From: Jordan Crouse Date: Thu, 27 Jul 2017 16:42:32 +0000 (-0600) Subject: drm/msm: Turn off hardware clock gating before reading A5XX registers X-Git-Tag: v4.13-rc5~17^2~6^2~5 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=a23cb3b52fec73b22671bac65356d8c55bf37706;p=linux.git drm/msm: Turn off hardware clock gating before reading A5XX registers 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 Signed-off-by: Rob Clark --- diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c index c1f8c20414f1..33763b005b7b 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