[PATCH] mmc: stm32_sdmmc2: avoid infinite while loop

[Christophe Kerello]

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 at foss.st.com>
---

 drivers/mmc/stm32_sdmmc2.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/stm32_sdmmc2.c b/drivers/mmc/stm32_sdmmc2.c
index 9483fb57daf..122690aef3e 100644
--- 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
-- 
2.25.1

base-commit: d1d54857dc618f8c080dbb87de5218e6c330b0d4
branch: SDMMC-avoid-infinite-loop