Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Quentin Schulz <foss+kernel@0leil.net>
To:     foss+kernel@0leil.net,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Heiko Stuebner <heiko@sntech.de>,
        Rob Herring <robh+dt@kernel.org>
Cc:     Quentin Schulz <quentin.schulz@theobroma-systems.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org,
        Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: [PATCH] arm64: dts: rockchip: lower rk3399-puma-haikou SD controller
 clock frequency
Date:   Wed, 19 Oct 2022 16:27:27 +0200
Message-Id: <20221019-upstream-puma-sd-40mhz-v1-0-754a76421518@theobroma-systems.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8BIT
Precedence: bulk

From: Quentin Schulz <quentin.schulz@theobroma-systems.com>


From: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>


CRC errors (code -84 EILSEQ) have been observed for some SanDisk

Ultra A1 cards when running at 50MHz.


Waveform analysis suggest that the level shifters that are used on the

RK3399-Q7 module for voltage translation between 3.0 and 3.3V don't

handle clock rates at or above 48MHz properly. Back off to 40MHz for

some safety margin.


Cc: stable@vger.kernel.org

Fixes: 60fd9f72ce8a ("arm64: dts: rockchip: add Haikou baseboard with RK3399-Q7 SoM")

Signed-off-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>

Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>

---

We've been carrying this patch downstream for years and completely forgot to

upstream it. This is now done.


To: Rob Herring <robh+dt@kernel.org>

To: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>

To: Heiko Stuebner <heiko@sntech.de>

Cc: devicetree@vger.kernel.org

Cc: linux-arm-kernel@lists.infradead.org

Cc: linux-rockchip@lists.infradead.org

Cc: linux-kernel@vger.kernel.org

Cc: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>

---

 arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)


diff --git a/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts b/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts

index 04c752f49be9..115c14c0a3c6 100644

--- a/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts

+++ b/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts

@@ -207,7 +207,7 @@ &sdmmc {

 	cap-sd-highspeed;

 	cd-gpios = <&gpio0 RK_PA7 GPIO_ACTIVE_LOW>;

 	disable-wp;

-	max-frequency = <150000000>;

+	max-frequency = <40000000>;

 	pinctrl-names = "default";

 	pinctrl-0 = <&sdmmc_clk &sdmmc_cmd &sdmmc_cd &sdmmc_bus4>;

 	vmmc-supply = <&vcc3v3_baseboard>;


---

base-commit: aae703b02f92bde9264366c545e87cec451de471

change-id: 20221019-upstream-puma-sd-40mhz-b5aef1c351e6


Best regards,

-- 

Quentin Schulz <quentin.schulz@theobroma-systems.com>