From: Jerry (Fangzhi) Zuo <Jerry.Zuo@amd.com>
Date: Fri, 24 Apr 2020 18:09:23 +0000 (-0400)
Subject: drm/amd/display: Check DMCU Exists Before Loading
X-Git-Tag: v5.8-rc1~194^2~11^2~40
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=17bdb4a82fe5014c8aa5b2103c80c5729744a096;p=thirdparty%2Fkernel%2Fstable.git

drm/amd/display: Check DMCU Exists Before Loading

Signed-off-by: Jerry (Fangzhi) Zuo <Jerry.Zuo@amd.com>
Reviewed-by: Hersen Wu <hersenxs.wu@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

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 26e370986c0cc..2e0b86cea879f 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1389,9 +1389,14 @@ static int dm_late_init(void *handle)
 	struct dmcu_iram_parameters params;
 	unsigned int linear_lut[16];
 	int i;
-	struct dmcu *dmcu = adev->dm.dc->res_pool->dmcu;
+	struct dmcu *dmcu = NULL;
 	bool ret = false;
 
+	if (!adev->dm.fw_dmcu)
+		return detect_mst_link_for_all_connectors(adev->ddev);
+
+	dmcu = adev->dm.dc->res_pool->dmcu;
+
 	for (i = 0; i < 16; i++)
 		linear_lut[i] = 0xFFFF * i / 15;