accel/habanalabs: add handling for unexpected user event

In order for the user to be aware of unexpected events in Gaudi2 that
aren't assigned to a specific engine, we are adding the handling of
this dedicated interrupt.
Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

drivers/accel/habanalabs/common/habanalabs.h

@@ -662,6 +662,7 @@ struct hl_hints_range {
  * @user_interrupt_count: number of user interrupts.
  * @user_dec_intr_count: number of decoder interrupts exposed to user.
  * @tpc_interrupt_id: interrupt id for TPC to use in order to raise events towards the host.
+ * @unexpected_user_error_interrupt_id: interrupt id used to indicate an unexpected user error.
  * @cache_line_size: device cache line size.
  * @server_type: Server type that the ASIC is currently installed in.
  *               The value is according to enum hl_server_type in uapi file.
@@ -792,6 +793,7 @@ struct asic_fixed_properties {
 	u16				user_interrupt_count;
 	u16				user_dec_intr_count;
 	u16				tpc_interrupt_id;
+	u16				unexpected_user_error_interrupt_id;
 	u16				cache_line_size;
 	u16				server_type;
 	u8				completion_queues_count;
@@ -1101,7 +1103,8 @@ struct hl_cq {
 enum hl_user_interrupt_type {
 	HL_USR_INTERRUPT_CQ = 0,
 	HL_USR_INTERRUPT_DECODER,
-	HL_USR_INTERRUPT_TPC
+	HL_USR_INTERRUPT_TPC,
+	HL_USR_INTERRUPT_UNEXPECTED
 };
 
 /**
@@ -3155,6 +3158,7 @@ struct hl_reset_info {
  *                  interrupt, driver will monitor the list of fences
  *                  registered to this interrupt.
  * @tpc_interrupt: single TPC interrupt for all TPCs.
+ * @unexpected_error_interrupt: single interrupt for unexpected user error indication.
  * @common_user_cq_interrupt: common user CQ interrupt for all user CQ interrupts.
  *                         upon any user CQ interrupt, driver will monitor the
  *                         list of fences registered to this common structure.
@@ -3340,6 +3344,7 @@ struct hl_device {
 	struct hl_cq			*completion_queue;
 	struct hl_user_interrupt	*user_interrupt;
 	struct hl_user_interrupt	tpc_interrupt;
+	struct hl_user_interrupt	unexpected_error_interrupt;
 	struct hl_user_interrupt	common_user_cq_interrupt;
 	struct hl_user_interrupt	common_decoder_interrupt;
 	struct hl_cs			**shadow_cs_queue;

drivers/accel/habanalabs/common/irq.c

@@ -340,6 +340,11 @@ static void handle_tpc_interrupt(struct hl_device *hdev)
 	hl_device_cond_reset(hdev, flags, event_mask);
 }
 
+static void handle_unexpected_user_interrupt(struct hl_device *hdev)
+{
+	dev_err_ratelimited(hdev->dev, "Received unexpected user error interrupt\n");
+}
+
 /**
  * hl_irq_handler_user_interrupt - irq handler for user interrupts
  *
@@ -385,6 +390,9 @@ irqreturn_t hl_irq_user_interrupt_thread_handler(int irq, void *arg)
 	case HL_USR_INTERRUPT_TPC:
 		handle_tpc_interrupt(hdev);
 		break;
+	case HL_USR_INTERRUPT_UNEXPECTED:
+		handle_unexpected_user_interrupt(hdev);
+		break;
 	default:
 		break;
 	}

drivers/accel/habanalabs/gaudi2/gaudi2.c

@@ -2440,6 +2440,7 @@ static int gaudi2_set_fixed_properties(struct hl_device *hdev)
 
 	prop->first_available_user_interrupt = GAUDI2_IRQ_NUM_USER_FIRST;
 	prop->tpc_interrupt_id = GAUDI2_IRQ_NUM_TPC_ASSERT;
+	prop->unexpected_user_error_interrupt_id = GAUDI2_IRQ_NUM_UNEXPECTED_ERROR;
 
 	prop->first_available_cq[0] = GAUDI2_RESERVED_CQ_NUMBER;
 
@@ -3346,6 +3347,10 @@ static void gaudi2_user_interrupt_setup(struct hl_device *hdev)
 	/* Initialize TPC interrupt */
 	HL_USR_INTR_STRUCT_INIT(hdev->tpc_interrupt, hdev, 0, HL_USR_INTERRUPT_TPC);
 
+	/* Initialize general purpose interrupt */
+	HL_USR_INTR_STRUCT_INIT(hdev->unexpected_error_interrupt, hdev, 0,
+						HL_USR_INTERRUPT_UNEXPECTED);
+
 	/* Initialize common user CQ interrupt */
 	HL_USR_INTR_STRUCT_INIT(hdev->common_user_cq_interrupt, hdev,
 				HL_COMMON_USER_CQ_INTERRUPT_ID, HL_USR_INTERRUPT_CQ);
@@ -4005,6 +4010,8 @@ static const char *gaudi2_irq_name(u16 irq_number)
 		return gaudi2_vdec_irq_name[irq_number - GAUDI2_IRQ_NUM_DCORE0_DEC0_NRM];
 	case GAUDI2_IRQ_NUM_TPC_ASSERT:
 		return "gaudi2 tpc assert";
+	case GAUDI2_IRQ_NUM_UNEXPECTED_ERROR:
+		return "gaudi2 tpc assert";
 	case GAUDI2_IRQ_NUM_USER_FIRST ... GAUDI2_IRQ_NUM_USER_LAST:
 		return "gaudi2 user completion";
 	default:
@@ -4125,6 +4132,15 @@ static int gaudi2_enable_msix(struct hl_device *hdev)
 		goto free_dec_irq;
 	}
 
