[PATCH 14/22] drm/amdgpu: change gfx9 ib test to use WB

[Monk Liu]

two reasons to switch SCRATCH reg method to WB method:

1)Because when doing IB test we don't want to involve KIQ health
status affect, and since SCRATCH register access is go through
KIQ that way GFX IB test would failed due to KIQ fail.

2)acccessing SCRATCH register cost much more time than WB method
because SCRATCH register access runs through KIQ which at least could
begin after GPU world switch back to current Guest VF

Change-Id: Iac7ef394c1b3aef9f9eca0ea4cb0f889227801d5
Signed-off-by: Monk Liu <Monk.Liu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c | 107 ++++++++++++++++++----------------
 1 file changed, 57 insertions(+), 50 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
index 848008e..e9cc03e 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
@@ -271,58 +271,65 @@ static int gfx_v9_0_ring_test_ring(struct amdgpu_ring *ring)
 
 static int gfx_v9_0_ring_test_ib(struct amdgpu_ring *ring, long timeout)
 {
-        struct amdgpu_device *adev = ring->adev;
-        struct amdgpu_ib ib;
-        struct dma_fence *f = NULL;
-        uint32_t scratch;
-        uint32_t tmp = 0;
-        long r;
-
-        r = amdgpu_gfx_scratch_get(adev, &scratch);
-        if (r) {
-                DRM_ERROR("amdgpu: failed to get scratch reg (%ld).\n", r);
-                return r;
-        }
-        WREG32(scratch, 0xCAFEDEAD);
-        memset(&ib, 0, sizeof(ib));
-        r = amdgpu_ib_get(adev, NULL, 256, &ib);
-        if (r) {
-                DRM_ERROR("amdgpu: failed to get ib (%ld).\n", r);
-                goto err1;
-        }
-        ib.ptr[0] = PACKET3(PACKET3_SET_UCONFIG_REG, 1);
-        ib.ptr[1] = ((scratch - PACKET3_SET_UCONFIG_REG_START));
-        ib.ptr[2] = 0xDEADBEEF;
-        ib.length_dw = 3;
-
-        r = amdgpu_ib_schedule(ring, 1, &ib, NULL, &f);
-        if (r)
-                goto err2;
-
-        r = dma_fence_wait_timeout(f, false, timeout);
-        if (r == 0) {
-                DRM_ERROR("amdgpu: IB test timed out.\n");
-                r = -ETIMEDOUT;
-                goto err2;
-        } else if (r < 0) {
-                DRM_ERROR("amdgpu: fence wait failed (%ld).\n", r);
-                goto err2;
-        }
-        tmp = RREG32(scratch);
-        if (tmp == 0xDEADBEEF) {
-                DRM_DEBUG("ib test on ring %d succeeded\n", ring->idx);
-                r = 0;
-        } else {
-                DRM_ERROR("amdgpu: ib test failed (scratch(0x%04X)=0x%08X)\n",
-                          scratch, tmp);
-                r = -EINVAL;
-        }
+	struct amdgpu_device *adev = ring->adev;
+	struct amdgpu_ib ib;
+	struct dma_fence *f = NULL;
+
+	unsigned index;
+	uint64_t gpu_addr;
+	uint32_t tmp;
+	long r;
+
+	r = amdgpu_device_wb_get(adev, &index);
+	if (r) {
+		dev_err(adev->dev, "(%ld) failed to allocate wb slot\n", r);
+		return r;
+	}
+
+	gpu_addr = adev->wb.gpu_addr + (index * 4);
+	adev->wb.wb[index] = cpu_to_le32(0xCAFEDEAD);
+	memset(&ib, 0, sizeof(ib));
+	r = amdgpu_ib_get(adev, NULL, 16, &ib);
+	if (r) {
+		DRM_ERROR("amdgpu: failed to get ib (%ld).\n", r);
+		goto err1;
+	}
+	ib.ptr[0] = PACKET3(PACKET3_WRITE_DATA, 3);
+	ib.ptr[1] = WRITE_DATA_DST_SEL(5) | WR_CONFIRM;
+	ib.ptr[2] = lower_32_bits(gpu_addr);
+	ib.ptr[3] = upper_32_bits(gpu_addr);
+	ib.ptr[4] = 0xDEADBEEF;
+	ib.length_dw = 5;
+
+	r = amdgpu_ib_schedule(ring, 1, &ib, NULL, &f);
+	if (r)
+		goto err2;
+
+	r = dma_fence_wait_timeout(f, false, timeout);
+	if (r == 0) {
+			DRM_ERROR("amdgpu: IB test timed out.\n");
+			r = -ETIMEDOUT;
+			goto err2;
+	} else if (r < 0) {
+			DRM_ERROR("amdgpu: fence wait failed (%ld).\n", r);
+			goto err2;
+	}
+
+	tmp = adev->wb.wb[index];
+	if (tmp == 0xDEADBEEF) {
+			DRM_DEBUG("ib test on ring %d succeeded\n", ring->idx);
+			r = 0;
+	} else {
+			DRM_ERROR("ib test on ring %d failed\n", ring->idx);
+			r = -EINVAL;
+	}
+
 err2:
-        amdgpu_ib_free(adev, &ib, NULL);
-        dma_fence_put(f);
+	amdgpu_ib_free(adev, &ib, NULL);
+	dma_fence_put(f);
 err1:
-        amdgpu_gfx_scratch_free(adev, scratch);
-        return r;
+	amdgpu_device_wb_free(adev, index);
+	return r;
 }
 
 
-- 
2.7.4