From b75a52b0dda353aeefb4830a320589a363f49579 Mon Sep 17 00:00:00 2001 From: Shawn Lin Date: Thu, 2 Feb 2023 08:35:16 +0800 Subject: [PATCH] mmc: sdhci-of-dwcmshc: Update DLL and pre-change delay for rockchip platform For Rockchip platform, DLL bypass bit and start bit need to be set if DLL is not locked. And adjust pre-change delay to 0x3 for better signal test result. Signed-off-by: Shawn Lin Link: https://lore.kernel.org/r/1675298118-64243-2-git-send-email-shawn.lin@rock-chips.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-of-dwcmshc.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/drivers/mmc/host/sdhci-of-dwcmshc.c +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c @@ -48,6 +48,7 @@ #define DWCMSHC_EMMC_DLL_RXCLK_SRCSEL 29 #define DWCMSHC_EMMC_DLL_START_POINT 16 #define DWCMSHC_EMMC_DLL_INC 8 +#define DWCMSHC_EMMC_DLL_BYPASS BIT(24) #define DWCMSHC_EMMC_DLL_DLYENA BIT(27) #define DLL_TXCLK_TAPNUM_DEFAULT 0x10 #define DLL_TXCLK_TAPNUM_90_DEGREES 0xA @@ -60,6 +61,7 @@ #define DLL_RXCLK_NO_INVERTER 1 #define DLL_RXCLK_INVERTER 0 #define DLL_CMDOUT_TAPNUM_90_DEGREES 0x8 +#define DLL_RXCLK_ORI_GATE BIT(31) #define DLL_CMDOUT_TAPNUM_FROM_SW BIT(24) #define DLL_CMDOUT_SRC_CLK_NEG BIT(28) #define DLL_CMDOUT_EN_SRC_CLK_NEG BIT(29) @@ -234,9 +236,12 @@ static void dwcmshc_rk3568_set_clock(str sdhci_writel(host, extra, reg); if (clock <= 52000000) { - /* Disable DLL and reset both of sample and drive clock */ - sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_CTRL); - sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_RXCLK); + /* + * Disable DLL and reset both of sample and drive clock. + * The bypass bit and start bit need to be set if DLL is not locked. + */ + sdhci_writel(host, DWCMSHC_EMMC_DLL_BYPASS | DWCMSHC_EMMC_DLL_START, DWCMSHC_EMMC_DLL_CTRL); + sdhci_writel(host, DLL_RXCLK_ORI_GATE, DWCMSHC_EMMC_DLL_RXCLK); sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_TXCLK); sdhci_writel(host, 0, DECMSHC_EMMC_DLL_CMDOUT); /* @@ -279,7 +284,7 @@ static void dwcmshc_rk3568_set_clock(str } extra = 0x1 << 16 | /* tune clock stop en */ - 0x2 << 17 | /* pre-change delay */ + 0x3 << 17 | /* pre-change delay */ 0x3 << 19; /* post-change delay */ sdhci_writel(host, extra, dwc_priv->vendor_specific_area1 + DWCMSHC_EMMC_ATCTRL);