[PATCH 11/11] drm/amdgpu/gfx6: Enable IP block soft reset as a GPU recovery method

["Timur Kristóf" <timur.kristof@gmail.com>]

Enable IP block soft reset as a GPU recovery method for GFX6
graphics and compute rings.

This improves current user experience on all GFX6 chips.
The current GPU recovery method is a legacy ASIC reset which
always clears the contents of VRAM, which means that a buggy
(hanging) app can crash the whole graphical session, which
is less than ideal. Also on some GPUs the ASIC reset causes
the GPU to fall off the PCIe bus so it's not desireable.

Using GFX IP block soft reset means that we can now
move on from GFX hangs on GFX6 dGPUs without crashing the
whole system.

Tested with the "hard_reset_cp_wait" test case from the
Hang Test Suite created by Natalie Vock and Konstantin Seurer.
This Vulkan testcase waits for an event that never occurs,
effectively a WAIT_REG_MEM packet that intentionally hangs.
IP block soft reset can resolve that hang and allow
the rest of the system to move on and keep functioning
without needing a full ASIC reset.

Tested on the following chips:

Tahiti (FirePro W9000, Radeon HD 7870 XT)
Cape Verde (Radeon R7 450)
Pitcairn (Radeon R9 270X)
Oland (Radeon 430)

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c
index a033da5fc307..f24129b54408 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c
@@ -3242,6 +3242,11 @@ static int gfx_v6_0_sw_init(struct amdgpu_ip_block *ip_block)
 	adev->gfx.compute_supported_reset =
 		amdgpu_get_soft_full_reset_mask(&adev->gfx.compute_ring[0]);
 
+	if (!amdgpu_sriov_vf(adev) && !adev->debug_disable_ip_block_soft_reset) {
+		adev->gfx.compute_supported_reset |= AMDGPU_RESET_TYPE_IP_BLOCK_SOFT_RESET;
+		adev->gfx.gfx_supported_reset |= AMDGPU_RESET_TYPE_IP_BLOCK_SOFT_RESET;
+	}
+
 	return r;
 }
 
-- 
2.55.0