf00) >= 0x300) {
cfg->host_caps = MMC_MODE_8BIT;
cfg->host_caps |= MMC_MODE_HS | MMC_MODE_HS_52MHz;
}
cfg->host_caps |= MMC_MODE_4BIT;
/*
* min and max frequencies determined by
* max and min of clock divider
*/
cfg->f_min = get_mci_clk_rate() / (2*256);
cfg->f_max = get_mci_clk_rate() / (2*1);
cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
mmc = mmc_create(cfg, priv);
if (mmc == NULL) {
free(priv);
return -ENODEV;
}
/* NOTE: possibly leaking the priv structure */
return 0;
}