[PATCH v6 7/9] drm/amdgpu: map wptr BO into GART

[Shashank Sharma]

To support oversubscription, MES FW expects WPTR BOs to
be mapped into GART, before they are submitted to usermode
queues. This patch adds a function for the same.

V4: fix the wptr value before mapping lookup (Bas, Christian).
V5: Addressed review comments from Christian:
    - Either pin object or allocate from GART, but not both.
    - All the handling must be done with the VM locks held.

Cc: Alex Deucher <alexander.deucher at amd.com>
Cc: Christian Koenig <christian.koenig at amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
Signed-off-by: Arvind Yadav <arvind.yadav at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c        | 81 +++++++++++++++++++
 .../gpu/drm/amd/include/amdgpu_userqueue.h    |  1 +
 2 files changed, 82 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
index e266674e0d44..c0eb622dfc37 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
@@ -6427,6 +6427,79 @@ const struct amdgpu_ip_block_version gfx_v11_0_ip_block =
 	.funcs = &gfx_v11_0_ip_funcs,
 };
 
+static int
+gfx_v11_0_map_gtt_bo_to_gart(struct amdgpu_device *adev, struct amdgpu_bo *bo)
+{
+	int ret;
+
+	ret = amdgpu_bo_reserve(bo, true);
+	if (ret) {
+		DRM_ERROR("Failed to reserve bo. ret %d\n", ret);
+		goto err_reserve_bo_failed;
+	}
+
+	ret = amdgpu_ttm_alloc_gart(&bo->tbo);
+	if (ret) {
+		DRM_ERROR("Failed to bind bo to GART. ret %d\n", ret);
+		goto err_map_bo_gart_failed;
+	}
+
+	amdgpu_bo_unreserve(bo);
+	bo = amdgpu_bo_ref(bo);
+
+	return 0;
+
+err_map_bo_gart_failed:
+	amdgpu_bo_unreserve(bo);
+err_reserve_bo_failed:
+	return ret;
+}
+
+static int
+gfx_v11_0_create_wptr_mapping(struct amdgpu_device *adev,
+			      struct amdgpu_usermode_queue *queue,
+			      uint64_t wptr)
+{
+	struct amdgpu_bo_va_mapping *wptr_mapping;
+	struct amdgpu_vm *wptr_vm;
+	struct amdgpu_bo *wptr_bo = NULL;
+	int ret;
+
+	mutex_lock(&queue->vm->eviction_lock);
+	wptr_vm = queue->vm;
+	ret = amdgpu_bo_reserve(wptr_vm->root.bo, false);
+	if (ret)
+		goto unlock;
+
+	wptr &= AMDGPU_GMC_HOLE_MASK;
+	wptr_mapping = amdgpu_vm_bo_lookup_mapping(wptr_vm, wptr >> PAGE_SHIFT);
+	amdgpu_bo_unreserve(wptr_vm->root.bo);
+	if (!wptr_mapping) {
+		DRM_ERROR("Failed to lookup wptr bo\n");
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	wptr_bo = wptr_mapping->bo_va->base.bo;
+	if (wptr_bo->tbo.base.size > PAGE_SIZE) {
+		DRM_ERROR("Requested GART mapping for wptr bo larger than one page\n");
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	ret = gfx_v11_0_map_gtt_bo_to_gart(adev, wptr_bo);
+	if (ret) {
+		DRM_ERROR("Failed to map wptr bo to GART\n");
+		goto unlock;
+	}
+
+	queue->wptr_mc_addr = wptr_bo->tbo.resource->start << PAGE_SHIFT;
+
+unlock:
+	mutex_unlock(&queue->vm->eviction_lock);
+	return ret;
+}
+
 static void gfx_v11_0_userq_unmap(struct amdgpu_userq_mgr *uq_mgr,
 				  struct amdgpu_usermode_queue *queue)
 {
@@ -6475,6 +6548,7 @@ static int gfx_v11_0_userq_map(struct amdgpu_userq_mgr *uq_mgr,
 	queue_input.queue_size = userq_props->queue_size >> 2;
 	queue_input.doorbell_offset = userq_props->doorbell_index;
 	queue_input.page_table_base_addr = amdgpu_gmc_pd_addr(queue->vm->root.bo);
+	queue_input.wptr_mc_addr = queue->wptr_mc_addr;
 
 	amdgpu_mes_lock(&adev->mes);
 	r = adev->mes.funcs->add_hw_queue(&adev->mes, &queue_input);
@@ -6601,6 +6675,13 @@ static int gfx_v11_0_userq_mqd_create(struct amdgpu_userq_mgr *uq_mgr,
 		goto free_mqd;
 	}
 
+	/* FW expects WPTR BOs to be mapped into GART */
+	r = gfx_v11_0_create_wptr_mapping(adev, queue, userq_props.wptr_gpu_addr);
+	if (r) {
+		DRM_ERROR("Failed to create WPTR mapping\n");
+		goto free_ctx;
+	}
+
 	/* Map userqueue into FW using MES */
 	r = gfx_v11_0_userq_map(uq_mgr, queue, &userq_props);
 	if (r) {
diff --git a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
index 34e20daa06c8..ae155de62560 100644
--- a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
+++ b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
@@ -39,6 +39,7 @@ struct amdgpu_usermode_queue {
 	int			queue_type;
 	uint64_t		doorbell_handle;
 	uint64_t		doorbell_index;
+	uint64_t		wptr_mc_addr;
 	uint64_t		flags;
 	struct amdgpu_mqd_prop	*userq_prop;
 	struct amdgpu_userq_mgr *userq_mgr;
-- 
2.42.0