[PATCH 0/2] Enable internal strobe pulldown on Radxa ROCK 4 SBCs

From: Folker Schwesinger
Date: Wed Mar 27 2024 - 15:27:07 EST


Various RK3399 boards, including the ROCK Pi 4 series showed instabilities
with some eMMC modules when operating in HS400 mode [1]. Later, a missing
pull-down resistor on the eMMC strobe line was identified as the root
cause of these instabilities [2].

This series enables the internal pull-down on the eMMC PHY strobe line
for all ROCK 4 series boards as they all lack an external strobe
pull-down resistor.

Furthermore, HS400 mode is re-enabled for these boards. Previously, to
workaround the instabilities until the issue was investigated further,
HS400 mode was replaced with HS200 mode [1].

[1]: https://lore.kernel.org/all/20230705144255.115299-1-chris.obbard@xxxxxxxxxxxxx/
[2]: https://lore.kernel.org/all/20220822074139.3810-1-jensenhuang@xxxxxxxxxxxxxxx/


Folker Schwesinger (2):
arm64: dts: rockchip: Add enable-strobe-pulldown to emmc phy on ROCK
Pi 4
arm64: dts: rockchip: Add enable-strobe-pulldown to emmc phy on ROCK
4C+

arch/arm64/boot/dts/rockchip/rk3399-rock-4c-plus.dts | 4 +++-
arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi | 4 +++-
2 files changed, 6 insertions(+), 2 deletions(-)


base-commit: 4cece764965020c22cff7665b18a012006359095
--
2.44.0