drm/amdgpu: invalidate mmhub semaphore workaround in gmc9/gmc10
authorchangzhu <Changfeng.Zhu@amd.com>
Tue, 19 Nov 2019 03:13:29 +0000 (11:13 +0800)
committerAlex Deucher <alexander.deucher@amd.com>
Fri, 22 Nov 2019 19:55:19 +0000 (14:55 -0500)
It may lose gpuvm invalidate acknowldege state across power-gating off
cycle. To avoid this issue in gmc9/gmc10 invalidation, add semaphore acquire
before invalidation and semaphore release after invalidation.

After adding semaphore acquire before invalidation, the semaphore
register become read-only if another process try to acquire semaphore.
Then it will not be able to release this semaphore. Then it may cause
deadlock problem. If this deadlock problem happens, it needs a semaphore
firmware fix.

Signed-off-by: changzhu <Changfeng.Zhu@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
drivers/gpu/drm/amd/amdgpu/soc15.h

index 27f68d32bfec10fa8cf12f14092f381134a4a89f..321f8a997be8e1ce44ea77ee4228b5237277c9ad 100644 (file)
@@ -235,6 +235,29 @@ static void gmc_v10_0_flush_vm_hub(struct amdgpu_device *adev, uint32_t vmid,
        const unsigned eng = 17;
        unsigned int i;
 
+       spin_lock(&adev->gmc.invalidate_lock);
+       /*
+        * It may lose gpuvm invalidate acknowldege state across power-gating
+        * off cycle, add semaphore acquire before invalidation and semaphore
+        * release after invalidation to avoid entering power gated state
+        * to WA the Issue
+        */
+
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (vmhub == AMDGPU_MMHUB_0 ||
+           vmhub == AMDGPU_MMHUB_1) {
+               for (i = 0; i < adev->usec_timeout; i++) {
+                       /* a read return value of 1 means semaphore acuqire */
+                       tmp = RREG32_NO_KIQ(hub->vm_inv_eng0_sem + eng);
+                       if (tmp & 0x1)
+                               break;
+                       udelay(1);
+               }
+
+               if (i >= adev->usec_timeout)
+                       DRM_ERROR("Timeout waiting for sem acquire in VM flush!\n");
+       }
+
        WREG32_NO_KIQ(hub->vm_inv_eng0_req + eng, tmp);
 
        /*
@@ -254,6 +277,17 @@ static void gmc_v10_0_flush_vm_hub(struct amdgpu_device *adev, uint32_t vmid,
                udelay(1);
        }
 
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (vmhub == AMDGPU_MMHUB_0 ||
+           vmhub == AMDGPU_MMHUB_1)
+               /*
+                * add semaphore release after invalidation,
+                * write with 0 means semaphore release
+                */
+               WREG32_NO_KIQ(hub->vm_inv_eng0_sem + eng, 0);
+
+       spin_unlock(&adev->gmc.invalidate_lock);
+
        if (i < adev->usec_timeout)
                return;
 
@@ -338,6 +372,20 @@ static uint64_t gmc_v10_0_emit_flush_gpu_tlb(struct amdgpu_ring *ring,
        uint32_t req = gmc_v10_0_get_invalidate_req(vmid, 0);
        unsigned eng = ring->vm_inv_eng;
 
+       /*
+        * It may lose gpuvm invalidate acknowldege state across power-gating
+        * off cycle, add semaphore acquire before invalidation and semaphore
+        * release after invalidation to avoid entering power gated state
+        * to WA the Issue
+        */
+
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (ring->funcs->vmhub == AMDGPU_MMHUB_0 ||
+           ring->funcs->vmhub == AMDGPU_MMHUB_1)
+               /* a read return value of 1 means semaphore acuqire */
+               amdgpu_ring_emit_reg_wait(ring,
+                                         hub->vm_inv_eng0_sem + eng, 0x1, 0x1);
+
        amdgpu_ring_emit_wreg(ring, hub->ctx0_ptb_addr_lo32 + (2 * vmid),
                              lower_32_bits(pd_addr));
 
@@ -348,6 +396,15 @@ static uint64_t gmc_v10_0_emit_flush_gpu_tlb(struct amdgpu_ring *ring,
                                            hub->vm_inv_eng0_ack + eng,
                                            req, 1 << vmid);
 
