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u-boot/drivers/mmc/bcm2835_sdhost.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style 
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

977 lines
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// SPDX-License-Identifier: GPL-2.0
/*
* bcm2835 sdhost driver.
*
* The 2835 has two SD controllers: The Arasan sdhci controller
* (supported by the iproc driver) and a custom sdhost controller
* (supported by this driver).
*
* The sdhci controller supports both sdcard and sdio. The sdhost
* controller supports the sdcard only, but has better performance.
* Also note that the rpi3 has sdio wifi, so driving the sdcard with
* the sdhost controller allows to use the sdhci controller for wifi
* support.
*
* The configuration is done by devicetree via pin muxing. Both
* SD controller are available on the same pins (2 pin groups = pin 22
* to 27 + pin 48 to 53). So it's possible to use both SD controllers
* at the same time with different pin groups.
*
* This code was ported to U-Boot by
* Alexander Graf <agraf@suse.de>
* and is based on drivers/mmc/host/bcm2835.c in Linux which is written by
* Phil Elwell <phil@raspberrypi.org>
* Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
* which is based on
* mmc-bcm2835.c by Gellert Weisz
* which is, in turn, based on
* sdhci-bcm2708.c by Broadcom
* sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
* sdhci.c and sdhci-pci.c by Pierre Ossman
*/
#include <clk.h>
#include <common.h>
#include <dm.h>
#include <mmc.h>
#include <asm/arch/msg.h>
#include <asm/arch/mbox.h>
#include <asm/unaligned.h>
#include <linux/compat.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/sizes.h>
#include <mach/gpio.h>
#include <power/regulator.h>
#define msleep(a) udelay(a * 1000)
#define SDCMD 0x00 /* Command to SD card - 16 R/W */
#define SDARG 0x04 /* Argument to SD card - 32 R/W */
#define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
#define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */
#define SDRSP0 0x10 /* SD card response (31:0) - 32 R */
#define SDRSP1 0x14 /* SD card response (63:32) - 32 R */
#define SDRSP2 0x18 /* SD card response (95:64) - 32 R */
#define SDRSP3 0x1c /* SD card response (127:96) - 32 R */
#define SDHSTS 0x20 /* SD host status - 11 R/W */
#define SDVDD 0x30 /* SD card power control - 1 R/W */
#define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */
#define SDHCFG 0x38 /* Host configuration - 2 R/W */
#define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */
#define SDDATA 0x40 /* Data to/from SD card - 32 R/W */
#define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */
#define SDCMD_NEW_FLAG 0x8000
#define SDCMD_FAIL_FLAG 0x4000
#define SDCMD_BUSYWAIT 0x800
#define SDCMD_NO_RESPONSE 0x400
#define SDCMD_LONG_RESPONSE 0x200
#define SDCMD_WRITE_CMD 0x80
#define SDCMD_READ_CMD 0x40
#define SDCMD_CMD_MASK 0x3f
#define SDCDIV_MAX_CDIV 0x7ff
#define SDHSTS_BUSY_IRPT 0x400
#define SDHSTS_BLOCK_IRPT 0x200
#define SDHSTS_SDIO_IRPT 0x100
#define SDHSTS_REW_TIME_OUT 0x80
#define SDHSTS_CMD_TIME_OUT 0x40
#define SDHSTS_CRC16_ERROR 0x20
#define SDHSTS_CRC7_ERROR 0x10
#define SDHSTS_FIFO_ERROR 0x08
#define SDHSTS_DATA_FLAG 0x01
#define SDHSTS_CLEAR_MASK (SDHSTS_BUSY_IRPT | \
SDHSTS_BLOCK_IRPT | \
SDHSTS_SDIO_IRPT | \
SDHSTS_REW_TIME_OUT | \
SDHSTS_CMD_TIME_OUT | \
SDHSTS_CRC16_ERROR | \
SDHSTS_CRC7_ERROR | \
SDHSTS_FIFO_ERROR)
#define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \
SDHSTS_CRC16_ERROR | \
SDHSTS_REW_TIME_OUT | \
SDHSTS_FIFO_ERROR)
#define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \
SDHSTS_TRANSFER_ERROR_MASK)
#define SDHCFG_BUSY_IRPT_EN BIT(10)
#define SDHCFG_BLOCK_IRPT_EN BIT(8)
#define SDHCFG_SDIO_IRPT_EN BIT(5)
#define SDHCFG_DATA_IRPT_EN BIT(4)
#define SDHCFG_SLOW_CARD BIT(3)
#define SDHCFG_WIDE_EXT_BUS BIT(2)
#define SDHCFG_WIDE_INT_BUS BIT(1)
#define SDHCFG_REL_CMD_LINE BIT(0)
#define SDVDD_POWER_OFF 0
#define SDVDD_POWER_ON 1
#define SDEDM_FORCE_DATA_MODE BIT(19)
