accel/ivpu: Improve recovery and reset support

- Synchronize job submission with reset/recovery using reset_lock
  - Always print recovery reason and call diagnose_failure()
  - Don't allow for autosupend during recovery
  - Prevent immediate autosuspend after reset/recovery
  - Prevent force_recovery for issuing TDR when device is suspended
  - Reset VPU instead triggering recovery after changing debugfs params

Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Wachowski, Karol <karol.wachowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240122120945.1150728-4-jacek.lawrynowicz@linux.intel.com

drivers/accel/ivpu/ivpu_debugfs.c

@@ -102,7 +102,7 @@ static int reset_pending_show(struct seq_file *s, void *v)
 {
 	struct ivpu_device *vdev = seq_to_ivpu(s);
 
-	seq_printf(s, "%d\n", atomic_read(&vdev->pm->in_reset));
+	seq_printf(s, "%d\n", atomic_read(&vdev->pm->reset_pending));
 	return 0;
 }
 
@@ -130,7 +130,9 @@ dvfs_mode_fops_write(struct file *file, const char __user *user_buf, size_t size
 
 	fw->dvfs_mode = dvfs_mode;
 
-	ivpu_pm_schedule_recovery(vdev);
+	ret = pci_try_reset_function(to_pci_dev(vdev->drm.dev));
+	if (ret)
+		return ret;
 
 	return size;
 }
@@ -190,7 +192,10 @@ fw_profiling_freq_fops_write(struct file *file, const char __user *user_buf,
 		return ret;
 
 	ivpu_hw_profiling_freq_drive(vdev, enable);
-	ivpu_pm_schedule_recovery(vdev);
+
+	ret = pci_try_reset_function(to_pci_dev(vdev->drm.dev));
+	if (ret)
+		return ret;
 
 	return size;
 }
@@ -301,11 +306,18 @@ static ssize_t
 ivpu_force_recovery_fn(struct file *file, const char __user *user_buf, size_t size, loff_t *pos)
 {
 	struct ivpu_device *vdev = file->private_data;
+	int ret;
 
 	if (!size)
 		return -EINVAL;
 
-	ivpu_pm_schedule_recovery(vdev);
+	ret = ivpu_rpm_get(vdev);
+	if (ret)
+		return ret;
+
+	ivpu_pm_trigger_recovery(vdev, "debugfs");
+	flush_work(&vdev->pm->recovery_work);
+	ivpu_rpm_put(vdev);
 	return size;
 }
 

drivers/accel/ivpu/ivpu_hw_37xx.c

@@ -875,24 +875,18 @@ static void ivpu_hw_37xx_irq_disable(struct ivpu_device *vdev)
 
 static void ivpu_hw_37xx_irq_wdt_nce_handler(struct ivpu_device *vdev)
 {
-	ivpu_err_ratelimited(vdev, "WDT NCE irq\n");
-
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "WDT NCE IRQ");
 }
 
 static void ivpu_hw_37xx_irq_wdt_mss_handler(struct ivpu_device *vdev)
 {
-	ivpu_err_ratelimited(vdev, "WDT MSS irq\n");
-
 	ivpu_hw_wdt_disable(vdev);
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "WDT MSS IRQ");
 }
 
 static void ivpu_hw_37xx_irq_noc_firewall_handler(struct ivpu_device *vdev)
 {
-	ivpu_err_ratelimited(vdev, "NOC Firewall irq\n");
-
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "NOC Firewall IRQ");
 }
 
 /* Handler for IRQs from VPU core (irqV) */
@@ -970,7 +964,7 @@ static bool ivpu_hw_37xx_irqb_handler(struct ivpu_device *vdev, int irq)
 		REGB_WR32(VPU_37XX_BUTTRESS_INTERRUPT_STAT, status);
 
 	if (schedule_recovery)
-		ivpu_pm_schedule_recovery(vdev);
+		ivpu_pm_trigger_recovery(vdev, "Buttress IRQ");
 
 	return true;
 }

drivers/accel/ivpu/ivpu_hw_40xx.c

@@ -1049,18 +1049,18 @@ static void ivpu_hw_40xx_irq_disable(struct ivpu_device *vdev)
 static void ivpu_hw_40xx_irq_wdt_nce_handler(struct ivpu_device *vdev)
 {
 	/* TODO: For LNN hang consider engine reset instead of full recovery */
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "WDT NCE IRQ");
 }
 
 static void ivpu_hw_40xx_irq_wdt_mss_handler(struct ivpu_device *vdev)
 {
 	ivpu_hw_wdt_disable(vdev);
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "WDT MSS IRQ");
 }
 
 static void ivpu_hw_40xx_irq_noc_firewall_handler(struct ivpu_device *vdev)
 {
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "NOC Firewall IRQ");
 }
 
