>From 0976d161bfb9c9a35c5176c8059c4ed9a985a0b2 Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Wed, 7 Mar 2018 18:50:16 +0530 Subject: [PATCH 3/3] mmc: sdhci: Program a relatively accurate SW timeout value sdhci has a 10 second timeout to catch devices that stop responding. In the case of quirk SDHCI_QUIRK2_DISABLE_HW_TIMEOUT, instead of programming 10 second arbitrary value, calculate the total time it would take for the entire transfer to happen and program the timeout value accordingly. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Adrian Hunter --- drivers/mmc/host/sdhci.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/mmc/host/sdhci.h | 10 ++++++++++ 2 files changed, 46 insertions(+) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 7c0683b8baba..d67ac1bf7caa 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -738,6 +738,39 @@ static unsigned int sdhci_target_timeout(struct sdhci_host *host, return target_timeout; } +static void sdhci_calc_sw_timeout(struct sdhci_host *host, + struct mmc_command *cmd) +{ + struct mmc_data *data = cmd->data; + struct mmc_host *mmc = host->mmc; + struct mmc_ios *ios = &mmc->ios; + unsigned char bus_width = 1 << ios->bus_width; + unsigned int blksz; + unsigned int freq; + u64 target_timeout; + u64 transfer_time; + + target_timeout = sdhci_target_timeout(host, cmd, data); + target_timeout *= NSEC_PER_USEC; + + if (data) { + blksz = data->blksz; + freq = host->mmc->actual_clock ? : host->clock; + transfer_time = (u64)blksz * NSEC_PER_SEC * (8 / bus_width); + do_div(transfer_time, freq); + /* multiply by '2' to account for any unknowns */ + transfer_time = transfer_time * 2; + /* calculate timeout for the entire data */ + host->data_timeout = data->blocks * target_timeout + + transfer_time; + } else { + host->data_timeout = target_timeout; + } + + if (host->data_timeout) + host->data_timeout += MMC_CMD_TRANSFER_TIME; +} + static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_command *cmd, bool *too_big) { @@ -831,6 +864,7 @@ static void sdhci_set_timeout(struct sdhci_host *host, struct mmc_command *cmd) if (too_big && host->quirks2 & SDHCI_QUIRK2_DISABLE_HW_TIMEOUT) { + sdhci_calc_sw_timeout(host, cmd); sdhci_set_data_timeout_irq(host, false); } else if (!(host->ier & SDHCI_INT_DATA_TIMEOUT)) { sdhci_set_data_timeout_irq(host, true); @@ -845,6 +879,8 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd) u8 ctrl; struct mmc_data *data = cmd->data; + host->data_timeout = 0; + if (sdhci_data_line_cmd(cmd)) sdhci_set_timeout(host, cmd); diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index f6555c0f4ad3..23966f887da6 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -332,6 +332,14 @@ struct sdhci_adma2_64_desc { /* Allow for a a command request and a data request at the same time */ #define SDHCI_MAX_MRQS 2 +/* + * 48bit command and 136 bit response in 100KHz clock could take upto 2.48ms. + * However since the start time of the command, the time between + * command and response, and the time between response and start of data is + * not known, set the command transfer time to 10ms. + */ +#define MMC_CMD_TRANSFER_TIME (10 * NSEC_PER_MSEC) /* max 10 ms */ + enum sdhci_cookie { COOKIE_UNMAPPED, COOKIE_PRE_MAPPED, /* mapped by sdhci_pre_req() */ @@ -555,6 +563,8 @@ struct sdhci_host { /* Host SDMA buffer boundary. */ u32 sdma_boundary; + u64 data_timeout; + unsigned long private[0] ____cacheline_aligned; }; -- 1.9.1