[PATCH v2 0/3] GPU DVFS for Meson GXBB/GXL/GXM/G12A/G12B/SM1

Martin Blumenstingl martin.blumenstingl at googlemail.com
Sun Jul 19 13:32:10 EDT 2020


Now that we have GPU DVFS support in lima [0] (in Linux 5.7) and
panfrost we can make it work on Amlogic SoCs.

I decided to remove code duplication for the Mali-450 GPU on GXBB and
GXL so it will be easier to maintain this. This refactoring is part of
patch #1. Patches #2 (GXM) and #3 (G12A, G12B, SM1) are straight
forward; it replaces the hardcoded clock settings with the the GPU OPP
table.

I used the userspace devfreq governor to cycle through all available
GPU frequency settings on GXL, GXM and G12A (which covers all relevant
GPU driver and clock driver combinations). I have taken the GPU OPP
tables from Amlogic's 4.9 vendor kernel and the voltage settings
(opp-microvolt property) from the public dataseheets for all SoCs.


Changes since v1 at [1]:
- removed the clock patches from this series as they are already
  applied (in Linux 5.8)
- rebased on top of Neil's recent patch "arm64: dts: meson-gxl-s805x:
  reduce initial Mali450 core frequency"
- adapted patch #1 after Neil's GXL S805X patch to keep the 744MHz OPP
  disabled on that package
- added a comment about GP0_PLL (as to why it's needed) to all patch
  descriptions
- removed RFC prefix


[0] https://cgit.freedesktop.org/drm-misc/commit/?id=1996970773a323533e1cc1b6b97f00a95d675f32
[1] https://patchwork.kernel.org/cover/11466399/


Martin Blumenstingl (3):
  arm64: dts: amlogic: meson-gx: add the Mali-450 OPP table and use DVFS
  arm64: dts: amlogic: meson-gxm: add the Mali OPP table and use DVFS
  arm64: dts: amlogic: meson-g12: add the Mali OPP table and use DVFS

 .../boot/dts/amlogic/meson-g12-common.dtsi    | 49 ++++++++++-----
 .../boot/dts/amlogic/meson-gx-mali450.dtsi    | 61 +++++++++++++++++++
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi   | 51 ++++------------
 .../boot/dts/amlogic/meson-gxl-mali.dtsi      | 46 +++-----------
 .../boot/dts/amlogic/meson-gxl-s805x.dtsi     | 17 +++---
 arch/arm64/boot/dts/amlogic/meson-gxm.dtsi    | 45 +++++++++-----
 6 files changed, 153 insertions(+), 116 deletions(-)
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gx-mali450.dtsi

-- 
2.27.0




More information about the linux-arm-kernel mailing list