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| author | Philipp Tomsich <philipp.tomsich@theobroma-systems.com> | 2018-11-30 20:58:58 +0300 |
|---|---|---|
| committer | Philipp Tomsich <philipp.tomsich@theobroma-systems.com> | 2018-11-30 23:56:44 +0300 |
| commit | 765246a18c9e9971632327488097b63d60a1943e (patch) | |
| tree | a299266657de8a48cdc2cf1936d46f23c02fe58a /include/dt-bindings | |
| parent | ae66a0e1a2bace085b1aeff6e0fc1bb112c45ede (diff) | |
| download | u-boot-765246a18c9e9971632327488097b63d60a1943e.tar.xz | |
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 'include/dt-bindings')
0 files changed, 0 insertions, 0 deletions