From 56b34bc617f64ce34b34cebc7cbde7a8e4c1002f Mon Sep 17 00:00:00 2001
From: Przemyslaw Marczak
Date: Tue, 8 Oct 2013 18:12:09 +0200
Subject: mmc: sdhci: Avoid commands errors by simple timeout adaptation.
Old command timeout value was too small and it caused I/O errors which
led to uncompleted read/write/erase operations and filesystem errors.
Timeout adaptation fixes this issue.
Changes in sdhci_send_command() function:
- change timeout variable to static
- increase default command timeout to 100 ms
- add definition of max command timeout value,
which can be redefined in each board config file
- wait for card ready state for max defined time
if it doesn't exceed defined maximum or return COMM_ERR
Once successfully increased timeout value will be used in next function
call. This fix was tested on Goni, Trats, Trats2 boards by testing UMS
on MMC storage.
Changes v2:
- move global variable cmd_timeout into function sdhci_send_command()
- change condition "==" to ">=" when comparing time with timeout
- print information about timeout increasing and card busy timeout
Signed-off-by: Przemyslaw Marczak
Cc: Pantelis Antoniou
---
drivers/mmc/sdhci.c | 35 ++++++++++++++++++++++++++++-------
1 file changed, 28 insertions(+), 7 deletions(-)
(limited to 'drivers/mmc')
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index dfb2eee..46ae9cb 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -109,6 +109,19 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data,
return 0;
}
+/*
+ * No command will be sent by driver if card is busy, so driver must wait
+ * for card ready state.
+ * Every time when card is busy after timeout then (last) timeout value will be
+ * increased twice but only if it doesn't exceed global defined maximum.
+ * Each function call will use last timeout value. Max timeout can be redefined
+ * in board config file.
+ */
+#ifndef CONFIG_SDHCI_CMD_MAX_TIMEOUT
+#define CONFIG_SDHCI_CMD_MAX_TIMEOUT 3200
+#endif
+#define CONFIG_SDHCI_CMD_DEFAULT_TIMEOUT 100
+
int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
struct mmc_data *data)
{
@@ -117,11 +130,12 @@ int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
int ret = 0;
int trans_bytes = 0, is_aligned = 1;
u32 mask, flags, mode;
- unsigned int timeout, start_addr = 0;
+ unsigned int time = 0, start_addr = 0;
unsigned int retry = 10000;
+ int mmc_dev = mmc->block_dev.dev;
- /* Wait max 10 ms */
- timeout = 10;
+ /* Timeout unit - ms */
+ static unsigned int cmd_timeout = CONFIG_SDHCI_CMD_DEFAULT_TIMEOUT;
sdhci_writel(host, SDHCI_INT_ALL_MASK, SDHCI_INT_STATUS);
mask = SDHCI_CMD_INHIBIT | SDHCI_DATA_INHIBIT;
@@ -132,11 +146,18 @@ int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
mask &= ~SDHCI_DATA_INHIBIT;
while (sdhci_readl(host, SDHCI_PRESENT_STATE) & mask) {
- if (timeout == 0) {
- printf("Controller never released inhibit bit(s).\n");
- return COMM_ERR;
+ if (time >= cmd_timeout) {
+ printf("MMC: %d busy ", mmc_dev);
+ if (2 * cmd_timeout <= CONFIG_SDHCI_CMD_MAX_TIMEOUT) {
+ cmd_timeout += cmd_timeout;
+ printf("timeout increasing to: %u ms.\n",
+ cmd_timeout);
+ } else {
+ puts("timeout.\n");
+ return COMM_ERR;
+ }
}
- timeout--;
+ time++;
udelay(1000);
}
--
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