This is my attempt at adding devfreq (and cooling device) support to the lima driver.
Test results from a Meson8m2 board: TEST #1: glmark2-es2-drm --off-screen in an infinite loop while cycling through all available frequencies using the userspace governor
From : To : 182142857 318750000 425000000 510000000 637500000 time(ms) 182142857: 0 1274 1274 1273 1279 5399468 318750000: 1274 0 1274 1273 1272 5114700 425000000: 1276 1274 0 1272 1271 5122008 510000000: 1909 1273 1273 0 636 5274292 * 637500000: 640 1272 1272 1273 0 5186796 Total transition : 24834
TEST #2: glmark2-es2-drm --off-screen in an infinite loop with the simple_ondemand governor From : To : 182142857 318750000 425000000 510000000 637500000 time(ms) 182142857: 0 0 0 0 203 318328 318750000: 53 0 0 0 21 56044 425000000: 27 18 0 0 2 34172 510000000: 27 6 14 0 1 41348 * 637500000: 95 50 33 48 0 2085312
Changes since RFC v3 at [2]: - fix devfreq init error handling and allow lima_devfreq_fini to be called multiple times (thanks Qiang) - switch from atomic counter to a simple int which is only accessed under the devfreq spinlock (thanks Qiang) - union lock areas in same function (thanks Qiang) - select DEVFREQ_GOV_SIMPLE_ONDEMAND like panfrost does (thanks Qiang) - move lima_devfreq struct to lima_devfreq.h (thanks Qiang) - fix duplicate variable in lima_sched_pipe_task_done - only call dev_pm_opp_of_remove_table if dev_pm_opp_of_add_table succeeded previously - update copyright year to 2020 - rebased on top of drm-misc-next - dropped RFC status
Changes since RFC v2 at [1]: - added #cooling-cells to the dt-bindings (new patch #1) - skip devfreq initialization when the operating-points-v2 property is absent - call dev_pm_opp_set_regulators() so devfreq will actually manage the mali-supply regulator - rebased on top of drm-misc-next-2020-02-21
Changes since RFC v1 at [0]: - added lock to protect the statistics as these can be written concurrently for example when the GP and PP IRQ are firing at the same time. Thanks to Qiang Yu for the suggestion! - updated the copyright notice of lima_devfreq.c to indicate that the code is derived from panfrost_devfreq.c. Thanks to Chen-Yu Tsai for the suggestion! - I did not unify the code with panfrost yet because I don't know where to put the result. any suggestion is welcome though!
[0] https://patchwork.freedesktop.org/series/70967/ [1] https://patchwork.kernel.org/cover/11311293/ [2] https://patchwork.kernel.org/cover/11398365/
Martin Blumenstingl (2): dt-bindings: gpu: mali-utgard: Add the #cooling-cells property drm/lima: Add optional devfreq and cooling device support
.../bindings/gpu/arm,mali-utgard.yaml | 4 + drivers/gpu/drm/lima/Kconfig | 2 + drivers/gpu/drm/lima/Makefile | 3 +- drivers/gpu/drm/lima/lima_devfreq.c | 234 ++++++++++++++++++ drivers/gpu/drm/lima/lima_devfreq.h | 41 +++ drivers/gpu/drm/lima/lima_device.c | 4 + drivers/gpu/drm/lima/lima_device.h | 3 + drivers/gpu/drm/lima/lima_drv.c | 14 +- drivers/gpu/drm/lima/lima_sched.c | 7 + drivers/gpu/drm/lima/lima_sched.h | 3 + 10 files changed, 312 insertions(+), 3 deletions(-) create mode 100644 drivers/gpu/drm/lima/lima_devfreq.c create mode 100644 drivers/gpu/drm/lima/lima_devfreq.h