1 files changed, 137 insertions, 10 deletions

diff --git a/drivers/gpu/drm/imagination/pvr_device.c b/drivers/gpu/drm/imagination/pvr_device.c
index 1704c0268589..8b9ba4983c4c 100644
--- a/drivers/gpu/drm/imagination/pvr_device.c
+++ b/drivers/gpu/drm/imagination/pvr_device.c
@@ -25,6 +25,7 @@
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
@@ -120,6 +121,21 @@ static int pvr_device_clk_init(struct pvr_device *pvr_dev)
 	return 0;
 }
 
+static int pvr_device_reset_init(struct pvr_device *pvr_dev)
+{
+	struct drm_device *drm_dev = from_pvr_device(pvr_dev);
+	struct reset_control *reset;
+
+	reset = devm_reset_control_get_optional_exclusive(drm_dev->dev, NULL);
+	if (IS_ERR(reset))
+		return dev_err_probe(drm_dev->dev, PTR_ERR(reset),
+				     "failed to get gpu reset line\n");
+
+	pvr_dev->reset = reset;
+
+	return 0;
+}
+
 /**
  * pvr_device_process_active_queues() - Process all queue related events.
  * @pvr_dev: PowerVR device to check
@@ -146,9 +162,61 @@ static void pvr_device_process_active_queues(struct pvr_device *pvr_dev)
 	mutex_unlock(&pvr_dev->queues.lock);
 }
 
+static bool pvr_device_safety_irq_pending(struct pvr_device *pvr_dev)
+{
+	u32 events;
+
+	WARN_ON_ONCE(!pvr_dev->has_safety_events);
+
+	events = pvr_cr_read32(pvr_dev, ROGUE_CR_EVENT_STATUS);
+
+	return (events & ROGUE_CR_EVENT_STATUS_SAFETY_EN) != 0;
+}
+
+static void pvr_device_safety_irq_clear(struct pvr_device *pvr_dev)
+{
+	WARN_ON_ONCE(!pvr_dev->has_safety_events);
+
+	pvr_cr_write32(pvr_dev, ROGUE_CR_EVENT_CLEAR,
+		       ROGUE_CR_EVENT_CLEAR_SAFETY_EN);
+}
+
+static void pvr_device_handle_safety_events(struct pvr_device *pvr_dev)
+{
+	struct drm_device *drm_dev = from_pvr_device(pvr_dev);
+	u32 events;
+
+	WARN_ON_ONCE(!pvr_dev->has_safety_events);
+
+	events = pvr_cr_read32(pvr_dev, ROGUE_CR_SAFETY_EVENT_STATUS__ROGUEXE);
+
+	/* Handle only these events on the host and leave the rest to the FW. */
+	events &= ROGUE_CR_SAFETY_EVENT_STATUS__ROGUEXE__FAULT_FW_EN |
+		ROGUE_CR_SAFETY_EVENT_STATUS__ROGUEXE__WATCHDOG_TIMEOUT_EN;
+
+	pvr_cr_write32(pvr_dev, ROGUE_CR_SAFETY_EVENT_CLEAR__ROGUEXE, events);
+
+	if (events & ROGUE_CR_SAFETY_EVENT_STATUS__ROGUEXE__FAULT_FW_EN) {
+		u32 fault_fw = pvr_cr_read32(pvr_dev, ROGUE_CR_FAULT_FW_STATUS);
+
+		pvr_cr_write32(pvr_dev, ROGUE_CR_FAULT_FW_CLEAR, fault_fw);
+
+		drm_info(drm_dev, "Safety event: FW fault (mask=0x%08x)\n", fault_fw);
+	}
+
+	if (events & ROGUE_CR_SAFETY_EVENT_STATUS__ROGUEXE__WATCHDOG_TIMEOUT_EN) {
+		/*
+		 * The watchdog timer is disabled by the driver so this event
+		 * should never be fired.
+		 */
+		drm_info(drm_dev, "Safety event: Watchdog timeout\n");
+	}
+}
+
 static irqreturn_t pvr_device_irq_thread_handler(int irq, void *data)
 {
 	struct pvr_device *pvr_dev = data;
+	struct drm_device *drm_dev = from_pvr_device(pvr_dev);
 	irqreturn_t ret = IRQ_NONE;
 
 	/* We are in the threaded handler, we can keep dequeuing events until we
@@ -164,30 +232,76 @@ static irqreturn_t pvr_device_irq_thread_handler(int irq, void *data)
 			pvr_device_process_active_queues(pvr_dev);
 		}
 
