openwrt/target/linux/brcm2708/patches-4.1/0092-bcm2835-sdhost-Further-improve-overclock-back-off.patch
John Crispin bf28fb50bf brcm2708: update 4.1 patches
As usual, this patches were taken (and rebased) from
https://github.com/raspberrypi/linux/commits/rpi-4.1.y

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

SVN-Revision: 47258
2015-10-26 09:01:05 +00:00

293 lines
8.8 KiB
Diff

From 8509eb475ed00c7d581cf05866a27fa48c4c007c Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Thu, 25 Jun 2015 08:47:09 +0100
Subject: [PATCH 092/203] bcm2835-sdhost: Further improve overclock back-off
---
drivers/mmc/host/bcm2835-sdhost.c | 144 +++++++++++++++++++++-----------------
1 file changed, 78 insertions(+), 66 deletions(-)
--- a/drivers/mmc/host/bcm2835-sdhost.c
+++ b/drivers/mmc/host/bcm2835-sdhost.c
@@ -161,8 +161,6 @@ struct bcm2835_host {
unsigned int use_busy:1; /* Wait for busy interrupt */
- unsigned int reduce_overclock:1; /* ...at the next opportunity */
-
unsigned int debug:1; /* Enable debug output */
u32 thread_isr;
@@ -466,36 +464,25 @@ static void bcm2835_sdhost_dma_complete(
spin_unlock_irqrestore(&host->lock, flags);
}
-static bool data_transfer_wait(struct bcm2835_host *host, const char *caller)
+static bool data_transfer_wait(struct bcm2835_host *host)
{
unsigned long timeout = 1000000;
- u32 hsts;
while (timeout)
{
- hsts = bcm2835_sdhost_read(host, SDHSTS);
- if (hsts & (SDHSTS_TRANSFER_ERROR_MASK |
- SDHSTS_DATA_FLAG)) {
- bcm2835_sdhost_write(host, SDHSTS_TRANSFER_ERROR_MASK,
- SDHSTS);
+ u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+ if (sdhsts & SDHSTS_DATA_FLAG) {
+ bcm2835_sdhost_write(host, SDHSTS_DATA_FLAG, SDHSTS);
break;
}
timeout--;
}
-
- if (hsts & (SDHSTS_CRC16_ERROR |
- SDHSTS_CRC7_ERROR |
- SDHSTS_FIFO_ERROR)) {
- pr_err("%s: data error in %s - HSTS %x\n",
- mmc_hostname(host->mmc), caller, hsts);
- host->data->error = -EILSEQ;
- return false;
- } else if ((timeout == 0) ||
- (hsts & (SDHSTS_CMD_TIME_OUT |
- SDHSTS_REW_TIME_OUT))) {
- pr_err("%s: timeout in %s - HSTS %x\n",
- mmc_hostname(host->mmc), caller, hsts);
- host->data->error = -ETIMEDOUT;
- return false;
+ if (timeout == 0) {
+ pr_err("%s: Data %s timeout\n",
+ mmc_hostname(host->mmc),
+ (host->data->flags & MMC_DATA_READ) ? "read" : "write");
+ bcm2835_sdhost_dumpregs(host);
+ host->data->error = -ETIMEDOUT;
+ return false;
}
return true;
}
@@ -523,7 +510,7 @@ static void bcm2835_sdhost_read_block_pi
buf = (u32 *)host->sg_miter.addr;
while (len) {
- if (!data_transfer_wait(host, "read_block_pio"))
+ if (!data_transfer_wait(host))
break;
*(buf++) = bcm2835_sdhost_read(host, SDDATA);
@@ -562,7 +549,7 @@ static void bcm2835_sdhost_write_block_p
buf = host->sg_miter.addr;
while (len) {
- if (!data_transfer_wait(host, "write_block_pio"))
+ if (!data_transfer_wait(host))
break;
bcm2835_sdhost_write(host, *(buf++), SDDATA);
@@ -581,13 +568,33 @@ static void bcm2835_sdhost_write_block_p
