[U-Boot] [PATCH v2] mmc: fsl_esdhc: Avoid infinite loop in esdhc_send_cmd_common()
Fabio Estevam
festevam at gmail.com
Mon Nov 19 12:31:53 UTC 2018
The following hang is observed on a Hummingboard 2 MicroSOM
i2eX iMX6D - rev 1.3 with no eMMC populated on board:
U-Boot SPL 2018.11+gf6206f8587 (Nov 16 2018 - 00:56:34 +0000)
Trying to boot from MMC1
U-Boot 2018.11+gf6206f8587 (Nov 16 2018 - 00:56:34 +0000)
CPU: Freescale i.MX6D rev1.5 996 MHz (running at 792 MHz)
CPU: Extended Commercial temperature grade (-20C to 105C) at 33C
Reset cause: POR
Board: MX6 HummingBoard2
DRAM: 1 GiB
MMC: FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... *** Warning - bad CRC, using default environment
No panel detected: default to HDMI
Display: HDMI (1024x768)
In: serial
Out: serial
Err: serial
---> hangs
which is caused by the following infinite loop inside esdhc_send_cmd_common()
while (!(esdhc_read32(®s->irqstat) & flags))
;
Instead of looping forever, provide an exit path so that a timeout
error can be propagated in the case irqstat does not report
any interrupts, which may happen when no eMMC is populated on
board.
Reported-by: Ricardo Salveti <rsalveti at rsalveti.net>
Signed-off-by: Fabio Estevam <festevam at gmail.com>
---
Changes since v1:
- Jump to the label out on error path (Baruch).
drivers/mmc/fsl_esdhc.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c
index 3cdfa7f..b8d0b00 100644
--- a/drivers/mmc/fsl_esdhc.c
+++ b/drivers/mmc/fsl_esdhc.c
@@ -396,6 +396,7 @@ static int esdhc_send_cmd_common(struct fsl_esdhc_priv *priv, struct mmc *mmc,
uint irqstat;
u32 flags = IRQSTAT_CC | IRQSTAT_CTOE;
struct fsl_esdhc *regs = priv->esdhc_regs;
+ unsigned long start;
#ifdef CONFIG_SYS_FSL_ERRATUM_ESDHC111
if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
@@ -453,8 +454,13 @@ static int esdhc_send_cmd_common(struct fsl_esdhc_priv *priv, struct mmc *mmc,
flags = IRQSTAT_BRR;
/* Wait for the command to complete */
- while (!(esdhc_read32(®s->irqstat) & flags))
- ;
+ start = get_timer(0);
+ while (!(esdhc_read32(®s->irqstat) & flags)) {
+ if (get_timer(start) > 1000) {
+ err = -ETIMEDOUT;
+ goto out;
+ }
+ }
irqstat = esdhc_read32(®s->irqstat);
--
2.7.4
More information about the U-Boot
mailing list