 /* Handler for IRQs from VPU core (irqV) */
@@ -1154,7 +1154,7 @@ static bool ivpu_hw_40xx_irqb_handler(struct ivpu_device *vdev, int irq)
 	REGB_WR32(VPU_40XX_BUTTRESS_INTERRUPT_STAT, status);
 
 	if (schedule_recovery)
-		ivpu_pm_schedule_recovery(vdev);
+		ivpu_pm_trigger_recovery(vdev, "Buttress IRQ");
 
 	return true;
 }

drivers/accel/ivpu/ivpu_ipc.c

@@ -343,10 +343,8 @@ int ivpu_ipc_send_receive_active(struct ivpu_device *vdev, struct vpu_jsm_msg *r
 	hb_ret = ivpu_ipc_send_receive_internal(vdev, &hb_req, VPU_JSM_MSG_QUERY_ENGINE_HB_DONE,
 						&hb_resp, VPU_IPC_CHAN_ASYNC_CMD,
 						vdev->timeout.jsm);
-	if (hb_ret == -ETIMEDOUT) {
-		ivpu_hw_diagnose_failure(vdev);
-		ivpu_pm_schedule_recovery(vdev);
-	}
+	if (hb_ret == -ETIMEDOUT)
+		ivpu_pm_trigger_recovery(vdev, "IPC timeout");
 
 	return ret;
 }

drivers/accel/ivpu/ivpu_job.c

@@ -515,7 +515,9 @@ int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 		goto err_destroy_job;
 	}
 
+	down_read(&vdev->pm->reset_lock);
 	ret = ivpu_job_submit(job);
+	up_read(&vdev->pm->reset_lock);
 	if (ret)
 		goto err_signal_fence;
 

drivers/accel/ivpu/ivpu_mmu.c

@@ -887,7 +887,6 @@ static u32 *ivpu_mmu_get_event(struct ivpu_device *vdev)
 
 void ivpu_mmu_irq_evtq_handler(struct ivpu_device *vdev)
 {
-	bool schedule_recovery = false;
 	u32 *event;
 	u32 ssid;
 
@@ -897,14 +896,13 @@ void ivpu_mmu_irq_evtq_handler(struct ivpu_device *vdev)
 		ivpu_mmu_dump_event(vdev, event);
 
 		ssid = FIELD_GET(IVPU_MMU_EVT_SSID_MASK, event[0]);
-		if (ssid == IVPU_GLOBAL_CONTEXT_MMU_SSID)
-			schedule_recovery = true;
-		else
-			ivpu_mmu_user_context_mark_invalid(vdev, ssid);
-	}
+		if (ssid == IVPU_GLOBAL_CONTEXT_MMU_SSID) {
+			ivpu_pm_trigger_recovery(vdev, "MMU event");
+			return;
+		}
 
-	if (schedule_recovery)
-		ivpu_pm_schedule_recovery(vdev);
+		ivpu_mmu_user_context_mark_invalid(vdev, ssid);
+	}
 }
 
 void ivpu_mmu_evtq_dump(struct ivpu_device *vdev)

drivers/accel/ivpu/ivpu_pm.c

@@ -112,6 +112,14 @@ static void ivpu_pm_recovery_work(struct work_struct *work)
 	char *evt[2] = {"IVPU_PM_EVENT=IVPU_RECOVER", NULL};
 	int ret;
 
+	ivpu_err(vdev, "Recovering the VPU (reset #%d)\n", atomic_read(&vdev->pm->reset_counter));
+
+	ret = pm_runtime_resume_and_get(vdev->drm.dev);
+	if (ret)
+		ivpu_err(vdev, "Failed to resume VPU: %d\n", ret);
+
+	ivpu_fw_log_dump(vdev);
+
 retry:
 	ret = pci_try_reset_function(to_pci_dev(vdev->drm.dev));
 	if (ret == -EAGAIN && !drm_dev_is_unplugged(&vdev->drm)) {
@@ -123,11 +131,13 @@ retry:
 		ivpu_err(vdev, "Failed to reset VPU: %d\n", ret);
 
 	kobject_uevent_env(&vdev->drm.dev->kobj, KOBJ_CHANGE, evt);
+	pm_runtime_mark_last_busy(vdev->drm.dev);
+	pm_runtime_put_autosuspend(vdev->drm.dev);
 }
 
-void ivpu_pm_schedule_recovery(struct ivpu_device *vdev)
+void ivpu_pm_trigger_recovery(struct ivpu_device *vdev, const char *reason)
 {
-	struct ivpu_pm_info *pm = vdev->pm;
+	ivpu_err(vdev, "Recovery triggered by %s\n", reason);
 
 	if (ivpu_disable_recovery) {
 		ivpu_err(vdev, "Recovery not available when disable_recovery param is set\n");
@@ -139,10 +149,11 @@ void ivpu_pm_schedule_recovery(struct ivpu_device *vdev)
 		return;
 	}
 
-	/* Schedule recovery if it's not in progress */
-	if (atomic_cmpxchg(&pm->in_reset, 0, 1) == 0) {
-		ivpu_hw_irq_disable(vdev);
-		queue_work(system_long_wq, &pm->recovery_work);
+	/* Trigger recovery if it's not in progress */
+	if (atomic_cmpxchg(&vdev->pm->reset_pending, 0, 1) == 0) {
+		ivpu_hw_diagnose_failure(vdev);
+		ivpu_hw_irq_disable(vdev); /* Disable IRQ early to protect from IRQ storm */
+		queue_work(system_long_wq, &vdev->pm->recovery_work);
 	}
 }
 
