diff options
author | Christoph Muellner <christoph.muellner@theobroma-systems.com> | 2019-02-28 16:06:40 +0100 |
---|---|---|
committer | Christoph Muellner <christoph.muellner@theobroma-systems.com> | 2019-10-02 00:39:29 +0200 |
commit | 677d2493014d43337ccacb209e4a76d240ca36a3 (patch) | |
tree | d6148ca80ce4959e25538af7b04b65b8c79e6fa4 | |
parent | 82be2f2211a0bec01f531665d5316614381c583d (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>
-rw-r--r-- | arch/arm64/boot/dts/rockchip/rk3399-puma.dts | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-puma.dts b/arch/arm64/boot/dts/rockchip/rk3399-puma.dts index ba95a94c247e..a8a5e38150f7 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dts +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dts @@ -366,6 +366,7 @@ &emmc_phy { status = "okay"; + drive-impedance-ohm = <33>; }; &gmac { |