[PATCH] drm/amdgpu: reset VI ASIC on MacBookPro15,1

[Andre Eikmeyer <dev@deq.rocks>]

After S3, reloading amdgpu on MacBookPro15,1 systems with a Radeon Pro
555X or 560X fails while loading the SMU firmware. The existing SMC
register check does not request a reset because the registers do not
reliably reflect the stale SMU state on these machines.

Frederick Morlock found that forcing a VI ASIC reset allows the driver to
initialize again. This patch limits his workaround to the exact PCI
device, Apple subsystem device and revision combinations used by these
two GPUs, leaving other VI hardware unchanged.

Suggested-by: Frederick Morlock <me@freddy.us>
Signed-off-by: Andre Eikmeyer <dev@deq.rocks>
---
 drivers/gpu/drm/amd/amdgpu/vi.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/vi.c b/drivers/gpu/drm/amd/amdgpu/vi.c
index a256320b92f3..320c43143e5d 100644
--- a/drivers/gpu/drm/amd/amdgpu/vi.c
+++ b/drivers/gpu/drm/amd/amdgpu/vi.c
@@ -1407,10 +1407,30 @@ static uint64_t vi_get_pcie_replay_count(struct amdgpu_device *adev)
 	return (nak_r + nak_g);
 }
 
+struct vi_reset_quirk {
+	u16 device;
+	u16 subsystem_vendor;
+	u16 subsystem_device;
+	u8 revision;
+};
+
+static const struct vi_reset_quirk vi_reset_quirks[] = {
+	{ 0x67ef, PCI_VENDOR_ID_APPLE, 0x0190, 0xe3 }, /* Radeon Pro 555X */
+	{ 0x67ef, PCI_VENDOR_ID_APPLE, 0x018f, 0xc2 }, /* Radeon Pro 560X */
+};
+
 static bool vi_need_reset_on_init(struct amdgpu_device *adev)
 {
+	unsigned int i;
 	u32 clock_cntl, pc;
 
+	for (i = 0; i < ARRAY_SIZE(vi_reset_quirks); i++)
+		if (adev->pdev->device == vi_reset_quirks[i].device &&
+		    adev->pdev->subsystem_vendor == vi_reset_quirks[i].subsystem_vendor &&
+		    adev->pdev->subsystem_device == vi_reset_quirks[i].subsystem_device &&
+		    adev->pdev->revision == vi_reset_quirks[i].revision)
+			return true;
+
 	if (adev->flags & AMD_IS_APU)
 		return false;
 
-- 
2.55.0