diff options
author | Christoph Muellner <christoph.muellner@theobroma-systems.com> | 2019-03-22 12:34:53 +0100 |
---|---|---|
committer | Heiko Stuebner <heiko@sntech.de> | 2019-03-27 13:45:27 +0100 |
commit | b4e1728232d64b8040dae9b5405cf2db7ebd4e8b (patch) | |
tree | c9962ce3cb5160170621c03d183bfb98af4e8049 | |
parent | fb8b7460c9950001b923da446f393c452d0ccf09 (diff) |
arm64: dts: rockchip: Decrease emmc-phy's drive impedance on rk3399-puma
The RK3399-Q7 (Puma) requires 33 Ohm drive strength to ensure signal
integrity at HS-400 (200MHz clock, DDR signalling).
A repeated EMC testing run validates that this increase does not
negatively impact EMC compliance (emissions have ample distance to
the regulatory limits).
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>
Tested-by: Klaus Goger <klaus.goger@theobroma-systems.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
-rw-r--r-- | arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi index 0130b9f98c9d..4f75bb6b2f14 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi @@ -146,6 +146,7 @@ &emmc_phy { status = "okay"; + drive-impedance-ohm = <33>; }; &gmac { |