drm/amdkfd: prepare map process for single process debug devices

Older HW only supports debugging on a single process because the
SPI debug mode setting registers are device global.

The HWS has supplied a single pinned VMID (0xf) for MAP_PROCESS
for debug purposes. To pin the VMID, the KFD will remove the VMID from
the HWS dynamic VMID allocation via SET_RESOUCES so that a debugged
process will never migrate away from its pinned VMID.

The KFD is responsible for reserving and releasing this pinned VMID
accordingly whenever the debugger attaches and detaches respectively.

Signed-off-by: Jonathan Kim <jonathan.kim@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c

@@ -1525,6 +1525,7 @@ static int initialize_cpsch(struct device_queue_manager *dqm)
 	dqm->gws_queue_count = 0;
 	dqm->active_runlist = false;
 	INIT_WORK(&dqm->hw_exception_work, kfd_process_hw_exception);
+	dqm->trap_debug_vmid = 0;
 
 	init_sdma_bitmaps(dqm);
 
@@ -2501,6 +2502,98 @@ static void kfd_process_hw_exception(struct work_struct *work)
 	amdgpu_amdkfd_gpu_reset(dqm->dev->adev);
 }
 
+int reserve_debug_trap_vmid(struct device_queue_manager *dqm,
+				struct qcm_process_device *qpd)
+{
+	int r;
+	int updated_vmid_mask;
+
+	if (dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS) {
+		pr_err("Unsupported on sched_policy: %i\n", dqm->sched_policy);
+		return -EINVAL;
+	}
+
+	dqm_lock(dqm);
+
+	if (dqm->trap_debug_vmid != 0) {
+		pr_err("Trap debug id already reserved\n");
+		r = -EBUSY;
+		goto out_unlock;
+	}
+
+	r = unmap_queues_cpsch(dqm, KFD_UNMAP_QUEUES_FILTER_ALL_QUEUES, 0,
+			USE_DEFAULT_GRACE_PERIOD, false);
+	if (r)
+		goto out_unlock;
+
+	updated_vmid_mask = dqm->dev->kfd->shared_resources.compute_vmid_bitmap;
+	updated_vmid_mask &= ~(1 << dqm->dev->vm_info.last_vmid_kfd);
+
+	dqm->dev->kfd->shared_resources.compute_vmid_bitmap = updated_vmid_mask;
+	dqm->trap_debug_vmid = dqm->dev->vm_info.last_vmid_kfd;
+	r = set_sched_resources(dqm);
+	if (r)
+		goto out_unlock;
+
+	r = map_queues_cpsch(dqm);
+	if (r)
+		goto out_unlock;
+
+	pr_debug("Reserved VMID for trap debug: %i\n", dqm->trap_debug_vmid);
+
+out_unlock:
+	dqm_unlock(dqm);
+	return r;
+}
+
+/*
+ * Releases vmid for the trap debugger
+ */
+int release_debug_trap_vmid(struct device_queue_manager *dqm,
+			struct qcm_process_device *qpd)
+{
+	int r;
+	int updated_vmid_mask;
+	uint32_t trap_debug_vmid;
+
+	if (dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS) {
+		pr_err("Unsupported on sched_policy: %i\n", dqm->sched_policy);
+		return -EINVAL;
+	}
+
+	dqm_lock(dqm);
+	trap_debug_vmid = dqm->trap_debug_vmid;
+	if (dqm->trap_debug_vmid == 0) {
+		pr_err("Trap debug id is not reserved\n");
+		r = -EINVAL;
+		goto out_unlock;
+	}
+
+	r = unmap_queues_cpsch(dqm, KFD_UNMAP_QUEUES_FILTER_ALL_QUEUES, 0,
+			USE_DEFAULT_GRACE_PERIOD, false);
+	if (r)
+		goto out_unlock;
+
+	updated_vmid_mask = dqm->dev->kfd->shared_resources.compute_vmid_bitmap;
+	updated_vmid_mask |= (1 << dqm->dev->vm_info.last_vmid_kfd);
+
+	dqm->dev->kfd->shared_resources.compute_vmid_bitmap = updated_vmid_mask;
+	dqm->trap_debug_vmid = 0;
+	r = set_sched_resources(dqm);
+	if (r)
+		goto out_unlock;
+
+	r = map_queues_cpsch(dqm);
+	if (r)
+		goto out_unlock;
+
+	pr_debug("Released VMID for trap debug: %i\n", trap_debug_vmid);
+
+out_unlock:
+	dqm_unlock(dqm);
+	return r;
+}
+
 #if defined(CONFIG_DEBUG_FS)
 
 static void seq_reg_dump(struct seq_file *m,

drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h

@@ -250,6 +250,7 @@ struct device_queue_manager {
 	struct kfd_mem_obj	*fence_mem;
 	bool			active_runlist;
 	int			sched_policy;
+	uint32_t		trap_debug_vmid;
 
 	/* hw exception  */
 	bool			is_hws_hang;
@@ -285,6 +286,10 @@ unsigned int get_queues_per_pipe(struct device_queue_manager *dqm);
 unsigned int get_pipes_per_mec(struct device_queue_manager *dqm);
 unsigned int get_num_sdma_queues(struct device_queue_manager *dqm);
 unsigned int get_num_xgmi_sdma_queues(struct device_queue_manager *dqm);
+int reserve_debug_trap_vmid(struct device_queue_manager *dqm,
+			struct qcm_process_device *qpd);
+int release_debug_trap_vmid(struct device_queue_manager *dqm,
+			struct qcm_process_device *qpd);
 
 static inline unsigned int get_sh_mem_bases_32(struct kfd_process_device *pdd)
 {

drivers/gpu/drm/amd/amdkfd/kfd_packet_manager_v9.c

@@ -34,6 +34,9 @@ static int pm_map_process_v9(struct packet_manager *pm,
 {
 	struct pm4_mes_map_process *packet;
 	uint64_t vm_page_table_base_addr = qpd->page_table_base;
+	struct kfd_node *kfd = pm->dqm->dev;
+	struct kfd_process_device *pdd =
+			container_of(qpd, struct kfd_process_device, qpd);
 
 	packet = (struct pm4_mes_map_process *)buffer;
 	memset(buffer, 0, sizeof(struct pm4_mes_map_process));
@@ -49,6 +52,12 @@ static int pm_map_process_v9(struct packet_manager *pm,
 	packet->bitfields14.sdma_enable = 1;
 	packet->bitfields14.num_queues = (qpd->is_debug) ? 0 : qpd->queue_count;
 
+	if (kfd->dqm->trap_debug_vmid && pdd->process->debug_trap_enabled &&
+			pdd->process->runtime_info.runtime_state == DEBUG_RUNTIME_STATE_ENABLED) {
+		packet->bitfields2.debug_vmid = kfd->dqm->trap_debug_vmid;
+		packet->bitfields2.new_debug = 1;
+	}
+
 	packet->sh_mem_config = qpd->sh_mem_config;
 	packet->sh_mem_bases = qpd->sh_mem_bases;
 	if (qpd->tba_addr) {

drivers/gpu/drm/amd/amdkfd/kfd_pm4_headers_ai.h

@@ -146,7 +146,10 @@ struct pm4_mes_map_process {
 	union {
 		struct {
 			uint32_t pasid:16;
-			uint32_t reserved1:8;
+			uint32_t reserved1:2;
+			uint32_t debug_vmid:4;
+			uint32_t new_debug:1;
+			uint32_t reserved2:1;
 			uint32_t diq_enable:1;
 			uint32_t process_quantum:7;
 		} bitfields2;