From 6892fbdf9bec8441ecc797710370cab79838fa8f Mon Sep 17 00:00:00 2001
From: Roman Li <roman.li@amd.com>
Date: Tue, 14 Jan 2020 13:56:08 -0500
Subject: drm/amd/display: Fix psr static frames calculation
Git-commit: 7aa62404dfdefd759e6a5f8923a0b0704729295f
Patch-mainline: v5.6-rc2
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
[Why]
Driver crash with psr feature enabled due to divide-by-zero error.
This is a regression after rework to calculate static screen frame
number entry time.
[How]
Correct order of operations to avoid divide-by-zero.
Signed-off-by: Roman Li <roman.li@amd.com>
Reviewed-by: Zhan Liu <Zhan.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 279541517a99..63e8a12a74bc 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -8408,7 +8408,6 @@ bool amdgpu_dm_psr_enable(struct dc_stream_state *stream)
/* Calculate number of static frames before generating interrupt to
* enter PSR.
*/
- unsigned int frame_time_microsec = 1000000 / vsync_rate_hz;
// Init fail safe of 2 frames static
unsigned int num_frames_static = 2;
@@ -8423,8 +8422,10 @@ bool amdgpu_dm_psr_enable(struct dc_stream_state *stream)
* Calculate number of frames such that at least 30 ms of time has
* passed.
*/
- if (vsync_rate_hz != 0)
+ if (vsync_rate_hz != 0) {
+ unsigned int frame_time_microsec = 1000000 / vsync_rate_hz;
num_frames_static = (30000 / frame_time_microsec) + 1;
+ }
params.triggers.cursor_update = true;
params.triggers.overlay_update = true;
--
2.28.0