drm/amdgpu: avoid KIQ clashing with compute or KFD queues v2

Instead of picking an arbitrary queue for KIQ, search for one according
to policy. The queue must be unused.

Also report the KIQ as an unavailable resource to KFD.

In testing I ran into KCQ initialization issues when using pipes 2/3 of
MEC2 for the KIQ. Therefore the policy disallows grabbing one of these.

v2: fix (ring.me + 1) to (ring.me -1) in amdgpu_amdkfd_device_init

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 35 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
index bd0b2310f1d9..0a7ee4d55816 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
@@ -1378,6 +1378,37 @@ static void gfx_v8_0_mec_fini(struct amdgpu_device *adev)
 	}
 }
 
+static int gfx_v8_0_kiq_acquire(struct amdgpu_device *adev,
+				 struct amdgpu_ring *ring)
+{
+	int queue_bit;
+	int mec, pipe, queue;
+
+	queue_bit = adev->gfx.mec.num_mec
+		    * adev->gfx.mec.num_pipe_per_mec
+		    * adev->gfx.mec.num_queue_per_pipe;
+
+	while (queue_bit-- >= 0) {
+		if (test_bit(queue_bit, adev->gfx.mec.queue_bitmap))
+			continue;
+
+		amdgpu_bit_to_queue(adev, queue_bit, &mec, &pipe, &queue);
+
+		/* Using pipes 2/3 from MEC 2 seems cause problems */
+		if (mec == 1 && pipe > 1)
+			continue;
+
+		ring->me = mec + 1;
+		ring->pipe = pipe;
+		ring->queue = queue;
+
+		return 0;
+	}
+
+	dev_err(adev->dev, "Failed to find a queue for KIQ\n");
+	return -EINVAL;
+}
+
 static int gfx_v8_0_kiq_init_ring(struct amdgpu_device *adev,
 				  struct amdgpu_ring *ring,
 				  struct amdgpu_irq_src *irq)
@@ -1395,15 +1426,11 @@ static int gfx_v8_0_kiq_init_ring(struct amdgpu_device *adev,
 	ring->ring_obj = NULL;
 	ring->use_doorbell = true;
 	ring->doorbell_index = AMDGPU_DOORBELL_KIQ;
-	if (adev->gfx.mec2_fw) {
-		ring->me = 2;
-		ring->pipe = 0;
-	} else {
-		ring->me = 1;
-		ring->pipe = 1;
-	}
 
-	ring->queue = 0;
+	r = gfx_v8_0_kiq_acquire(adev, ring);
+	if (r)
+		return r;
+
 	ring->eop_gpu_addr = kiq->eop_gpu_addr;
 	sprintf(ring->name, "kiq %d.%d.%d", ring->me, ring->pipe, ring->queue);
 	r = amdgpu_ring_init(adev, ring, 1024,