On Thu, 23 Feb 2023 at 03:47, Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> wrote: > > Implement gpu_busy based on the downstream msm-3.4 code [1]. This > allows us to use devfreq on this old old old hardware! > > [1] https://github.com/LineageOS/android_kernel_sony_apq8064/blob/lineage-16.0/drivers/gpu/msm/adreno_a2xx.c#L1975 > > Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Small nit below > --- > drivers/gpu/drm/msm/adreno/a2xx_gpu.c | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/drivers/gpu/drm/msm/adreno/a2xx_gpu.c b/drivers/gpu/drm/msm/adreno/a2xx_gpu.c > index c67089a7ebc1..6f9876b37db5 100644 > --- a/drivers/gpu/drm/msm/adreno/a2xx_gpu.c > +++ b/drivers/gpu/drm/msm/adreno/a2xx_gpu.c > @@ -481,6 +481,29 @@ a2xx_create_address_space(struct msm_gpu *gpu, struct platform_device *pdev) > return aspace; > } > > +/* While the precise size of this field is unknown, it holds at least these three values.. */ > +static u64 a2xx_gpu_busy(struct msm_gpu *gpu, unsigned long *out_sample_rate) > +{ > + u64 busy_cycles; > + > + /* Freeze the counter */ > + gpu_write(gpu, REG_A2XX_CP_PERFMON_CNTL, PERF_STATE_FREEZE); > + > + busy_cycles = gpu_read64(gpu, REG_A2XX_RBBM_PERFCOUNTER1_LO); > + > + /* Reset the counter */ > + gpu_write(gpu, REG_A2XX_CP_PERFMON_CNTL, PERF_STATE_RESET); > + > + /* Re-enable the performance monitors */ > + gpu_rmw(gpu, REG_A2XX_RBBM_PM_OVERRIDE2, BIT(6), BIT(6)); It's DEBUG_PERF_SCLK_PM_OVERRIDE See https://github.com/genesi/linux-legacy/blob/master/drivers/mxc/amd-gpu/include/reg/yamato/10/yamato_mask.h#L4428 > + gpu_write(gpu, REG_A2XX_RBBM_PERFCOUNTER1_SELECT, 1); > + gpu_write(gpu, REG_A2XX_CP_PERFMON_CNTL, PERF_STATE_ENABLE); > + > + *out_sample_rate = clk_get_rate(gpu->core_clk); > + > + return busy_cycles; > +} > + > static u32 a2xx_get_rptr(struct msm_gpu *gpu, struct msm_ringbuffer *ring) > { > ring->memptrs->rptr = gpu_read(gpu, REG_AXXX_CP_RB_RPTR); > @@ -502,6 +525,7 @@ static const struct adreno_gpu_funcs funcs = { > #if defined(CONFIG_DEBUG_FS) || defined(CONFIG_DEV_COREDUMP) > .show = adreno_show, > #endif > + .gpu_busy = a2xx_gpu_busy, > .gpu_state_get = a2xx_gpu_state_get, > .gpu_state_put = adreno_gpu_state_put, > .create_address_space = a2xx_create_address_space, > > -- > 2.39.2 > -- With best wishes Dmitry