Hi Martin, On 14/07/2018 21:37, Martin Blumenstingl wrote: > S905W SoC is another SoC from the GXL family. It is a cost-reduced > version of the S905X SoC. The following differences are known: > - S905W supports HDMI resolutions up to 4k@30fps (while S905X support > resolutions up to 4k@60fps) > - the built-in video decoders of S905W decode up to 4k@30fps (while > S905X supports decoding up to 4k@60fps) > - CPU speed on S905W is limited to 1.2GHz (compared to 1.5GHz on S905X, > this is handled in the SCPI firmware) > - the DRAM interface on S905W is limited to 16-bit (GXL supports both, > 16-bit and 32-bit) > > Notes based on Amlogic's GPL kernel sources: > - the P281 is a development board from Amlogic which uses the S905W SoC. > Amlogic's GPL kernel sources indicate that it uses the same PCB layout > as the "P231" board (and simply replaces the S905D from the original > P231 board with a S905W SoC). > - it is assumed that the S905W SoC is pin-compatible with the S905X SoC > since Amlogic's GPL kernel sources use the same driver for both SoCs. > - gxl_p281_1g.dts contains a comment which mentions that "max gp pll for > gpu is 650M, temporarily disabled". However, it seems to boot fine > with 744MHz (as used on GXBB and the other GXL SoCs). > > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > --- > Documentation/devicetree/bindings/arm/amlogic.txt | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/Documentation/devicetree/bindings/arm/amlogic.txt b/Documentation/devicetree/bindings/arm/amlogic.txt > index 849834cb1766..8178da8742c3 100644 > --- a/Documentation/devicetree/bindings/arm/amlogic.txt > +++ b/Documentation/devicetree/bindings/arm/amlogic.txt > @@ -45,6 +45,10 @@ Boards with the Amlogic Meson GXL S805X SoC shall have the following properties: > Required root node property: > compatible: "amlogic,s805x", "amlogic,meson-gxl"; > > +Boards with the Amlogic Meson GXL S905W SoC shall have the following properties: > + Required root node property: > + compatible: "amlogic,s905w", "amlogic,meson-gxl"; > + > Boards with the Amlogic Meson GXM S912 SoC shall have the following properties: > Required root node property: > compatible: "amlogic,s912", "amlogic,meson-gxm"; > @@ -85,6 +89,8 @@ Board compatible values (alphabetically, grouped by SoC): > > - "amlogic,p241" (Meson gxl s805x) > > + - "amlogic,p281" (Meson gxl s905w) > + > - "amlogic,q200" (Meson gxm s912) > - "amlogic,q201" (Meson gxm s912) > - "khadas,vim2" (Meson gxm s912) > Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