#define SDEDM_CLOCK_PULSE BIT(20)
#define SDEDM_BYPASS BIT(21)
#define SDEDM_FIFO_FILL_SHIFT 4
#define SDEDM_FIFO_FILL_MASK 0x1f
static u32 edm_fifo_fill(u32 edm)
{
return (edm >> SDEDM_FIFO_FILL_SHIFT) & SDEDM_FIFO_FILL_MASK;
}
#define SDEDM_WRITE_THRESHOLD_SHIFT 9
#define SDEDM_READ_THRESHOLD_SHIFT 14
#define SDEDM_THRESHOLD_MASK 0x1f
#define SDEDM_FSM_MASK 0xf
#define SDEDM_FSM_IDENTMODE 0x0
#define SDEDM_FSM_DATAMODE 0x1
#define SDEDM_FSM_READDATA 0x2
#define SDEDM_FSM_WRITEDATA 0x3
#define SDEDM_FSM_READWAIT 0x4
#define SDEDM_FSM_READCRC 0x5
#define SDEDM_FSM_WRITECRC 0x6
#define SDEDM_FSM_WRITEWAIT1 0x7
#define SDEDM_FSM_POWERDOWN 0x8
#define SDEDM_FSM_POWERUP 0x9
#define SDEDM_FSM_WRITESTART1 0xa
#define SDEDM_FSM_WRITESTART2 0xb
#define SDEDM_FSM_GENPULSES 0xc
#define SDEDM_FSM_WRITEWAIT2 0xd
#define SDEDM_FSM_STARTPOWDOWN 0xf
#define SDDATA_FIFO_WORDS 16
#define FIFO_READ_THRESHOLD 4
#define FIFO_WRITE_THRESHOLD 4
#define SDDATA_FIFO_PIO_BURST 8
#define SDHST_TIMEOUT_MAX_USEC 100000
struct bcm2835_plat {
struct mmc_config cfg;
struct mmc mmc;
};
struct bcm2835_host {
void __iomem *ioaddr;
u32 phys_addr;
int clock; /* Current clock speed */
unsigned int max_clk; /* Max possible freq */
unsigned int blocks; /* remaining PIO blocks */
int irq; /* Device IRQ */
u32 ns_per_fifo_word;
/* cached registers */
u32 hcfg;
u32 cdiv;
struct mmc_cmd *cmd; /* Current command */
struct mmc_data *data; /* Current data request */
bool data_complete:1;/* Data finished before cmd */
bool use_busy:1; /* Wait for busy interrupt */
bool wait_data_complete:1; /* Wait for data */
/* for threaded irq handler */
bool irq_block;
bool irq_busy;
bool irq_data;
struct udevice *dev;
struct mmc *mmc;
struct bcm2835_plat *plat;
};
static void bcm2835_dumpregs(struct bcm2835_host *host)
{
dev_dbg(dev, "=========== REGISTER DUMP ===========\n");
dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD));
dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG));
dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));
dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));
dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));
dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));
dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));
dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));
dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));
dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD));
dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM));
dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));
dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));
dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));
dev_dbg(dev, "===========================================\n");
}
static void bcm2835_reset_internal(struct bcm2835_host *host)
{
u32 temp;
writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
writel(0, host->ioaddr + SDCMD);
writel(0, host->ioaddr + SDARG);
/* Set timeout to a big enough value so we don't hit it */
writel(0xf00000, host->ioaddr + SDTOUT);
writel(0, host->ioaddr + SDCDIV);
/* Clear status register */
writel(SDHSTS_CLEAR_MASK, host->ioaddr + SDHSTS);
writel(0, host->ioaddr + SDHCFG);
writel(0, host->ioaddr + SDHBCT);
writel(0, host->ioaddr + SDHBLC);
/* Limit fifo usage due to silicon bug */
temp = readl(host->ioaddr + SDEDM);
temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
(SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
(FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
writel(temp, host->ioaddr + SDEDM);
/* Wait for FIFO threshold to populate */
msleep(20);
writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);
/* Wait for all components to go through power on cycle */
msleep(20);
host->clock = 0;
writel(host->hcfg, host->ioaddr + SDHCFG);
writel(host->cdiv, host->ioaddr + SDCDIV);
}
static int bcm2835_finish_command(struct bcm2835_host *host);
static void bcm2835_wait_transfer_complete(struct bcm2835_host *host)
{
int timediff;
u32 alternate_idle;
alternate_idle = (host->data->flags & MMC_DATA_READ) ?
SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;
timediff = 0;
while (1) {
u32 edm, fsm;
edm = readl(host->ioaddr + SDEDM);
fsm = edm & SDEDM_FSM_MASK;
if ((fsm == SDEDM_FSM_IDENTMODE) ||
(fsm == SDEDM_FSM_DATAMODE))
break;
if (fsm == alternate_idle) {
writel(edm | SDEDM_FORCE_DATA_MODE,
host->ioaddr + SDEDM);
break;
}
/* Error out after 100000 register reads (~1s) */
if (timediff++ == 100000) {
dev_err(host->dev,
"wait_transfer_complete - still waiting after %d retries\n",
timediff);
bcm2835_dumpregs(host);
return;
}
}
}
static int bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)
{
struct mmc_data *data = host->data;
size_t blksize = data->blocksize;
int copy_words;
u32 hsts = 0;
u32 *buf;
if (blksize % sizeof(u32))
return -EINVAL;
buf = is_read ? (u32 *)data->dest : (u32 *)data->src;
if (is_read)
data->dest += blksize;
else
data->src += blksize;
copy_words = blksize / sizeof(u32);
/*
* Copy all contents from/to the FIFO as far as it reaches,
* then wait for it to fill/empty again and rewind.
*/
while (copy_words) {
int burst_words, words;
u32 edm;
burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);
edm = readl(host->ioaddr + SDEDM);
if (is_read)
words = edm_fifo_fill(edm);
else
words = SDDATA_FIFO_WORDS - edm_fifo_fill(edm);
if (words < burst_words) {
int fsm_state = (edm & SDEDM_FSM_MASK);
if ((is_read &&
(fsm_state != SDEDM_FSM_READDATA &&
fsm_state != SDEDM_FSM_READWAIT &&
fsm_state != SDEDM_FSM_READCRC)) ||
(!is_read &&
(fsm_state != SDEDM_FSM_WRITEDATA &&
fsm_state != SDEDM_FSM_WRITESTART1 &&
fsm_state != SDEDM_FSM_WRITESTART2))) {
hsts = readl(host->ioaddr + SDHSTS);
printf("fsm %x, hsts %08x\n", fsm_state, hsts);
if (hsts & SDHSTS_ERROR_MASK)
break;
}
continue;
} else if (words > copy_words) {
words = copy_words;
}
copy_words -= words;
/* Copy current chunk to/from the FIFO */
while (words) {
if (is_read)
*(buf++) = readl(host->ioaddr + SDDATA);
else
writel(*(buf++), host->ioaddr + SDDATA);
words--;
}
}
return 0;
}
static int bcm2835_transfer_pio(struct bcm2835_host *host)
{
u32 sdhsts;
bool is_read;
int ret = 0;
is_read = (host->data->flags & MMC_DATA_READ) != 0;
ret = bcm2835_transfer_block_pio(host, is_read);
if (host->wait_data_complete)
bcm2835_wait_transfer_complete(host);
sdhsts = readl(host->ioaddr + SDHSTS);
if (sdhsts & (SDHSTS_CRC16_ERROR |
SDHSTS_CRC7_ERROR |
SDHSTS_FIFO_ERROR)) {
printf("%s transfer error - HSTS %08x\n",
is_read ? "read" : "write", sdhsts);
ret = -EILSEQ;
} else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
SDHSTS_REW_TIME_OUT))) {
printf("%s timeout error - HSTS %08x\n",
is_read ? "read" : "write", sdhsts);
ret = -ETIMEDOUT;
}
