[PATCH] mmc: fsl_esdhc_imx: check the clock stable status after config the clock rate.

From: Haibo Chen haibo.chen@nxp.com

Currently, after config the clock rate, delay 10ms, this is quite a rough method. Check the clock stable status in the present status register is enough.

Tested-by: Ji Luo ji.luo@nxp.com Signed-off-by: Haibo Chen haibo.chen@nxp.com --- drivers/mmc/fsl_esdhc_imx.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/fsl_esdhc_imx.c b/drivers/mmc/fsl_esdhc_imx.c index 788677984b..b60623e0ce 100644 --- a/drivers/mmc/fsl_esdhc_imx.c +++ b/drivers/mmc/fsl_esdhc_imx.c @@ -631,6 +631,7 @@ static void set_sysctl(struct fsl_esdhc_priv *priv, struct mmc *mmc, uint clock) { struct fsl_esdhc *regs = priv->esdhc_regs; int div = 1; + u32 time_out = 50; #ifdef ARCH_MXC #ifdef CONFIG_MX53 /* For i.MX53 eSDHCv3, SYSCTL.SDCLKFS may not be set to 0. */ @@ -664,7 +665,14 @@ static void set_sysctl(struct fsl_esdhc_priv *priv, struct mmc *mmc, uint clock)

esdhc_clrsetbits32(&regs->sysctl, SYSCTL_CLOCK_MASK, clk);

- udelay(10000); + while (!(esdhc_read32(&regs->prsstat) & PRSSTAT_SDSTB)) { + if (time_out == 0) { + printf("fsl_esdhc_imx: Internal clock never stabilised.\n"); + break; + } + time_out--; + udelay(2); + }

#ifdef CONFIG_FSL_USDHC esdhc_setbits32(&regs->vendorspec, VENDORSPEC_PEREN | VENDORSPEC_CKEN);