[PATCH] drm/amdgpu: drop kiq access while in reset

[Vignesh Chander]

correctly handle the case when trylock fails when gpu is
about to be reset by dropping the request instead of using mmio

Signed-off-by: Vignesh Chander <Vignesh.Chander at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 38 ++++++++++++----------
 1 file changed, 21 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index a7ce8280b17ce7..3cfd24699d691d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -613,10 +613,11 @@ uint32_t amdgpu_device_rreg(struct amdgpu_device *adev,
 
 	if ((reg * 4) < adev->rmmio_size) {
 		if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
-		    amdgpu_sriov_runtime(adev) &&
-		    down_read_trylock(&adev->reset_domain->sem)) {
-			ret = amdgpu_kiq_rreg(adev, reg, 0);
-			up_read(&adev->reset_domain->sem);
+		    amdgpu_sriov_runtime(adev) {
+			if (down_read_trylock(&adev->reset_domain->sem)) {
+				ret = amdgpu_kiq_rreg(adev, reg, 0);
+				up_read(&adev->reset_domain->sem);
+			}
 		} else {
 			ret = readl(((void __iomem *)adev->rmmio) + (reg * 4));
 		}
@@ -681,10 +682,11 @@ uint32_t amdgpu_device_xcc_rreg(struct amdgpu_device *adev,
 							 &rlcg_flag)) {
 			ret = amdgpu_virt_rlcg_reg_rw(adev, reg, 0, rlcg_flag, GET_INST(GC, xcc_id));
 		} else if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
-		    amdgpu_sriov_runtime(adev) &&
-		    down_read_trylock(&adev->reset_domain->sem)) {
-			ret = amdgpu_kiq_rreg(adev, reg, xcc_id);
-			up_read(&adev->reset_domain->sem);
+		    amdgpu_sriov_runtime(adev) {
+			if (down_read_trylock(&adev->reset_domain->sem)) {
+				ret = amdgpu_kiq_rreg(adev, reg, xcc_id);
+				up_read(&adev->reset_domain->sem);
+			}
 		} else {
 			ret = readl(((void __iomem *)adev->rmmio) + (reg * 4));
 		}
@@ -740,10 +742,11 @@ void amdgpu_device_wreg(struct amdgpu_device *adev,
 
 	if ((reg * 4) < adev->rmmio_size) {
 		if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
-		    amdgpu_sriov_runtime(adev) &&
-		    down_read_trylock(&adev->reset_domain->sem)) {
-			amdgpu_kiq_wreg(adev, reg, v, 0);
-			up_read(&adev->reset_domain->sem);
+		    amdgpu_sriov_runtime(adev) {
+			if (down_read_trylock(&adev->reset_domain->sem)) {
+				amdgpu_kiq_wreg(adev, reg, v, 0);
+				up_read(&adev->reset_domain->sem);
+			}
 		} else {
 			writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
 		}
@@ -812,11 +815,12 @@ void amdgpu_device_xcc_wreg(struct amdgpu_device *adev,
 							 &rlcg_flag)) {
 			amdgpu_virt_rlcg_reg_rw(adev, reg, v, rlcg_flag, GET_INST(GC, xcc_id));
 		} else if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
-		    amdgpu_sriov_runtime(adev) &&
-		    down_read_trylock(&adev->reset_domain->sem)) {
-			amdgpu_kiq_wreg(adev, reg, v, xcc_id);
-			up_read(&adev->reset_domain->sem);
-		} else {
+		    amdgpu_sriov_runtime(adev) {
+			if (down_read_trylock(&adev->reset_domain->sem)) {
+				amdgpu_kiq_wreg(adev, reg, v, xcc_id);
+				up_read(&adev->reset_domain->sem);
+			}
+		    } else {
 			writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
 		}
 	} else {
-- 
2.25.1