diff options
| author | Christoph Muellner <christoph.muellner@theobroma-systems.com> | 2018-12-19 16:06:06 +0100 |
|---|---|---|
| committer | Christoph Müllner <christophm30@gmail.com> | 2019-04-07 15:15:51 +0200 |
| commit | c171b74ed5edcb2d7b98a33fe24b86c492699c3c (patch) | |
| tree | 29e40022c28dcad95610f6db302fbb52f18f6d69 | |
| parent | 4d552acf337038028f7e2f63a927afb7adf65fc1 (diff) | |
rockchip: rk3399-puma: Reduce SD card max-frequency to 40 MHz
Some combinations of SD cards and our modules show errors on detection
or later at operation (e.g. "Detected aborted journal") when run
at 50 MHz or higher.
Waveform analysis suggest that the level shifters that are used on
RK3399-Q7 module for voltage translation between 3.0 and 3.3V don't
handle clock rates at or above 48MHz properly. This change reduces
maximum frequency on the external SD-interface to 40MHz for some
safety margin.
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
| -rw-r--r-- | arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts b/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts index 8ce4a79d9360..87bd03242229 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma-haikou.dts @@ -203,7 +203,7 @@ 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>; |