I'd like to ask for your opinion about the following problem:
TRATS # saveenv Saving Environment to MMC... Writing to MMC(0)... Controller never released inhibit bit(s). Controller never released inhibit bit(s). Controller never released inhibit bit(s). ... failed
The same is for e.g. ext4.
The provided patch seems to solve the problem, but I DO NOT think that increasing delay is an acceptable solution to any problem.
From a brief checking I can say that it happens when we are doing
consecutive MMC operations (i.e. many reads), and the 10ms timeout might be too short when eMMC firmware is forced to do some internal time consuming operations (e.g. flash blocks management, wear leveling). In this situation, the SDHCI_CMD_INHIBIT bit is set, which means that SDHCI controller didn't received response from eMMC.
One proposition would be to define the per device/per memory chip specific timeouts, to replace those defined at ./drivers/mmc/sdhci.c file.
I also assume, that timeouts cannot be removed, since we must detect if user pulls out a SD card or transmission has been broken.
I'm also wondering if we can tune the sdhci code to improve cooperation with eMMC devices (despite of the fact that this is NOT really needed at u-boot :-) ).
Signed-off-by: Lukasz Majewski l.majewski@samsung.com Cc: Jaehoon Chung jh80.chung@samsung.com Cc: Andy Fleming afleming@gmail.com --- drivers/mmc/sdhci.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index b9cbe34..0fd1337 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -137,8 +137,8 @@ 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; + /* Wait max 100 ms */ + timeout = 100;
sdhci_writel(host, SDHCI_INT_ALL_MASK, SDHCI_INT_STATUS); mask = SDHCI_CMD_INHIBIT | SDHCI_DATA_INHIBIT;