mmc: stm32_sdmmc2: avoid infinite while loop

Avoid unlimited while loop by adding a timeout. The timeout is
calculated based on a minimal throughput of 256 KB/s.
The timeout is set at least to 2 seconds.

Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>

diff --git a/drivers/mmc/stm32_sdmmc2.c b/drivers/mmc/stm32_sdmmc2.c
index 9483fb5..122690a 100644 (file)
--- a/drivers/mmc/stm32_sdmmc2.c
+++ b/drivers/mmc/stm32_sdmmc2.c
@@ -385,15 +385,29 @@ static int stm32_sdmmc2_end_data(struct udevice *dev,
        u32 mask = SDMMC_STA_DCRCFAIL | SDMMC_STA_DTIMEOUT |
                   SDMMC_STA_IDMATE | SDMMC_STA_DATAEND;
        u32 status;
+       unsigned long timeout_msecs = ctx->data_length >> 8;
+       unsigned long start_timeout;
+
+       /* At least, a timeout of 2 seconds is set */
+       if (timeout_msecs < 2000)
+               timeout_msecs = 2000;
 
        if (data->flags & MMC_DATA_READ)
                mask |= SDMMC_STA_RXOVERR;
        else
                mask |= SDMMC_STA_TXUNDERR;
 
+       start_timeout = get_timer(0);
        status = readl(plat->base + SDMMC_STA);
-       while (!(status & mask))
+       while (!(status & mask)) {
+               if (get_timer(start_timeout) > timeout_msecs) {
+                       ctx->dpsm_abort = true;
+                       return -ETIMEDOUT;
+               }
+
+               schedule();
                status = readl(plat->base + SDMMC_STA);
+       }
 
        /*
         * Need invalidate the dcache again to avoid any