static void bcm2835_sdhost_transfer_pio(struct bcm2835_host *host)
{
+ u32 sdhsts;
+ bool is_read;
BUG_ON(!host->data);
- if (host->data->flags & MMC_DATA_READ) {
+ is_read = (host->data->flags & MMC_DATA_READ) != 0;
+ if (is_read)
bcm2835_sdhost_read_block_pio(host);
- } else {
+ else
bcm2835_sdhost_write_block_pio(host);
+ sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+ if (sdhsts & (SDHSTS_CRC16_ERROR |
+ SDHSTS_CRC7_ERROR |
+ SDHSTS_FIFO_ERROR)) {
+ pr_err("%s: %s transfer error - HSTS %x\n",
+ mmc_hostname(host->mmc),
+ is_read ? "read" : "write",
+ sdhsts);
+ host->data->error = -EILSEQ;
+ } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
+ SDHSTS_REW_TIME_OUT))) {
+ pr_err("%s: %s timeout error - HSTS %x\n",
+ mmc_hostname(host->mmc),
+ is_read ? "read" : "write",
+ sdhsts);
+ host->data->error = -ETIMEDOUT;
+ } else if (!is_read && !host->data->error) {
/* Start a timer in case a transfer error occurs because
there is no error interrupt */
mod_timer(&host->pio_timer, jiffies + host->pio_timeout);
@@ -701,8 +708,9 @@ static void bcm2835_sdhost_prepare_data(
void bcm2835_sdhost_send_command(struct bcm2835_host *host, struct mmc_command *cmd)
{
- u32 sdcmd;
+ u32 sdcmd, sdhsts;
unsigned long timeout;
+ int delay;
WARN_ON(host->cmd);
@@ -719,8 +727,8 @@ void bcm2835_sdhost_send_command(struct
mmc_hostname(host->mmc),
cmd->opcode, cmd->arg, cmd->flags);
- /* Wait max 10 ms */
- timeout = 1000;
+ /* Wait max 100 ms */
+ timeout = 10000;
while (bcm2835_sdhost_read(host, SDCMD) & SDCMD_NEW_FLAG) {
if (timeout == 0) {
@@ -735,8 +743,9 @@ void bcm2835_sdhost_send_command(struct
udelay(10);
}
- if ((1000-timeout)/100 > 1 && (1000-timeout)/100 > host->max_delay) {
- host->max_delay = (1000-timeout)/100;
+ delay = (10000 - timeout)/100;
+ if (delay > host->max_delay) {
+ host->max_delay = delay;
pr_warning("%s: controller hung for %d ms\n",
mmc_hostname(host->mmc),
host->max_delay);
@@ -751,6 +760,11 @@ void bcm2835_sdhost_send_command(struct
host->cmd = cmd;
+ /* Clear any error flags */
+ sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+ if (sdhsts & SDHSTS_ERROR_MASK)
+ bcm2835_sdhost_write(host, sdhsts, SDHSTS);
+
bcm2835_sdhost_prepare_data(host, cmd);
bcm2835_sdhost_write(host, cmd->arg, SDARG);
@@ -876,7 +890,7 @@ static void bcm2835_sdhost_transfer_comp
static void bcm2835_sdhost_finish_command(struct bcm2835_host *host)
{
u32 sdcmd;
- int timeout = 1000;
+ unsigned long timeout;
#ifdef DEBUG
struct timeval before, after;
int timediff = 0;
@@ -889,6 +903,8 @@ static void bcm2835_sdhost_finish_comman
#ifdef DEBUG
do_gettimeofday(&before);
#endif
+ /* Wait max 100 ms */
+ timeout = 10000;
for (sdcmd = bcm2835_sdhost_read(host, SDCMD);
(sdcmd & SDCMD_NEW_FLAG) && timeout;
timeout--) {
@@ -1049,9 +1065,9 @@ static void bcm2835_sdhost_pio_timeout(u
spin_lock_irqsave(&host->lock, flags);
if (host->data) {
- u32 hsts = bcm2835_sdhost_read(host, SDHSTS);
+ u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS);
