[PATCH v3 9/9] drm/amdgpu: generate doorbell index for userqueue

[Shashank Sharma]

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 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 | 35 +++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
index 7409a4ae55da..fd4a2ca3302d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
@@ -43,6 +43,32 @@ 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)
 {
@@ -132,6 +158,7 @@ static int amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq
     struct amdgpu_fpriv *fpriv = filp->driver_priv;
     struct amdgpu_userq_mgr *uq_mgr = &fpriv->userq_mgr;
     struct drm_amdgpu_userq_mqd *mqd_in = &args->in.mqd;
+    uint64_t index;
     int r;
 
     /* Do we have support userqueues for this IP ? */
@@ -154,6 +181,14 @@ static int amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq
     queue->userq_prop.queue_size = mqd_in->queue_size;
 
     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->shadow_ctx_gpu_addr = mqd_in->shadow_va;
     queue->queue_type = mqd_in->ip_type;
     queue->flags = mqd_in->flags;
-- 
2.40.0