[PATCHv3] drm/amdgpu: disable ASPM on Intel Alder Lake based systems

From: Richard Gong
Date: Tue Apr 12 2022 - 10:59:46 EST


Active State Power Management (ASPM) feature is enabled since kernel 5.14.
There are some AMD GFX cards (such as WX3200 and RX640) that won't work
with ASPM-enabled Intel Alder Lake based systems. Using these GFX cards as
video/display output, Intel Alder Lake based systems will hang during
suspend/resume.

The issue was initially reported on one system (Dell Precision 3660 with
BIOS version 0.14.81), but was later confirmed to affect at least 4 Alder
Lake based systems.

Add extra check to disable ASPM on Intel Alder Lake based systems.

Fixes: 0064b0ce85bb ("drm/amd/pm: enable ASPM by default")
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1885
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Richard Gong <richard.gong@xxxxxxx>
---
v3: s/intel_core_asom_chk/aspm_support_quirk_check
correct build error with W=1 option
v2: correct commit description
move the check from chip family to problematic platform
---
drivers/gpu/drm/amd/amdgpu/vi.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/vi.c b/drivers/gpu/drm/amd/amdgpu/vi.c
index 039b90cdc3bc..b0b6353b48b9 100644
--- a/drivers/gpu/drm/amd/amdgpu/vi.c
+++ b/drivers/gpu/drm/amd/amdgpu/vi.c
@@ -81,6 +81,10 @@
#include "mxgpu_vi.h"
#include "amdgpu_dm.h"

+#if IS_ENABLED(CONFIG_X86_64)
+#include <asm/intel-family.h>
+#endif
+
#define ixPCIE_LC_L1_PM_SUBSTATE 0x100100C6
#define PCIE_LC_L1_PM_SUBSTATE__LC_L1_SUBSTATES_OVERRIDE_EN_MASK 0x00000001L
#define PCIE_LC_L1_PM_SUBSTATE__LC_PCI_PM_L1_2_OVERRIDE_MASK 0x00000002L
@@ -1134,13 +1138,24 @@ static void vi_enable_aspm(struct amdgpu_device *adev)
WREG32_PCIE(ixPCIE_LC_CNTL, data);
}

+static bool aspm_support_quirk_check(void)
+{
+ if (IS_ENABLED(CONFIG_X86_64)) {
+ struct cpuinfo_x86 *c = &cpu_data(0);
+
+ return (c->x86 == 6 && c->x86_model != INTEL_FAM6_ALDERLAKE);
+ }
+
+ return true;
+}
+
static void vi_program_aspm(struct amdgpu_device *adev)
{
u32 data, data1, orig;
bool bL1SS = false;
bool bClkReqSupport = true;

- if (!amdgpu_device_should_use_aspm(adev))
+ if (!amdgpu_device_should_use_aspm(adev) || !aspm_support_quirk_check())
return;

if (adev->flags & AMD_IS_APU ||
--
2.25.1