| Message ID | 20210323140019.14388-1-heiko.thiery@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] arm64: dts: imx8mq-kontron-pitx-imx8m: pass phy reset delays | expand |
On Tue, Mar 23, 2021 at 03:00:21PM +0100, Heiko Thiery wrote: > The TI DP83867 PHY datasheet says: > T1: Post RESET stabilization time == 195us > T3: Hardware configuration pins transition to output drivers == 64us > T4: RESET pulse width == 1us > > So with a little overhead set 'reset-assert-us' to 10us (T4) and > 'reset-deassert-us' to 280us (T1+T3). > > Without these reset delays the board will hang during startup when > bootargs has ip=dhcp set. > > Fixes: 1dc7f3d79a1a ("arm64: dts: fsl: add support for Kontron pitx-imx8m board") > Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com> > --- > v2: > - add desciption what issue will be fixed > - add Fixes tag My branch is not a stable one, so I just squashed it into the original commit. Shawn
diff --git a/arch/arm64/boot/dts/freescale/imx8mq-kontron-pitx-imx8m.dts b/arch/arm64/boot/dts/freescale/imx8mq-kontron-pitx-imx8m.dts index 91a9ceb10305..f593e4ff62e1 100644 --- a/arch/arm64/boot/dts/freescale/imx8mq-kontron-pitx-imx8m.dts +++ b/arch/arm64/boot/dts/freescale/imx8mq-kontron-pitx-imx8m.dts @@ -90,6 +90,8 @@ ethphy0: ethernet-phy@0 { ti,tx-internal-delay = <DP83867_RGMIIDCTL_2_75_NS>; ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>; reset-gpios = <&gpio1 11 GPIO_ACTIVE_LOW>; + reset-assert-us = <10>; + reset-deassert-us = <280>; }; }; };
The TI DP83867 PHY datasheet says: T1: Post RESET stabilization time == 195us T3: Hardware configuration pins transition to output drivers == 64us T4: RESET pulse width == 1us So with a little overhead set 'reset-assert-us' to 10us (T4) and 'reset-deassert-us' to 280us (T1+T3). Without these reset delays the board will hang during startup when bootargs has ip=dhcp set. Fixes: 1dc7f3d79a1a ("arm64: dts: fsl: add support for Kontron pitx-imx8m board") Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com> --- v2: - add desciption what issue will be fixed - add Fixes tag arch/arm64/boot/dts/freescale/imx8mq-kontron-pitx-imx8m.dts | 2 ++ 1 file changed, 2 insertions(+)