[PATCH 03/17] drm/msm: Turn off hardware clock gating before reading A5XX registers

[Jordan Crouse]

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 at 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
 
-- 
1.9.1