drm/amdkfd: Preserve CP_MQD_IQ_RPTR internal state

CP microcode uses undocumented bits in this register to record queue
state information. The KFD zeroes these bits in update_mqd, when invoked
through the UPDATE_QUEUE ioctl, causing incoherent state when the ioctl
is used to successively unmap and map a queue.

Since the queue type cannot be changed in this path, move the MQD write
to init_mqd.

Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Ben Goz <ben.goz@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@amd.com>

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_cik.c b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_cik.c
index a318743cdcc2cce1a4b915c962fadb92d13445f0..a09e18a339f34ef1268ce9ccd8c6ef0804c9ff76 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_cik.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_cik.c
@@ -94,6 +94,9 @@ static int init_mqd(struct mqd_manager *mm, void **mqd,
        m->cp_hqd_pipe_priority = 1;
        m->cp_hqd_queue_priority = 15;
 
+       if (q->format == KFD_QUEUE_FORMAT_AQL)
+               m->cp_hqd_iq_rptr = AQL_ENABLE;
+
        *mqd = m;
        if (gart_addr != NULL)
                *gart_addr = addr;
@@ -187,7 +190,6 @@ static int update_mqd(struct mqd_manager *mm, void *mqd,
        m->cp_hqd_vmid = q->vmid;
 
        if (q->format == KFD_QUEUE_FORMAT_AQL) {
-               m->cp_hqd_iq_rptr = AQL_ENABLE;
                m->cp_hqd_pq_control |= NO_UPDATE_RPTR;
        }