Re: [PATCH 0/5] Meson (32-bit): add support for the Mali GPU

[Kevin Hilman <khilman@baylibre.com>]

Neil Armstrong <narmstrong@baylibre.com> writes:

> On 08/12/2018 18:12, Martin Blumenstingl wrote:
>> This series adds support for the Mali-450 GPU on Meson8 and Meson8b.
>> Meson6 uses a Mali-400 GPU but since we don't have a clock driver (and
>> I don't have a device for testing) Meson6 is left out in this series.
>> 
>> Meson8 uses a Mali-450 MP6 with six pixel processors. Meson8b (as
>> cost-reduced SoC) uses a Mali-450 MP2 with two pixel processors.
>> I tested both using the open source lima driver and a patched mesa
>> from the lima project as well. Since we don't have display support
>> on the 32-bit SoCs I used off-screen rendering as described in [0].
>> The result is (for example): [1]
>> 
>> The bootloader (at least on my boards) leaves the Mali clock disabled
>> by default. The board crashes when trying to access the Mali registers
>> with the "core" clock disabled.
>> Thus this series also implements the required clock driver changes. The
>> Mali clock tree on Meson8b and Meson8m2 is almost identical to the one
>> on GXBB (see the description of patch #3 for more details). Only Meson8
>> is slightly different as it doesn't have a glitch-free mux. Patch #2
>> prepares the meson8b clock driver so we can have different clocks per
>> SoC.
>> 
>> Dependencies:
>> - the .dts changes depend on my other series "ARM: dts: meson: add the
>>   APB/APB2 busses" from [2]
>> - the .dts changes from this series have no compile-time dependency on
>>   the clock driver changes because CLKID_MALI was defined in the
>>   dt-bindings since the first version of the clock driver (but it was
>>   not used until now).
>> - the .dts changes from this series have a runtime dependency on the
>>   clock driver changes (also from this series) if you have a kernel
>>   patched with the lima driver (without the lima driver there's no
>>   runtime dependency)
>> 
>> Other notes:
>> By default the GPU runs off the XTAL clock (24MHz). The lima driver
>> currently does not update the GPU clock rate. Different frequencies
>> have to be requested by adding the following properties to the Mali
>> GPU node (to run it at 510MHz for example):
>>   assigned-clocks = <&clkc CLKID_MALI>;
>>   assigned-clock-rates = <510000000>;
>> 
>> 
>> [0] https://gitlab.freedesktop.org/lima/web/wikis/home
>> [1] https://abload.de/img/dump0myic0.png
>> [2] https://patchwork.kernel.org/cover/10719445/
>> 
>> 
>> Martin Blumenstingl (5):
>>   dt-bindings: gpu: mali-utgard: add Amlogic Meson8 and Meson8b
>>     compatible
>>   clk: meson: meson8b: use a separate clock table for Meson8
>>   clk: meson: meson8b: add the GPU clock tree
>>   ARM: dts: meson8: add the Mali-450 MP6 GPU
>>   ARM: dts: meson8b: add the Mali-450 MP2 GPU
>> 
>>  .../bindings/gpu/arm,mali-utgard.txt          |   6 +
>>  arch/arm/boot/dts/meson8.dtsi                 |  58 +++
>>  arch/arm/boot/dts/meson8b.dtsi                |  46 +++
>>  drivers/clk/meson/meson8b.c                   | 349 +++++++++++++++++-
>>  drivers/clk/meson/meson8b.h                   |   9 +-
>>  5 files changed, 461 insertions(+), 7 deletions(-)
>> 
>
> Applied patches 2 & 3 to next/drivers for Linux 5.1
>
> Kevin, have fun with the other patches !

Fun was had.

Patches 1, 4, 5 queued for v5.1 (branch: v5.1/dt)

Kevin