@@ -150,12 +161,8 @@ static void ivpu_job_timeout_work(struct work_struct *work)
 {
 	struct ivpu_pm_info *pm = container_of(work, struct ivpu_pm_info, job_timeout_work.work);
 	struct ivpu_device *vdev = pm->vdev;
-	unsigned long timeout_ms = ivpu_tdr_timeout_ms ? ivpu_tdr_timeout_ms : vdev->timeout.tdr;
 
-	ivpu_err(vdev, "TDR detected, timeout %lu ms", timeout_ms);
-	ivpu_hw_diagnose_failure(vdev);
-
-	ivpu_pm_schedule_recovery(vdev);
+	ivpu_pm_trigger_recovery(vdev, "TDR");
 }
 
 void ivpu_start_job_timeout_detection(struct ivpu_device *vdev)
@@ -228,6 +235,9 @@ int ivpu_pm_runtime_suspend_cb(struct device *dev)
 	bool hw_is_idle = true;
 	int ret;
 
+	drm_WARN_ON(&vdev->drm, !xa_empty(&vdev->submitted_jobs_xa));
+	drm_WARN_ON(&vdev->drm, work_pending(&vdev->pm->recovery_work));
+
 	ivpu_dbg(vdev, PM, "Runtime suspend..\n");
 
 	if (!ivpu_hw_is_idle(vdev) && vdev->pm->suspend_reschedule_counter) {
@@ -310,11 +320,12 @@ void ivpu_pm_reset_prepare_cb(struct pci_dev *pdev)
 {
 	struct ivpu_device *vdev = pci_get_drvdata(pdev);
 
-	pm_runtime_get_sync(vdev->drm.dev);
-
 	ivpu_dbg(vdev, PM, "Pre-reset..\n");
 	atomic_inc(&vdev->pm->reset_counter);
-	atomic_set(&vdev->pm->in_reset, 1);
+	atomic_set(&vdev->pm->reset_pending, 1);
+
+	pm_runtime_get_sync(vdev->drm.dev);
+	down_write(&vdev->pm->reset_lock);
 	ivpu_prepare_for_reset(vdev);
 	ivpu_hw_reset(vdev);
 	ivpu_pm_prepare_cold_boot(vdev);
@@ -331,9 +342,11 @@ void ivpu_pm_reset_done_cb(struct pci_dev *pdev)
 	ret = ivpu_resume(vdev);
 	if (ret)
 		ivpu_err(vdev, "Failed to set RESUME state: %d\n", ret);
-	atomic_set(&vdev->pm->in_reset, 0);
+	up_write(&vdev->pm->reset_lock);
+	atomic_set(&vdev->pm->reset_pending, 0);
 	ivpu_dbg(vdev, PM, "Post-reset done.\n");
 
+	pm_runtime_mark_last_busy(vdev->drm.dev);
 	pm_runtime_put_autosuspend(vdev->drm.dev);
 }
 
@@ -346,7 +359,10 @@ void ivpu_pm_init(struct ivpu_device *vdev)
 	pm->vdev = vdev;
 	pm->suspend_reschedule_counter = PM_RESCHEDULE_LIMIT;
 
-	atomic_set(&pm->in_reset, 0);
+	init_rwsem(&pm->reset_lock);
+	atomic_set(&pm->reset_pending, 0);
+	atomic_set(&pm->reset_counter, 0);
+
 	INIT_WORK(&pm->recovery_work, ivpu_pm_recovery_work);
 	INIT_DELAYED_WORK(&pm->job_timeout_work, ivpu_job_timeout_work);
 

drivers/accel/ivpu/ivpu_pm.h

@@ -6,6 +6,7 @@
 #ifndef __IVPU_PM_H__
 #define __IVPU_PM_H__
 
+#include <linux/rwsem.h>
 #include <linux/types.h>
 
 struct ivpu_device;
@@ -14,8 +15,9 @@ struct ivpu_pm_info {
 	struct ivpu_device *vdev;
 	struct delayed_work job_timeout_work;
 	struct work_struct recovery_work;
-	atomic_t in_reset;
+	struct rw_semaphore reset_lock;
 	atomic_t reset_counter;
+	atomic_t reset_pending;
 	bool is_warmboot;
 	u32 suspend_reschedule_counter;
 };
@@ -37,7 +39,7 @@ int __must_check ivpu_rpm_get(struct ivpu_device *vdev);
 int __must_check ivpu_rpm_get_if_active(struct ivpu_device *vdev);
 void ivpu_rpm_put(struct ivpu_device *vdev);
 
-void ivpu_pm_schedule_recovery(struct ivpu_device *vdev);
+void ivpu_pm_trigger_recovery(struct ivpu_device *vdev, const char *reason);
 void ivpu_start_job_timeout_detection(struct ivpu_device *vdev);
 void ivpu_stop_job_timeout_detection(struct ivpu_device *vdev);