return ret;
}
static void bcm2835_set_transfer_irqs(struct bcm2835_host *host)
{
u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |
SDHCFG_BUSY_IRPT_EN;
host->hcfg = (host->hcfg & ~all_irqs) |
SDHCFG_DATA_IRPT_EN |
SDHCFG_BUSY_IRPT_EN;
writel(host->hcfg, host->ioaddr + SDHCFG);
}
static
void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_cmd *cmd,
struct mmc_data *data)
{
WARN_ON(host->data);
host->data = data;
if (!data)
return;
host->wait_data_complete = cmd->cmdidx != MMC_CMD_READ_MULTIPLE_BLOCK;
host->data_complete = false;
/* Use PIO */
host->blocks = data->blocks;
bcm2835_set_transfer_irqs(host);
writel(data->blocksize, host->ioaddr + SDHBCT);
writel(data->blocks, host->ioaddr + SDHBLC);
}
static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host)
{
u32 value;
int ret;
int timeout_us = SDHST_TIMEOUT_MAX_USEC;
ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
!(value & SDCMD_NEW_FLAG), timeout_us);
if (ret == -ETIMEDOUT)
printf("%s: timeout (%d us)\n", __func__, timeout_us);
return value;
}
static int bcm2835_send_command(struct bcm2835_host *host, struct mmc_cmd *cmd,
struct mmc_data *data)
{
u32 sdcmd, sdhsts;
WARN_ON(host->cmd);
if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY)) {
printf("unsupported response type!\n");
return -EINVAL;
}
sdcmd = bcm2835_read_wait_sdcmd(host);
if (sdcmd & SDCMD_NEW_FLAG) {
printf("previous command never completed.\n");
bcm2835_dumpregs(host);
return -EBUSY;
}
host->cmd = cmd;
/* Clear any error flags */
sdhsts = readl(host->ioaddr + SDHSTS);
if (sdhsts & SDHSTS_ERROR_MASK)
writel(sdhsts, host->ioaddr + SDHSTS);
bcm2835_prepare_data(host, cmd, data);
writel(cmd->cmdarg, host->ioaddr + SDARG);
sdcmd = cmd->cmdidx & SDCMD_CMD_MASK;
host->use_busy = false;
if (!(cmd->resp_type & MMC_RSP_PRESENT)) {
sdcmd |= SDCMD_NO_RESPONSE;
} else {
if (cmd->resp_type & MMC_RSP_136)
sdcmd |= SDCMD_LONG_RESPONSE;
if (cmd->resp_type & MMC_RSP_BUSY) {
sdcmd |= SDCMD_BUSYWAIT;
host->use_busy = true;
}
}
if (data) {
if (data->flags & MMC_DATA_WRITE)
sdcmd |= SDCMD_WRITE_CMD;
if (data->flags & MMC_DATA_READ)
sdcmd |= SDCMD_READ_CMD;
}
writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);
return 0;
}
static int bcm2835_transfer_complete(struct bcm2835_host *host)
{
int ret = 0;
WARN_ON(!host->data_complete);
host->data = NULL;
return ret;
}
static void bcm2835_finish_data(struct bcm2835_host *host)
{
host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
writel(host->hcfg, host->ioaddr + SDHCFG);
host->data_complete = true;
if (host->cmd) {
/* Data managed to finish before the
* command completed. Make sure we do
* things in the proper order.
