From ede2822864c3145859372f4ad1b82f4c98584128 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Thu, 30 Jan 2020 12:06:45 +0000 Subject: [PATCH] mmc: fsl_esdhc: actually enable cache snooping on mpc830x The reference manuals for MPC8308 and MPC8309 both say that the esdhcctl aka DMA Control Register "is implemented as SDHCCR" in the System configuration registers. Unfortunately, that doesn't mean that the registers are just mirrors of each other - any write to esdhcctl is simply ignored. So to actually enable cache snooping, we unfortunately have to add a little ifdeffery. There is, naturally, no description of the bit fields of esdhcctl in the MPC8309 manual, but comparing the description of esdhcctl from the LS1021A reference manual to the description of the sdhccr in MPC8309, one also finds that the fields are bit-reversed, so the bit to set is 0x02000000 rather than 0x00000040 - this is also what board_mmc_init() uses in the two gdsys/mpc8308/ boards. Signed-off-by: Rasmus Villemoes Reviewed-by: Yangbo Lu --- drivers/mmc/fsl_esdhc.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index ab40019..386781d 100644 --- a/drivers/mmc/fsl_esdhc.c +++ b/drivers/mmc/fsl_esdhc.c @@ -578,6 +578,18 @@ static int esdhc_set_ios_common(struct fsl_esdhc_priv *priv, struct mmc *mmc) return 0; } +static void esdhc_enable_cache_snooping(struct fsl_esdhc *regs) +{ +#ifdef CONFIG_ARCH_MPC830X + immap_t *immr = (immap_t *)CONFIG_SYS_IMMR; + sysconf83xx_t *sysconf = &immr->sysconf; + + setbits_be32(&sysconf->sdhccr, 0x02000000); +#else + esdhc_write32(®s->esdhcctl, 0x00000040); +#endif +} + static int esdhc_init_common(struct fsl_esdhc_priv *priv, struct mmc *mmc) { struct fsl_esdhc *regs = priv->esdhc_regs; @@ -593,8 +605,7 @@ static int esdhc_init_common(struct fsl_esdhc_priv *priv, struct mmc *mmc) return -ETIMEDOUT; } - /* Enable cache snooping */ - esdhc_write32(®s->esdhcctl, 0x00000040); + esdhc_enable_cache_snooping(regs); esdhc_setbits32(®s->sysctl, SYSCTL_HCKEN | SYSCTL_IPGEN); -- 2.7.4