On A5XX GPU hardware clock gating needs to be turned off before reading certain GPU registers via AHB. Turn off HWCG before calling adreno_show() to safely dump all the registers without a system hang.
Signed-off-by: Jordan Crouse jcrouse@codeaurora.org --- drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c index c1f8c20..33763b0 100644 --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c @@ -995,7 +995,14 @@ static void a5xx_show(struct msm_gpu *gpu, struct seq_file *m) { seq_printf(m, "status: %08x\n", gpu_read(gpu, REG_A5XX_RBBM_STATUS)); + + /* + * Temporarily disable hardware clock gating before going into + * adreno_show to avoid issues while reading the registers + */ + a5xx_set_hwcg(gpu, false); adreno_show(gpu, m); + a5xx_set_hwcg(gpu, true); } #endif