*/
dev_dbg(dev, "Finished early - HSTS %08x\n",
readl(host->ioaddr + SDHSTS));
} else {
bcm2835_transfer_complete(host);
}
}
static int bcm2835_finish_command(struct bcm2835_host *host)
{
struct mmc_cmd *cmd = host->cmd;
u32 sdcmd;
int ret = 0;
sdcmd = bcm2835_read_wait_sdcmd(host);
/* Check for errors */
if (sdcmd & SDCMD_NEW_FLAG) {
printf("command never completed.\n");
bcm2835_dumpregs(host);
return -EIO;
} else if (sdcmd & SDCMD_FAIL_FLAG) {
u32 sdhsts = readl(host->ioaddr + SDHSTS);
/* Clear the errors */
writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);
if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
(host->cmd->cmdidx != MMC_CMD_SEND_OP_COND)) {
if (sdhsts & SDHSTS_CMD_TIME_OUT) {
ret = -ETIMEDOUT;
} else {
printf("unexpected command %d error\n",
host->cmd->cmdidx);
bcm2835_dumpregs(host);
ret = -EILSEQ;
}
return ret;
}
}
if (cmd->resp_type & MMC_RSP_PRESENT) {
if (cmd->resp_type & MMC_RSP_136) {
int i;
for (i = 0; i < 4; i++) {
cmd->response[3 - i] =
readl(host->ioaddr + SDRSP0 + i * 4);
}
} else {
cmd->response[0] = readl(host->ioaddr + SDRSP0);
}
}
/* Processed actual command. */
host->cmd = NULL;
if (host->data && host->data_complete)
ret = bcm2835_transfer_complete(host);
return ret;
}
static int bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
{
int ret = -EINVAL;
if (!(intmask & SDHSTS_ERROR_MASK))
return 0;
if (!host->cmd)
return -EINVAL;
printf("sdhost_busy_irq: intmask %08x\n", intmask);
if (intmask & SDHSTS_CRC7_ERROR) {
ret = -EILSEQ;
} else if (intmask & (SDHSTS_CRC16_ERROR |
SDHSTS_FIFO_ERROR)) {
ret = -EILSEQ;
} else if (intmask & (SDHSTS_REW_TIME_OUT | SDHSTS_CMD_TIME_OUT)) {
ret = -ETIMEDOUT;
}
bcm2835_dumpregs(host);
return ret;
}
static int bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
{
int ret = 0;
if (!host->data)
return 0;
if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
ret = -EILSEQ;
if (intmask & SDHSTS_REW_TIME_OUT)
ret = -ETIMEDOUT;
if (ret)
printf("%s:%d %d\n", __func__, __LINE__, ret);
return ret;
}
static void bcm2835_busy_irq(struct bcm2835_host *host)
{
if (WARN_ON(!host->cmd)) {
bcm2835_dumpregs(host);
return;
}
if (WARN_ON(!host->use_busy)) {
bcm2835_dumpregs(host);
return;
}
host->use_busy = false;
bcm2835_finish_command(host);
}
static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask)
{
int ret;
/*
* There are no dedicated data/space available interrupt
* status bits, so it is necessary to use the single shared
* data/space available FIFO status bits. It is therefore not
* an error to get here when there is no data transfer in
* progress.
*/
if (!host->data)
return;
ret = bcm2835_check_data_error(host, intmask);
if (ret)
goto finished;
if (host->data->flags & MMC_DATA_WRITE) {
/* Use the block interrupt for writes after the first block */
host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);
host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
writel(host->hcfg, host->ioaddr + SDHCFG);
bcm2835_transfer_pio(host);
} else {
bcm2835_transfer_pio(host);
host->blocks--;
if ((host->blocks == 0))
goto finished;
}
return;
finished:
host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
writel(host->hcfg, host->ioaddr + SDHCFG);
}
static void bcm2835_data_threaded_irq(struct bcm2835_host *host)
{
if (!host->data)
return;
if ((host->blocks == 0))
bcm2835_finish_data(host);
}
static void bcm2835_block_irq(struct bcm2835_host *host)
{
if (WARN_ON(!host->data)) {
bcm2835_dumpregs(host);
return;
}
WARN_ON(!host->blocks);
if ((--host->blocks == 0))
bcm2835_finish_data(host);
else
bcm2835_transfer_pio(host);
}
static irqreturn_t bcm2835_irq(int irq, void *dev_id)
{
irqreturn_t result = IRQ_NONE;
struct bcm2835_host *host = dev_id;
u32 intmask;
intmask = readl(host->ioaddr + SDHSTS);
writel(SDHSTS_BUSY_IRPT |
SDHSTS_BLOCK_IRPT |
SDHSTS_SDIO_IRPT |
SDHSTS_DATA_FLAG,
host->ioaddr + SDHSTS);
if (intmask & SDHSTS_BLOCK_IRPT) {
bcm2835_check_data_error(host, intmask);
host->irq_block = true;
result = IRQ_WAKE_THREAD;
}
if (intmask & SDHSTS_BUSY_IRPT) {
if (!bcm2835_check_cmd_error(host, intmask)) {
host->irq_busy = true;
result = IRQ_WAKE_THREAD;
} else {
result = IRQ_HANDLED;
}
}
/* There is no true data interrupt status bit, so it is
* necessary to qualify the data flag with the interrupt
* enable bit.
