From 95e277d00f8c7d9ea1836335c03ed0a15c9ad638 Mon Sep 17 00:00:00 2001
From: Roman Li <Roman.Li@amd.com>
Date: Wed, 25 May 2022 17:20:21 -0400
Subject: drm/amdgpu: fix aper_base for APU
Git-commit: ae969b62e7a1e17affae24b815b217b9b87a62f4
Patch-mainline: v5.19-rc2
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

[Why]
Wrong fb offset results in dmub f/w errors and white screen.
[drm:dc_dmub_srv_wait_idle [amdgpu]] *ERROR* Error waiting for DMUB idle: status=3

[How]
Read aper_base from mmhub because GC is off by default

v2: use BAR for passthrough (Alex)

Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
index a0c0b7d9f444..7f4b480ae66e 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
@@ -638,6 +638,12 @@ static int gmc_v11_0_mc_init(struct amdgpu_device *adev)
 	adev->gmc.aper_base = pci_resource_start(adev->pdev, 0);
 	adev->gmc.aper_size = pci_resource_len(adev->pdev, 0);
 
+#ifdef CONFIG_X86_64
+	if ((adev->flags & AMD_IS_APU) && !amdgpu_passthrough(adev)) {
+		adev->gmc.aper_base = adev->mmhub.funcs->get_mc_fb_offset(adev);
+		adev->gmc.aper_size = adev->gmc.real_vram_size;
+	}
+#endif
 	/* In case the PCI BAR is larger than the actual amount of vram */
 	adev->gmc.visible_vram_size = adev->gmc.aper_size;
 	if (adev->gmc.visible_vram_size > adev->gmc.real_vram_size)
-- 
2.38.1