[RFC 4/7] drm/amdgpu: Allocate doorbell slot for user queue

[Shashank Sharma]

This patch allocates a doorbell slot in the bar, for the usermode queue.
We are using the unique queue-id to get this slot from MES.

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>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
index a91cc304cb9e..b566ce4cb7f0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
@@ -50,6 +50,25 @@ amdgpu_userqueue_remove_index(struct amdgpu_device *adev, struct amdgpu_usermode
     ida_simple_remove(&uqg->ida, queue->queue_id);
 }
 
+static int
+amdgpu_userqueue_get_doorbell(struct amdgpu_device *adev,
+                    struct amdgpu_usermode_queue *queue)
+{
+    int r;
+    unsigned int doorbell_index;
+
+    r = amdgpu_mes_alloc_process_doorbells(adev, &doorbell_index);
+	if (r < 0) {
+        DRM_ERROR("Failed to allocate doorbell for user queue\n");
+        return r;
+    }
+
+    /* We are using qnique queue-id to get doorbell here */
+    queue->doorbell_index = amdgpu_mes_get_doorbell_dw_offset_in_bar(adev,
+			    doorbell_index, queue->queue_id);
+    return 0;
+}
+
 static void
 amdgpu_userqueue_setup_mqd(struct amdgpu_device *adev, struct amdgpu_usermode_queue *queue)
 {
@@ -257,12 +276,21 @@ int amdgpu_userqueue_create(struct amdgpu_device *adev, struct drm_file *filp,
         goto free_queue;
     }
 
+    r = amdgpu_userqueue_get_doorbell(adev, queue);
+    if (r) {
+        DRM_ERROR("Failed to create doorbell for queue\n");
+        goto free_mqd;
+    }
+
     ctx->userq = queue;
     args->out.q_id = queue->queue_id;
     args->out.flags = 0;
     mutex_unlock(&adev->userq.userq_mutex);
     return 0;
 
+free_mqd:
+    amdgpu_userqueue_destroy_mqd(queue);
+
 free_queue:
     amdgpu_userqueue_remove_index(adev, queue);
     mutex_unlock(&adev->userq.userq_mutex);
-- 
2.34.1