*/
if ((intmask & SDHSTS_DATA_FLAG) &&
(host->hcfg & SDHCFG_DATA_IRPT_EN)) {
bcm2835_data_irq(host, intmask);
host->irq_data = true;
result = IRQ_WAKE_THREAD;
}
return result;
}
static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id)
{
struct bcm2835_host *host = dev_id;
if (host->irq_block) {
host->irq_block = false;
bcm2835_block_irq(host);
}
if (host->irq_busy) {
host->irq_busy = false;
bcm2835_busy_irq(host);
}
if (host->irq_data) {
host->irq_data = false;
bcm2835_data_threaded_irq(host);
}
return IRQ_HANDLED;
}
static void bcm2835_irq_poll(struct bcm2835_host *host)
{
u32 intmask;
while (1) {
intmask = readl(host->ioaddr + SDHSTS);
if (intmask & (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT |
SDHSTS_SDIO_IRPT | SDHSTS_DATA_FLAG)) {
bcm2835_irq(0, host);
bcm2835_threaded_irq(0, host);
return;
}
}
}
static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
{
int div;
/* The SDCDIV register has 11 bits, and holds (div - 2). But
* in data mode the max is 50MHz wihout a minimum, and only
* the bottom 3 bits are used. Since the switch over is
* automatic (unless we have marked the card as slow...),
* chosen values have to make sense in both modes. Ident mode
* must be 100-400KHz, so can range check the requested
* clock. CMD15 must be used to return to data mode, so this
* can be monitored.
*
* clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
* 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
*
* 623->400KHz/27.8MHz
* reset value (507)->491159/50MHz
*
* BUT, the 3-bit clock divisor in data mode is too small if
* the core clock is higher than 250MHz, so instead use the
* SLOW_CARD configuration bit to force the use of the ident
* clock divisor at all times.
*/
if (clock < 100000) {
/* Can't stop the clock, but make it as slow as possible
* to show willing
*/
host->cdiv = SDCDIV_MAX_CDIV;
writel(host->cdiv, host->ioaddr + SDCDIV);
return;
}
div = host->max_clk / clock;
if (div < 2)
div = 2;
if ((host->max_clk / div) > clock)
div++;
div -= 2;
if (div > SDCDIV_MAX_CDIV)
div = SDCDIV_MAX_CDIV;
clock = host->max_clk / (div + 2);
host->mmc->clock = clock;
/* Calibrate some delays */
host->ns_per_fifo_word = (1000000000 / clock) *
((host->mmc->card_caps & MMC_MODE_4BIT) ? 8 : 32);
host->cdiv = div;
writel(host->cdiv, host->ioaddr + SDCDIV);
/* Set the timeout to 500ms */
writel(host->mmc->clock / 2, host->ioaddr + SDTOUT);
}
static inline int is_power_of_2(u64 x)
{
return !(x & (x - 1));
}
static int bcm2835_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
struct mmc_data *data)
{
struct bcm2835_host *host = dev_get_priv(dev);
u32 edm, fsm;
int ret = 0;
if (data && !is_power_of_2(data->blocksize)) {
printf("unsupported block size (%d bytes)\n", data->blocksize);
if (cmd)
return -EINVAL;
}
edm = readl(host->ioaddr + SDEDM);
fsm = edm & SDEDM_FSM_MASK;
if ((fsm != SDEDM_FSM_IDENTMODE) &&
(fsm != SDEDM_FSM_DATAMODE) &&
(cmd && cmd->cmdidx != MMC_CMD_STOP_TRANSMISSION)) {
