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 <kishon@ti.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 45 insertions, 7 deletions

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index b229354e5b88..1c828e0e9905 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);
 
@@ -1198,13 +1234,6 @@ void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
 		mdelay(1);
 	}
 
-	timeout = jiffies;
-	if (!cmd->data && cmd->busy_timeout > 9000)
-		timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
-	else
-		timeout += 10 * HZ;
-	sdhci_mod_timer(host, cmd->mrq, timeout);
-
 	host->cmd = cmd;
 	if (sdhci_data_line_cmd(cmd)) {
 		WARN_ON(host->data_cmd);
@@ -1244,6 +1273,15 @@ void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
 	    cmd->opcode == MMC_SEND_TUNING_BLOCK_HS200)
 		flags |= SDHCI_CMD_DATA;
 
+	timeout = jiffies;
+	if (host->data_timeout)
+		timeout += nsecs_to_jiffies(host->data_timeout);
+	else if (!cmd->data && cmd->busy_timeout > 9000)
+		timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
+	else
+		timeout += 10 * HZ;
+	sdhci_mod_timer(host, cmd->mrq, timeout);
+
 	sdhci_writew(host, SDHCI_MAKE_CMD(cmd->opcode, flags), SDHCI_COMMAND);
 }
 EXPORT_SYMBOL_GPL(sdhci_send_command);