-		pm_runtime_mark_last_busy(from_pvr_device(pvr_dev)->dev);
+		pm_runtime_mark_last_busy(drm_dev->dev);
 
 		ret = IRQ_HANDLED;
 	}
 
-	/* Unmask FW irqs before returning, so new interrupts can be received. */
-	pvr_fw_irq_enable(pvr_dev);
+	if (pvr_dev->has_safety_events) {
+		int err;
+
+		/*
+		 * Ensure the GPU is powered on since some safety events (such
+		 * as ECC faults) can happen outside of job submissions, which
+		 * are otherwise the only time a power reference is held.
+		 */
+		err = pvr_power_get(pvr_dev);
+		if (err) {
+			drm_err_ratelimited(drm_dev,
+					    "%s: could not take power reference (%d)\n",
+					    __func__, err);
+			return ret;
+		}
+
+		while (pvr_device_safety_irq_pending(pvr_dev)) {
+			pvr_device_safety_irq_clear(pvr_dev);
+			pvr_device_handle_safety_events(pvr_dev);
+
+			ret = IRQ_HANDLED;
+		}
+
+		pvr_power_put(pvr_dev);
+	}
+
 	return ret;
 }
 
 static irqreturn_t pvr_device_irq_handler(int irq, void *data)
 {
 	struct pvr_device *pvr_dev = data;
+	bool safety_irq_pending = false;
+
+	if (pvr_dev->has_safety_events)
+		safety_irq_pending = pvr_device_safety_irq_pending(pvr_dev);
 
-	if (!pvr_fw_irq_pending(pvr_dev))
+	if (!pvr_fw_irq_pending(pvr_dev) && !safety_irq_pending)
 		return IRQ_NONE; /* Spurious IRQ - ignore. */
 
-	/* Mask the FW interrupts before waking up the thread. Will be unmasked
-	 * when the thread handler is done processing events.
-	 */
-	pvr_fw_irq_disable(pvr_dev);
 	return IRQ_WAKE_THREAD;
 }
 
+static void pvr_device_safety_irq_init(struct pvr_device *pvr_dev)
+{
+	u32 num_ecc_rams = 0;
+
+	/*
+	 * Safety events are an optional feature of the RogueXE platform. They
+	 * are only enabled if at least one of ECC memory or the watchdog timer
+	 * are present in HW. While safety events can be generated by other
+	 * systems, that will never happen if the above mentioned hardware is
+	 * not present.
+	 */
+	if (!PVR_HAS_FEATURE(pvr_dev, roguexe)) {
+		pvr_dev->has_safety_events = false;
+		return;
+	}
+
+	PVR_FEATURE_VALUE(pvr_dev, ecc_rams, &num_ecc_rams);
+
+	pvr_dev->has_safety_events =
+		num_ecc_rams > 0 || PVR_HAS_FEATURE(pvr_dev, watchdog_timer);
+}
+
 /**
  * pvr_device_irq_init() - Initialise IRQ required by a PowerVR device
  * @pvr_dev: Target PowerVR device.
@@ -205,17 +319,25 @@ pvr_device_irq_init(struct pvr_device *pvr_dev)
 
 	init_waitqueue_head(&pvr_dev->kccb.rtn_q);
 
+	pvr_device_safety_irq_init(pvr_dev);
+
 	pvr_dev->irq = platform_get_irq(plat_dev, 0);
 	if (pvr_dev->irq < 0)
 		return pvr_dev->irq;
 
 	/* Clear any pending events before requesting the IRQ line. */
 	pvr_fw_irq_clear(pvr_dev);
-	pvr_fw_irq_enable(pvr_dev);
 
+	if (pvr_dev->has_safety_events)
+		pvr_device_safety_irq_clear(pvr_dev);
+
+	/*
+	 * The ONESHOT flag ensures IRQs are masked while the thread handler is
+	 * running.
+	 */
 	return request_threaded_irq(pvr_dev->irq, pvr_device_irq_handler,
 				    pvr_device_irq_thread_handler,
-				    IRQF_SHARED, "gpu", pvr_dev);
+				    IRQF_SHARED | IRQF_ONESHOT, "gpu", pvr_dev);
 }
 
 /**
@@ -509,6 +631,11 @@ pvr_device_init(struct pvr_device *pvr_dev)
 	if (err)
 		return err;
 
+	/* Get the reset line for the GPU */
+	err = pvr_device_reset_init(pvr_dev);
+	if (err)
+		return err;
+
 	/* Explicitly power the GPU so we can access control registers before the FW is booted. */
 	err = pm_runtime_resume_and_get(dev);
 	if (err)