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From 465931e70881476a210d44705102ef8b6ee6cdb0 Mon Sep 17 00:00:00 2001
From: Robin Murphy <robin.murphy@arm.com>
Date: Thu, 18 Jun 2020 18:56:29 +0100
Subject: [PATCH] clk: rockchip: Revert "fix wrong mmc sample phase shift for rk3328"
Git-commit: 465931e70881476a210d44705102ef8b6ee6cdb0
Patch-mainline: v5.9-rc1
References: git-fixes

This reverts commit 82f4b67f018c88a7cc9337f0067ed3d6ec352648.

According to a subsequent revert in the vendor kernel, the original
change was based on unclear documentation and was in fact incorrect.

Emprically, my board's HS200 eMMC at 200MHZ apparently gets lucky with a
phase where this had no impact, but limiting max-frequency to 150MHz to
match the nominal capability of the I/O pins made it virtually unusable,
constantly throwing errors and retuning. With this revert, it starts
behaving perfectly at 150MHz too.

Fixes: 82f4b67f018c ("clk: rockchip: fix wrong mmc sample phase shift for rk3328")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://lore.kernel.org/r/c80eb52e34c03f817586b6b7912fbd4e31be9079.1589475794.git.robin.murphy@arm.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/clk/rockchip/clk-rk3328.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/rockchip/clk-rk3328.c b/drivers/clk/rockchip/clk-rk3328.c
index c186a1985bf4..2429b7c2a8b3 100644
--- a/drivers/clk/rockchip/clk-rk3328.c
+++ b/drivers/clk/rockchip/clk-rk3328.c
@@ -808,22 +808,22 @@ static struct rockchip_clk_branch rk3328_clk_branches[] __initdata = {
 	MMC(SCLK_SDMMC_DRV, "sdmmc_drv", "clk_sdmmc",
 	    RK3328_SDMMC_CON0, 1),
 	MMC(SCLK_SDMMC_SAMPLE, "sdmmc_sample", "clk_sdmmc",
-	    RK3328_SDMMC_CON1, 0),
+	    RK3328_SDMMC_CON1, 1),
 
 	MMC(SCLK_SDIO_DRV, "sdio_drv", "clk_sdio",
 	    RK3328_SDIO_CON0, 1),
 	MMC(SCLK_SDIO_SAMPLE, "sdio_sample", "clk_sdio",
-	    RK3328_SDIO_CON1, 0),
+	    RK3328_SDIO_CON1, 1),
 
 	MMC(SCLK_EMMC_DRV, "emmc_drv", "clk_emmc",
 	    RK3328_EMMC_CON0, 1),
 	MMC(SCLK_EMMC_SAMPLE, "emmc_sample", "clk_emmc",
-	    RK3328_EMMC_CON1, 0),
+	    RK3328_EMMC_CON1, 1),
 
 	MMC(SCLK_SDMMC_EXT_DRV, "sdmmc_ext_drv", "clk_sdmmc_ext",
 	    RK3328_SDMMC_EXT_CON0, 1),
 	MMC(SCLK_SDMMC_EXT_SAMPLE, "sdmmc_ext_sample", "clk_sdmmc_ext",
-	    RK3328_SDMMC_EXT_CON1, 0),
+	    RK3328_SDMMC_EXT_CON1, 1),
 };
 
 static const char *const rk3328_critical_clocks[] __initconst = {
-- 
2.16.4