[J/OEM-5.14] [PATCH 2/3] drm/amdgpu: don't use BACO for reset in S3

[Kai-Heng Feng]

From: Alex Deucher <alexander.deucher at amd.com>

BugLink: https://bugs.launchpad.net/bugs/1968475

Seems to cause a reboots or hangs on some systems.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1924
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1953
Fixes: daf8de0874ab5b ("drm/amdgpu: always reset the asic in suspend (v2)")
Reviewed-by: Lijo Lazar <lijo.lazar at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Cc: stable at vger.kernel.org
(cherry picked from commit ebc002e3ee78409c42156e62e4e27ad1d09c5a75)
Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
---
 drivers/gpu/drm/amd/pm/amdgpu_dpm.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
index 08362d506534b..a68496b3f9296 100644
--- a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
+++ b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
@@ -1045,6 +1045,17 @@ bool amdgpu_dpm_is_baco_supported(struct amdgpu_device *adev)
 
 	if (!pp_funcs || !pp_funcs->get_asic_baco_capability)
 		return false;
+	/* Don't use baco for reset in S3.
+	 * This is a workaround for some platforms
+	 * where entering BACO during suspend
+	 * seems to cause reboots or hangs.
+	 * This might be related to the fact that BACO controls
+	 * power to the whole GPU including devices like audio and USB.
+	 * Powering down/up everything may adversely affect these other
+	 * devices.  Needs more investigation.
+	 */
+	if (adev->in_s3)
+		return false;
 
 	if (pp_funcs->get_asic_baco_capability(pp_handle, &baco_cap))
 		return false;
-- 
2.34.1