From 7294863a6f01248d72b61d38478978d638641bee Mon Sep 17 00:00:00 2001
From: Mario Limonciello <mario.limonciello@amd.com>
Date: Tue, 1 Feb 2022 10:26:33 -0600
Subject: drm/amd: Check if ASPM is enabled from PCIe subsystem
Git-commit: 7294863a6f01248d72b61d38478978d638641bee
Patch-mainline: v5.17-rc6
References: git-fixes
Alt-commit: cba07cce39ace4c719e63b0410a53480aee6aaee

commit 0064b0ce85bb ("drm/amd/pm: enable ASPM by default") enabled ASPM
by default but a variety of hardware configurations it turns out that this
caused a regression.

* PPC64LE hardware does not support ASPM at a hardware level.
  CONFIG_PCIEASPM is often disabled on these architectures.
* Some dGPUs on ALD platforms don't work with ASPM enabled and PCIe subsystem
  disables it

Check with the PCIe subsystem to see that ASPM has been enabled
or not.

Fixes: 0064b0ce85bb ("drm/amd/pm: enable ASPM by default")
Link: https://wiki.raptorcs.com/w/images/a/ad/P9_PHB_version1.0_27July2018_pub.pdf
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1723
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1739
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1885
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1907
Tested-by: koba.ko@canonical.com
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -1260,6 +1260,9 @@
 	bool is_fw_fb;
 	resource_size_t base, size;
 
+	if (amdgpu_aspm == -1 && !pcie_aspm_enabled(pdev))
+		amdgpu_aspm = 0;
+
 	if (!amdgpu_virtual_display &&
 	    amdgpu_device_asic_has_dc_support(flags & AMD_ASIC_MASK))
 		supports_atomic = true;