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (ring->funcs->vmhub == AMDGPU_MMHUB_0 ||
+           ring->funcs->vmhub == AMDGPU_MMHUB_1)
+               /*
+                * add semaphore release after invalidation,
+                * write with 0 means semaphore release
+                */
+               amdgpu_ring_emit_wreg(ring, hub->vm_inv_eng0_sem + eng, 0);
+
        return pd_addr;
 }
 
index 9f2a893871ecd21a01da46837fb75ff9cd9bebca..3c355fb5d2b47227621c220115ebc1957841399a 100644 (file)
@@ -459,6 +459,29 @@ static void gmc_v9_0_flush_gpu_tlb(struct amdgpu_device *adev, uint32_t vmid,
        }
 
        spin_lock(&adev->gmc.invalidate_lock);
+
+       /*
+        * It may lose gpuvm invalidate acknowldege state across power-gating
+        * off cycle, add semaphore acquire before invalidation and semaphore
+        * release after invalidation to avoid entering power gated state
+        * to WA the Issue
+        */
+
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (vmhub == AMDGPU_MMHUB_0 ||
+           vmhub == AMDGPU_MMHUB_1) {
+               for (j = 0; j < adev->usec_timeout; j++) {
+                       /* a read return value of 1 means semaphore acuqire */
+                       tmp = RREG32_NO_KIQ(hub->vm_inv_eng0_sem + eng);
+                       if (tmp & 0x1)
+                               break;
+                       udelay(1);
+               }
+
+               if (j >= adev->usec_timeout)
+                       DRM_ERROR("Timeout waiting for sem acquire in VM flush!\n");
+       }
+
        WREG32_NO_KIQ(hub->vm_inv_eng0_req + eng, tmp);
 
        /*
@@ -474,7 +497,18 @@ static void gmc_v9_0_flush_gpu_tlb(struct amdgpu_device *adev, uint32_t vmid,
                        break;
                udelay(1);
        }
+
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (vmhub == AMDGPU_MMHUB_0 ||
+           vmhub == AMDGPU_MMHUB_1)
+               /*
+                * add semaphore release after invalidation,
+                * write with 0 means semaphore release
+                */
+               WREG32_NO_KIQ(hub->vm_inv_eng0_sem + eng, 0);
+
        spin_unlock(&adev->gmc.invalidate_lock);
+
        if (j < adev->usec_timeout)
                return;
 
@@ -489,6 +523,20 @@ static uint64_t gmc_v9_0_emit_flush_gpu_tlb(struct amdgpu_ring *ring,
        uint32_t req = gmc_v9_0_get_invalidate_req(vmid, 0);
        unsigned eng = ring->vm_inv_eng;
 
+       /*
+        * It may lose gpuvm invalidate acknowldege state across power-gating
+        * off cycle, add semaphore acquire before invalidation and semaphore
+        * release after invalidation to avoid entering power gated state
+        * to WA the Issue
+        */
+
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (ring->funcs->vmhub == AMDGPU_MMHUB_0 ||
+           ring->funcs->vmhub == AMDGPU_MMHUB_1)
+               /* a read return value of 1 means semaphore acuqire */
+               amdgpu_ring_emit_reg_wait(ring,
+                                         hub->vm_inv_eng0_sem + eng, 0x1, 0x1);
+
        amdgpu_ring_emit_wreg(ring, hub->ctx0_ptb_addr_lo32 + (2 * vmid),
                              lower_32_bits(pd_addr));
 
@@ -499,6 +547,15 @@ static uint64_t gmc_v9_0_emit_flush_gpu_tlb(struct amdgpu_ring *ring,
                                            hub->vm_inv_eng0_ack + eng,
                                            req, 1 << vmid);
 
+       /* TODO: It needs to continue working on debugging with semaphore for GFXHUB as well. */
+       if (ring->funcs->vmhub == AMDGPU_MMHUB_0 ||
+           ring->funcs->vmhub == AMDGPU_MMHUB_1)
+               /*
+                * add semaphore release after invalidation,
+                * write with 0 means semaphore release
+                */
+               amdgpu_ring_emit_wreg(ring, hub->vm_inv_eng0_sem + eng, 0);
+
        return pd_addr;
 }
 
index 9af6c6ffbfa2b8b1c312633f4811c56a7a7ba4b6..57af489a5de3ec7f4bcdc7f31998f9e8ee594ab1 100644 (file)
@@ -28,8 +28,8 @@
 #include "nbio_v7_0.h"
 #include "nbio_v7_4.h"
 
-#define SOC15_FLUSH_GPU_TLB_NUM_WREG           4
-#define SOC15_FLUSH_GPU_TLB_NUM_REG_WAIT       1
+#define SOC15_FLUSH_GPU_TLB_NUM_WREG           6
+#define SOC15_FLUSH_GPU_TLB_NUM_REG_WAIT       3
 
 extern const struct amd_ip_funcs soc15_common_ip_funcs;