[U-Boot] [PATCH] mmc:sdhci: Fix card ready status timeout.

[Przemyslaw Marczak]

According to JEDEC eMMC specification, after data transfer
(multiple or single block) host must wait for card ready
status. This is done by waiting for command and data lines
to be at idle state after transfer. JEDEC does not specify
maximum timeout.

Before this change max timeout was 10 ms but in case of UMS
- when system does multiple read/write operations on random
card blocks - timeout causes I/O errors.
The timeout has been increased to 200ms after data transfer.
For other transfers it stays unchanged. Default values are
now defined with "if defined" directive so it can be redefined
at board config if needed.

Tested on Goni and Trats.

Signed-off-by: Przemyslaw Marczak <p.marczak at samsung.com>
Cc: Pantelis Antoniou <panto at antoniou-consulting.com>
---
 drivers/mmc/sdhci.c |   20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 4261991..35bdb37 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -110,6 +110,20 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data,
 	return 0;
 }
 
+#if !defined(SDHCI_DATA_CMD_TIMEOUT)
+#define SDHCI_DATA_CMD_TIMEOUT		10
+#endif
+#if !defined(SDHCI_STATUS_CMD_TIMEOUT)
+#define SDHCI_STATUS_CMD_TIMEOUT	200
+#endif
+/*
+ * For some commands this function is called with NULL mmc_data
+ * pointer. One of those is CMD13 - send card status.
+ * After read/write data transfer or block erase commands - host sends
+ * CMD13 and is waiting for card ready status with some timeout.
+ * According to some internal cards operations after those commands
+ * this time must be increased.
+ */
 int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
 		       struct mmc_data *data)
 {
@@ -121,8 +135,10 @@ int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
 	unsigned int timeout, start_addr = 0;
 	unsigned int retry = 10000;
 
-	/* Wait max 10 ms */
-	timeout = 10;
+	if (data)
+		timeout = SDHCI_DATA_CMD_TIMEOUT; /* ms */
+	else
+		timeout = SDHCI_STATUS_CMD_TIMEOUT;
 
 	sdhci_writel(host, SDHCI_INT_ALL_MASK, SDHCI_INT_STATUS);
 	mask = SDHCI_CMD_INHIBIT | SDHCI_DATA_INHIBIT;
-- 
1.7.9.5