[PATCH v4 09/10] drm/amdgpu: generate doorbell index for userqueue

[Shashank Sharma <shashank.sharma@amd.com>]

The userspace sends us the doorbell object and the doobell index
to be used for the usermode queue, but the FW expects the absolute
doorbell index on the PCI BAR in the MQD. This patch adds a function
to convert this relative doorbell index to the absolute doorbell index.

This patch is dependent on the doorbell manager series being reviewed
here: https://patchwork.freedesktop.org/series/115802/

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
index 385cd51b6c96..fbc9cb5c24ad 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
@@ -44,6 +44,30 @@ amdgpu_userqueue_find(struct amdgpu_userq_mgr *uq_mgr, int qid)
 	return idr_find(&uq_mgr->userq_idr, qid);
 }
 
+static uint64_t
+amdgpu_userqueue_get_doorbell_index(struct amdgpu_userq_mgr *uq_mgr,
+				    struct amdgpu_usermode_queue *queue,
+				    struct drm_file *filp,
+				    uint32_t doorbell_index)
+{
+	struct drm_gem_object *gobj;
+	struct amdgpu_bo *db_bo;
+	uint64_t index;
+
+	gobj = drm_gem_object_lookup(filp, queue->doorbell_handle);
+	if (gobj == NULL) {
+		DRM_ERROR("Can't find GEM object for doorbell\n");
+		return -EINVAL;
+	}
+
+	db_bo = amdgpu_bo_ref(gem_to_amdgpu_bo(gobj));
+	drm_gem_object_put(gobj);
+
+	index = amdgpu_doorbell_index_on_bar(uq_mgr->adev, db_bo, doorbell_index);
+	DRM_DEBUG_DRIVER("[Usermode queues] doorbell index=%lld\n", index);
+	return index;
+}
+
 static int
 amdgpu_userqueue_map_gtt_bo_to_gart(struct amdgpu_device *adev, struct amdgpu_bo *bo)
 {
@@ -133,6 +157,7 @@ static int amdgpu_userqueue_create_gfx(struct drm_file *filp, union drm_amdgpu_u
 	struct amdgpu_fpriv *fpriv = filp->driver_priv;
 	struct amdgpu_userq_mgr *uq_mgr = &fpriv->userq_mgr;
 	struct drm_amdgpu_userq_mqd_gfx *mqd_in = &args->in.mqd.gfx;
+	uint64_t index;
 	int r;
 
 	/* Do we support usermode queues on this GFX IP ? */
@@ -154,6 +179,14 @@ static int amdgpu_userqueue_create_gfx(struct drm_file *filp, union drm_amdgpu_u
 	queue->userq_prop.hqd_base_gpu_addr = mqd_in->queue_va;
 
 	queue->doorbell_handle = mqd_in->doorbell_handle;
+	index = amdgpu_userqueue_get_doorbell_index(uq_mgr, queue, filp, mqd_in->doorbell_offset);
+	if (index == (uint64_t)-EINVAL) {
+		DRM_ERROR("Invalid doorbell object\n");
+		r = -EINVAL;
+		goto free_queue;
+	}
+
+	queue->userq_prop.doorbell_index = index;
 	queue->queue_type = AMDGPU_HW_IP_GFX;
 	queue->flags = mqd_in->flags;
 	queue->vm = &fpriv->vm;
-- 
2.40.0