From fa0223a75946ad3aec2596dac34d88f2dcca7baa Mon Sep 17 00:00:00 2001 From: Oleksandr Suvorov Date: Wed, 8 Sep 2021 21:56:43 +0300 Subject: mmc: sdhci-esdhc-imx: Add HS400 support for iMX7ULP Import HS400 support for iMX7ULP B0 from the Linux kernel: 2eaf5a533afd ("mmc: sdhci-esdhc-imx: Add HS400 support for iMX7ULP") According to IC suggest, need to clear the STROBE_DLL_CTRL_RESET before any setting of STROBE_DLL_CTRL register. USDHC has register bits(bit[27~20] of register STROBE_DLL_CTRL) for slave sel value. If this register bits value is 0, it needs 256 ref_clk cycles to update slave sel value. IC suggest to set bit[27~20] to 0x4, it only need 4 ref_clk cycle to update slave sel value. This will short the lock time of slave. i.MX7ULP B0 will need more time to lock the REF and SLV, so change to add 5us delay. Signed-off-by: Oleksandr Suvorov Reviewed-by: Fabio Estevam Reviewed-by: Jaehoon Chung Reviewed-by: Igor Opaniuk --- drivers/mmc/fsl_esdhc_imx.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'drivers/mmc') diff --git a/drivers/mmc/fsl_esdhc_imx.c b/drivers/mmc/fsl_esdhc_imx.c index 2ee53c7106..4c06361bee 100644 --- a/drivers/mmc/fsl_esdhc_imx.c +++ b/drivers/mmc/fsl_esdhc_imx.c @@ -727,17 +727,20 @@ static void esdhc_set_strobe_dll(struct mmc *mmc) if (priv->clock > ESDHC_STROBE_DLL_CLK_FREQ) { esdhc_write32(®s->strobe_dllctrl, ESDHC_STROBE_DLL_CTRL_RESET); + /* clear the reset bit on strobe dll before any setting */ + esdhc_write32(®s->strobe_dllctrl, 0); /* * enable strobe dll ctrl and adjust the delay target * for the uSDHC loopback read clock */ val = ESDHC_STROBE_DLL_CTRL_ENABLE | + ESDHC_STROBE_DLL_CTRL_SLV_UPDATE_INT_DEFAULT | (priv->strobe_dll_delay_target << ESDHC_STROBE_DLL_CTRL_SLV_DLY_TARGET_SHIFT); esdhc_write32(®s->strobe_dllctrl, val); - /* wait 1us to make sure strobe dll status register stable */ - mdelay(1); + /* wait 5us to make sure strobe dll status register stable */ + mdelay(5); val = esdhc_read32(®s->strobe_dllstat); if (!(val & ESDHC_STROBE_DLL_STS_REF_LOCK)) pr_warn("HS400 strobe DLL status REF not lock!\n"); @@ -1709,7 +1712,8 @@ static struct esdhc_soc_data usdhc_imx7d_data = { static struct esdhc_soc_data usdhc_imx7ulp_data = { .flags = ESDHC_FLAG_USDHC | ESDHC_FLAG_STD_TUNING - | ESDHC_FLAG_HAVE_CAP1 | ESDHC_FLAG_HS200, + | ESDHC_FLAG_HAVE_CAP1 | ESDHC_FLAG_HS200 + | ESDHC_FLAG_HS400, }; static struct esdhc_soc_data usdhc_imx8qm_data = { -- cgit v1.2.3