[PATCH v4 04/10] drm/amdgpu/mes_userqueue: mark SDMA UMQs as user-mode submission

[Jesse Zhang <Jesse.Zhang@amd.com>]

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From: "Jesse.zhang" <Jesse.zhang@amd.com>

For AMDGPU_HW_IP_DMA queues, set mes_add_queue_input.is_user_mode_submission
and a stable unmap_flag_addr (a kernel-owned dword in the MQD
object's tail padding).  This tells MES to use the new wptr_mc /
unmap_flag scheme so the PROTECTED_FENCE at the tail of every SDMA
IB no longer terminates the queue.  Combined with the
NOTIFY_WORK_ON_UNMAPPED_QUEUE wakeup added in a follow-up patch, this
lets multi-IB submissions on a single SDMA UMQ work end-to-end.

Signed-off-by: Jesse Zhang <Jesse.Zhang@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/mes_userqueue.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/mes_userqueue.c b/drivers/gpu/drm/amd/amdgpu/mes_userqueue.c
index d12cd1b7790b..3dbcddb46b24 100644
--- a/drivers/gpu/drm/amd/amdgpu/mes_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/mes_userqueue.c
@@ -165,6 +165,28 @@ static int mes_userq_map(struct amdgpu_usermode_queue *queue)
 	queue_input.doorbell_offset = userq_props->doorbell_index;
 	queue_input.page_table_base_addr = amdgpu_gmc_pd_addr(queue->vm->root.bo);
 	queue_input.wptr_mc_addr = queue->wptr_obj.gpu_addr;
+	/*
+	 * SDMA UMQs need is_user_mode_submission so MES treats them as user
+	 * queues (using the new wptr_mc_addr / unmap_flag_addr scheme).
+	 * Without this MES uses end-of-MQD for unmap_flag, sees PROTECTED_FENCE
+	 * as a "queue done" signal, and gangs the queue out forever.  Combined
+	 * with NOTIFY_WORK_ON_UNMAPPED_QUEUE poke from amdgpu_userq_signal_ioctl
+	 * this lets multi-IB submissions work.  Use queue->mqd.gpu_addr +
+	 * mqd_size as a stable kernel-owned location for unmap_flag — userspace
+	 * never reads it; the kernel just needs SOMETHING valid to give MES.
+	 */
+	if (queue->queue_type == AMDGPU_HW_IP_DMA) {
+		queue_input.is_user_mode_submission = 1;
+		/*
+		 * Same offset MES would derive in legacy mode
+		 * (get_unmap_flag_addr_from_end_of_mqd in MES src 12).  Lives
+		 * inside the allocated MQD object's tail padding so it's a
+		 * valid MC address; the kernel never reads it back — its only
+		 * purpose is to keep MES happy.
+		 */
+		queue_input.unmap_flag_addr = queue->mqd.gpu_addr +
+			adev->mqds[queue->queue_type].mqd_size + sizeof(u32);
+	}
 
 	amdgpu_mes_lock(&adev->mes);
 	r = adev->mes.funcs->add_hw_queue(&adev->mes, &queue_input);
-- 
2.49.0