printf("previous command (%d) not complete (EDM %08x)\n",
readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, edm);
bcm2835_dumpregs(host);
if (cmd)
return -EILSEQ;
return 0;
}
if (cmd) {
ret = bcm2835_send_command(host, cmd, data);
if (!ret && !host->use_busy)
ret = bcm2835_finish_command(host);
}
/* Wait for completion of busy signal or data transfer */
while (host->use_busy || host->data)
bcm2835_irq_poll(host);
return ret;
}
static int bcm2835_set_ios(struct udevice *dev)
{
struct bcm2835_host *host = dev_get_priv(dev);
struct mmc *mmc = mmc_get_mmc_dev(dev);
if (!mmc->clock || mmc->clock != host->clock) {
bcm2835_set_clock(host, mmc->clock);
host->clock = mmc->clock;
}
/* set bus width */
host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
if (mmc->bus_width == 4)
host->hcfg |= SDHCFG_WIDE_EXT_BUS;
host->hcfg |= SDHCFG_WIDE_INT_BUS;
/* Disable clever clock switching, to cope with fast core clocks */
host->hcfg |= SDHCFG_SLOW_CARD;
writel(host->hcfg, host->ioaddr + SDHCFG);
return 0;
}
static void bcm2835_add_host(struct bcm2835_host *host)
{
struct mmc_config *cfg = &host->plat->cfg;
cfg->f_max = host->max_clk;
cfg->f_min = host->max_clk / SDCDIV_MAX_CDIV;
cfg->b_max = 65535;
dev_dbg(dev, "f_max %d, f_min %d\n",
cfg->f_max, cfg->f_min);
/* host controller capabilities */
cfg->host_caps = MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HS_52MHz;
/* report supported voltage ranges */
cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
/* Set interrupt enables */
host->hcfg = SDHCFG_BUSY_IRPT_EN;
bcm2835_reset_internal(host);
}
static int bcm2835_probe(struct udevice *dev)
{
struct bcm2835_plat *plat = dev_get_platdata(dev);
struct bcm2835_host *host = dev_get_priv(dev);
struct mmc *mmc = mmc_get_mmc_dev(dev);
struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
host->dev = dev;
host->mmc = mmc;
host->plat = plat;
upriv->mmc = &plat->mmc;
plat->cfg.name = dev->name;
host->phys_addr = devfdt_get_addr(dev);
if (host->phys_addr == FDT_ADDR_T_NONE)
return -EINVAL;
host->ioaddr = devm_ioremap(dev, host->phys_addr, SZ_256);
if (!host->ioaddr)
return -ENOMEM;
host->max_clk = bcm2835_get_mmc_clock(BCM2835_MBOX_CLOCK_ID_CORE);
bcm2835_add_host(host);
dev_dbg(dev, "%s -> OK\n", __func__);
return 0;
}
static const struct udevice_id bcm2835_match[] = {
{ .compatible = "brcm,bcm2835-sdhost" },
{ }
};
static const struct dm_mmc_ops bcm2835_ops = {
.send_cmd = bcm2835_send_cmd,
.set_ios = bcm2835_set_ios,
};
static int bcm2835_bind(struct udevice *dev)
{
struct bcm2835_plat *plat = dev_get_platdata(dev);
return mmc_bind(dev, &plat->mmc, &plat->cfg);
}
U_BOOT_DRIVER(bcm2835_sdhost) = {
.name = "bcm2835-sdhost",
.id = UCLASS_MMC,
.of_match = bcm2835_match,
.bind = bcm2835_bind,
.probe = bcm2835_probe,
.priv_auto_alloc_size = sizeof(struct bcm2835_host),
.platdata_auto_alloc_size = sizeof(struct bcm2835_plat),
.ops = &bcm2835_ops,
};
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