Re: [RFC PATCH 0/3] ARm64: amlogic: Introduce common GX family dtsi

From: Kevin Hilman
Date: Wed Aug 31 2016 - 15:33:24 EST

Neil Armstrong <narmstrong@xxxxxxxxxxxx> writes:

> On 08/29/2016 10:15 PM, Andreas FÃrber wrote:
>> Am 29.08.2016 um 21:50 schrieb Carlo Caione:
>>> On 29/08/16 20:38, Andreas FÃrber wrote:
>>>> Am 29.08.2016 um 10:01 schrieb Carlo Caione:
>>>>> On Mon, Aug 29, 2016 at 9:56 AM, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>>>>> Neil Armstrong (3):
>>>>>> ARM64: dts: amlogic: Add Meson GX Family common dtsi
>>>>>> ARM64: dts: amlogic: Switch Meson GXL dtsi to use common GX dtsi
>>>>>> ARM64: dts: amlogic: Switch Meson GXBB dtsi to use common GX dtsi
>>>> Adding an unused .dtsi duplicating GXBB makes me uneasy.
>>> S905x (GXL) is different from S905 (GXBB), it's unused now but in the
>>> future we can expect something different in the two DTSI.
>> Guess I need to be --verbose. ;)
>> I meant: After patch 1/3 there is a gx-common.dtsi that duplicates
>> contents of gxbb.dtsi and is not yet #include'd anywhere, i.e., unused.
>>>> Any chance we can simplify this to at most two steps?
>>>> 1) Move code from gxbb to gx (1/3 + 3/3)
>>>> 2) Add gxl using gx ("Add basic support for Amlogic S905X" + 2/3)
>>> fine by me.
> I can merge carlo's GXL support into this patchet.
>>>> Alternatively:
>>>> 1) "Add basic support for Amlogic S905X"
>>>> 2) Factor out common bits (1/3 + 2/3 + 3/3)
>>> how is this different from this patchset?
>> I'm suggesting we do "atomic" move operations, not copy and then remove.
>> The difference between my two suggestions is how many and which changes
>> we squash - I do appreciate that it's easy for review as is but what I
>> have in mind is that either we should get this refactoring applied asap
>> (#1 1)) and rebase all pending patches on it, or we may need to rebase
>> the refactoring onto any pending MMC, SDIO, etc. patches, which I feel
>> is safer to do in one big patch (#2 2)) than split over multiple ones.
>> It really depends on the merge order and roadmap you guys have in mind.
> I'm not very convinced about the utility the reduce commits... having a dtsi alone won't arm anyone.
> Nevertheless, I will squash the two commits.
>>>> As for bike-shedding, is there a GX family as well or could we drop
>>>> -common? .dtsi is always something common - compare Exynos or i.MX.
>>>> Since there are meson8b and meson8 I was anticipating that after gxbb
>>>> would come gx, not gxl.
>>> AFAIK we have:
>>> - GXBB
>>> - GXL
>>> - GXM
>>> - GXTVBB
>>>> Do you know what the L in GXL is for? Should we consider renaming gxbb
>>>> to gxb, and then also insert -s905 as suggested by Kevin, for symmetry?
>>> Yes, that make sense.
> As Amlogic told us, we have at least two families :
> - GXBB with the S905
> - GXL with the S905D and S905X
> The GXL and GXBB families will share a lot, except the clocks tree, pinctrl registers, USB IP versions and at least ethernet PHY handling.
> But the two GXL SoCs will still share a lot, maybe everything, we are not sure for now.
> In the Amlogic SDK kernel, we can see more families :
> - GXM seems to be the S912 since it has two clusters of 4xA53, but looks identical to GXL for pinctrl and clocks
> - GXTVBB looking at the Amlogic SDK it could be a GXBB variant with a different GPU (t83x instead of mali450), pinctrl and clocks
> In their SDK, there is a single GXL pinctrl and clock driver for GXL and GXM.
> Taking in account all the boards, families and SoCs, we should have the following:
> meson-gx-common.dtsi
> âââ meson-gxbb-s905.dtsi
> â âââ meson-gxbb-s905-odroidc2.dts
> â âââ meson-gxbb-s905-p20x.dtsi
> â âââ meson-gxbb-s905-p200.dts
> â âââ meson-gxbb-s905-p201.dts
> âââ meson-gxl.dtsi
> â âââ meson-gxl-s905d.dtsi
> â â âââ meson-gxl-s905d-p23x.dts
> â â âââ meson-gxl-s905d-p230.dts
> â â âââ meson-gxl-s905d-p231.dts
> â âââ meson-gxl-s905x.dtsi
> â âââ meson-gxl-s905x-p212.dts
> âââ meson-gxm-s912.dtsi
> âââ meson-gxm-s912-q20x.dtsi
> âââ meson-gxm-s912-q200.dts
> âââ meson-gxm-s912-q201.dts
> But since GXBB will only be S905, we can drop the S905 naming and keep what is already upstream,
> then GXM won't happen until a certain time so I plan to push the following :
> meson-gx-common.dtsi

nit: drop the -common, as suggested by Andreas since it's kidna
redundant since it's a .dtsi.

> âââ meson-gxbb.dtsi
> â âââ meson-gxbb-odroidc2.dts
> â âââ meson-gxbb-p20x.dtsi
> â âââ meson-gxbb-p200.dts
> â âââ meson-gxbb-p201.dts
> âââ meson-gxl.dtsi
> âââ meson-gxl-s905d.dtsi
> â âââ meson-gxl-s905d-p23x.dts
> â âââ meson-gxl-s905d-p230.dts
> â âââ meson-gxl-s905d-p231.dts
> âââ meson-gxl-s905x.dtsi
> âââ meson-gxl-s905x-p212.dts
> But the meson-gxl-s905d.dtsi, meson-gxl-s905x.dtsi and meson-gxl.dtsi will be empty until we push the pinctrl, clock, ethernet PHY and USB nodes for them.

Looks good to me.