From: Felix Kuehling <Felix.Kuehling@amd.com>
Date: Wed, 27 Sep 2017 00:09:55 -0400
Subject: drm/amdkfd: Limit queue number per process and device to 127
Git-commit: 36c2d7eb5e99a4d765b1ec241823d563c71b1125
Patch-mainline: v4.15-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

HWS uses bit 7 in the queue number of the map process packet for an
undocumented feature. Therefore the queue number per process and
device must be 127 or less.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
@@ -150,6 +150,7 @@ int pqm_create_queue(struct process_queu
 	struct process_queue_node *pqn;
 	struct kernel_queue *kq;
 	enum kfd_queue_type type = properties->type;
+	unsigned int max_queues = 127; /* HWS limit */
 
 	q = NULL;
 	kq = NULL;
@@ -166,10 +167,11 @@ int pqm_create_queue(struct process_queu
 	 * If we are just about to create DIQ, the is_debug flag is not set yet
 	 * Hence we also check the type as well
 	 */
-	if ((pdd->qpd.is_debug) || (type == KFD_QUEUE_TYPE_DIQ)) {
-		if (pdd->qpd.queue_count >= dev->device_info->max_no_of_hqd/2)
-			return -ENOSPC;
-	}
+	if ((pdd->qpd.is_debug) || (type == KFD_QUEUE_TYPE_DIQ))
+		max_queues = dev->device_info->max_no_of_hqd/2;
+
+	if (pdd->qpd.queue_count >= max_queues)
+		return -ENOSPC;
 
 	retval = find_available_queue_slot(pqm, qid);
 	if (retval != 0)