- if (hsts & SDHSTS_REW_TIME_OUT) {
+ if (sdhsts & SDHSTS_REW_TIME_OUT) {
pr_err("%s: transfer timeout\n",
mmc_hostname(host->mmc));
if (host->debug)
@@ -1380,19 +1396,10 @@ void bcm2835_sdhost_set_clock(struct bcm
if (host->debug)
pr_info("%s: set_clock(%d)\n", mmc_hostname(host->mmc), clock);
- if ((clock == 0) && host->reduce_overclock) {
- /* This is a reset following data corruption - reduce any
- overclock */
- host->reduce_overclock = 0;
- if (host->overclock_50 > 50) {
- pr_warn("%s: reducing overclock due to errors\n",
- mmc_hostname(host->mmc));
- host->overclock_50--;
- }
- }
-
- if (host->overclock_50 && (clock == 50*MHZ))
+ if ((host->overclock_50 > 50) &&
+ (clock == 50*MHZ)) {
clock = host->overclock_50 * MHZ + (MHZ - 1);
+ }
/* The SDCDIV register has 11 bits, and holds (div - 2).
But in data mode the max is 50MHz wihout a minimum, and only the
@@ -1450,11 +1457,12 @@ void bcm2835_sdhost_set_clock(struct bcm
host->overclock = clock;
}
}
- else if ((clock == 50 * MHZ) && host->overclock)
+ else if (host->overclock)
{
- pr_warn("%s: cancelling overclock\n",
- mmc_hostname(host->mmc));
host->overclock = 0;
+ if (clock == 50 * MHZ)
+ pr_warn("%s: cancelling overclock\n",
+ mmc_hostname(host->mmc));
}
host->cdiv = div;
@@ -1492,6 +1500,14 @@ static void bcm2835_sdhost_request(struc
cmd->opcode, cmd->arg, cmd->flags);
}
+ /* Reset the error statuses in case this is a retry */
+ if (mrq->cmd)
+ mrq->cmd->error = 0;
+ if (mrq->data)
+ mrq->data->error = 0;
+ if (mrq->stop)
+ mrq->stop->error = 0;
+
if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
pr_err("%s: unsupported block size (%d bytes)\n",
mmc_hostname(mmc), mrq->data->blksz);
@@ -1613,21 +1629,16 @@ static void bcm2835_sdhost_tasklet_finis
/* Drop the overclock after any data corruption, or after any
error overclocked */
- if (mrq->data && (mrq->data->error == -EILSEQ))
- host->reduce_overclock = 1;
- else if (host->overclock) {
- /* Convert timeout errors while overclocked to data errors,
- because the system recovers better. */
- if (mrq->cmd && mrq->cmd->error) {
- host->reduce_overclock = 1;
- if (mrq->cmd->error == -ETIMEDOUT)
- mrq->cmd->error = -EILSEQ;
- }
-
- if (mrq->data && mrq->data->error) {
- host->reduce_overclock = 1;
- if (mrq->data->error == -ETIMEDOUT)
- mrq->data->error = -EILSEQ;
+ if (host->overclock) {
+ if ((mrq->cmd && mrq->cmd->error) ||
+ (mrq->data && mrq->data->error) ||
+ (mrq->stop && mrq->stop->error)) {
+ host->overclock_50--;
+ pr_warn("%s: reducing overclock due to errors\n",
+ mmc_hostname(host->mmc));
+ bcm2835_sdhost_set_clock(host,50*MHZ);
+ mrq->cmd->error = -EILSEQ;
+ mrq->cmd->retries = 1;
}
}
@@ -1769,6 +1780,7 @@ static int bcm2835_sdhost_probe(struct p
host = mmc_priv(mmc);
host->mmc = mmc;
host->pio_timeout = msecs_to_jiffies(500);
+ host->max_delay = 1; /* Warn if over 1ms */
spin_lock_init(&host->lock);
iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);