diff options
| author | Philipp Tomsich <philipp.tomsich@theobroma-systems.com> | 2018-11-30 18:58:58 +0100 |
|---|---|---|
| committer | Philipp Tomsich <philipp.tomsich@theobroma-systems.com> | 2018-11-30 21:56:44 +0100 |
| commit | 765246a18c9e9971632327488097b63d60a1943e (patch) | |
| tree | a299266657de8a48cdc2cf1936d46f23c02fe58a /arch/arm/dts/rk3399-puma.dtsi | |
| parent | ae66a0e1a2bace085b1aeff6e0fc1bb112c45ede (diff) | |
rockchip: rk3399-puma: reduce sd card max-frequency to 40MHz
Some SanDisk Ultra cards trigger intermittent errors on detection
resulting in an -EOPNOTSUPP, when running at 50MHz.
Waveform analysis suggest that the level shifters that are used on the
RK3399-Q7 module (for voltage translation between the on-module
voltages and the 3.3V required on the card-edge) don't handle clock
rates at or above 48MHz properly. This change reduces the maximum
frequency on the external SD-interface to 40MHz (for a safety margin
of 20%).
Reported-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Diffstat (limited to 'arch/arm/dts/rk3399-puma.dtsi')
| -rw-r--r-- | arch/arm/dts/rk3399-puma.dtsi | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm/dts/rk3399-puma.dtsi b/arch/arm/dts/rk3399-puma.dtsi index 6e7e1e3528..11ffcb7177 100644 --- a/arch/arm/dts/rk3399-puma.dtsi +++ b/arch/arm/dts/rk3399-puma.dtsi @@ -503,7 +503,7 @@ &sdmmc { u-boot,dm-pre-reloc; clock-frequency = <150000000>; - clock-freq-min-max = <100000 150000000>; + max-frequency = <40000000>; supports-sd; bus-width = <4>; cap-mmc-highspeed; |