Hello Krzysztof,

On 09/30/2015 02:30 AM, Krzysztof Kozlowski wrote:

[snip]

quoted

The DTS in the vendor ChromeOS tree are called exynos5250-snow-rev{4,5}.dtb
but I decided to leave Rev4 as exynos5250-snow.dtb to avoid breaking u-boot
that has CONFIG_DEFAULT_DEVICE_TREE="exynos5250-snow" in snow_defconfig.

Also, ChromiumOS Rev4 DTS has "google,snow-rev4" in its compatible string
but was not added in mainline since Rev4 firmware fallbacks to "google,snow"
and Rev5 searches for "google,snow-rev5". That way the compatible string
could be consistent with the DTS naming and still be able to pack both Rev4
and Rev5 FDT in the same FIT image and let the firmware pick the correct FDT.

 arch/arm/boot/dts/Makefile                    |   1 +
 arch/arm/boot/dts/exynos5250-snow-common.dtsi | 684 ++++++++++++++++++++++++++
 arch/arm/boot/dts/exynos5250-snow-rev5.dts    |  47 ++
 arch/arm/boot/dts/exynos5250-snow.dts         | 666 +------------------------
 4 files changed, 733 insertions(+), 665 deletions(-)
 create mode 100644 arch/arm/boot/dts/exynos5250-snow-common.dtsi
 create mode 100644 arch/arm/boot/dts/exynos5250-snow-rev5.dts

Now the exynos5250-snow.dts means in fact Rev4... but there is no
information in DTS about it. I think adding compatible
"google,snow-rev4" makes sense:
1. For informational purposes (this could be also handled with a comment).
2. Later one could decide to switch the default meaning of "google,snow"
to Rev5 and the real compatible (rev4) will be there already.

Ok, I explained my rationale about why I did not add a "google,snow-rev4"
but I don't have a strong opinion on this so I'll add it on v2.
 

Could you add the new compatible and fix patch issues pointed by Doug?

Sure.

Best regards,
Krzysztof

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America