From patchwork Mon Nov 19 12:31:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [U-Boot, v2] mmc: fsl_esdhc: Avoid infinite loop in esdhc_send_cmd_common() X-Patchwork-Submitter: Fabio Estevam X-Patchwork-Id: 999792 Message-Id: <1542630713-30355-1-git-send-email-festevam@gmail.com> To: jh80.chung@samsung.com Cc: baruch@tkos.co.il, u-boot@lists.denx.de Date: Mon, 19 Nov 2018 10:31:53 -0200 From: Fabio Estevam List-Id: U-Boot discussion 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 Signed-off-by: Fabio Estevam --- 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);