+	irq = pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_UNEXPECTED_ERROR);
+	rc = request_irq(irq, hl_irq_handler_user_interrupt, 0,
+			gaudi2_irq_name(GAUDI2_IRQ_NUM_UNEXPECTED_ERROR),
+					&hdev->unexpected_error_interrupt);
+	if (rc) {
+		dev_err(hdev->dev, "Failed to request IRQ %d", irq);
+		goto free_tpc_irq;
+	}
+
 	for (i = GAUDI2_IRQ_NUM_USER_FIRST, j = prop->user_dec_intr_count, user_irq_init_cnt = 0;
 			user_irq_init_cnt < prop->user_interrupt_count;
 			i++, j++, user_irq_init_cnt++) {
@@ -4151,6 +4167,11 @@ static int gaudi2_enable_msix(struct hl_device *hdev)
 		irq = pci_irq_vector(hdev->pdev, i);
 		free_irq(irq, &hdev->user_interrupt[j]);
 	}
+	irq = pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_UNEXPECTED_ERROR);
+	free_irq(irq, &hdev->unexpected_error_interrupt);
+free_tpc_irq:
+	irq = pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_TPC_ASSERT);
+	free_irq(irq, &hdev->tpc_interrupt);
 free_dec_irq:
 	gaudi2_dec_disable_msix(hdev, GAUDI2_IRQ_NUM_DEC_LAST + 1);
 free_event_irq:
@@ -4185,6 +4206,7 @@ static void gaudi2_sync_irqs(struct hl_device *hdev)
 	}
 
 	synchronize_irq(pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_TPC_ASSERT));
+	synchronize_irq(pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_UNEXPECTED_ERROR));
 
 	for (i = GAUDI2_IRQ_NUM_USER_FIRST, j = 0 ; j < hdev->asic_prop.user_interrupt_count;
 										i++, j++) {
@@ -4215,6 +4237,9 @@ static void gaudi2_disable_msix(struct hl_device *hdev)
 	irq = pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_TPC_ASSERT);
 	free_irq(irq, &hdev->tpc_interrupt);
 
+	irq = pci_irq_vector(hdev->pdev, GAUDI2_IRQ_NUM_UNEXPECTED_ERROR);
+	free_irq(irq, &hdev->unexpected_error_interrupt);
+
 	for (i = GAUDI2_IRQ_NUM_USER_FIRST, j = prop->user_dec_intr_count, k = 0;
 			k < hdev->asic_prop.user_interrupt_count ; i++, j++, k++) {
 

drivers/accel/habanalabs/gaudi2/gaudi2P.h

@@ -387,6 +387,8 @@ enum gaudi2_edma_id {
  * We have 64 CQ's per dcore, CQ0 in dcore 0 is reserved for legacy mode
  */
 #define GAUDI2_NUM_USER_INTERRUPTS 255
+#define GAUDI2_NUM_RESERVED_INTERRUPTS 1
+#define GAUDI2_TOTAL_USER_INTERRUPTS (GAUDI2_NUM_USER_INTERRUPTS + GAUDI2_NUM_RESERVED_INTERRUPTS)
 
 enum gaudi2_irq_num {
 	GAUDI2_IRQ_NUM_EVENT_QUEUE = GAUDI2_EVENT_QUEUE_MSIX_IDX,
@@ -416,8 +418,9 @@ enum gaudi2_irq_num {
 	GAUDI2_IRQ_NUM_NIC_PORT_LAST = (GAUDI2_IRQ_NUM_NIC_PORT_FIRST + NIC_NUMBER_OF_PORTS - 1),
 	GAUDI2_IRQ_NUM_TPC_ASSERT,
 	GAUDI2_IRQ_NUM_RESERVED_FIRST,
-	GAUDI2_IRQ_NUM_RESERVED_LAST = (GAUDI2_MSIX_ENTRIES - GAUDI2_NUM_USER_INTERRUPTS - 1),
-	GAUDI2_IRQ_NUM_USER_FIRST,
+	GAUDI2_IRQ_NUM_RESERVED_LAST = (GAUDI2_MSIX_ENTRIES - GAUDI2_TOTAL_USER_INTERRUPTS - 1),
+	GAUDI2_IRQ_NUM_UNEXPECTED_ERROR = RESERVED_MSIX_UNEXPECTED_USER_ERROR_INTERRUPT,
+	GAUDI2_IRQ_NUM_USER_FIRST = GAUDI2_IRQ_NUM_UNEXPECTED_ERROR + 1,
 	GAUDI2_IRQ_NUM_USER_LAST = (GAUDI2_IRQ_NUM_USER_FIRST + GAUDI2_NUM_USER_INTERRUPTS - 1),
 	GAUDI2_IRQ_NUM_LAST = (GAUDI2_MSIX_ENTRIES - 1)
 };

drivers/accel/habanalabs/include/gaudi2/gaudi2.h

@@ -63,6 +63,8 @@
 #define RESERVED_VA_RANGE_FOR_ARC_ON_HOST_HPAGE_START	0xFFF0F80000000000ull
 #define RESERVED_VA_RANGE_FOR_ARC_ON_HOST_HPAGE_END	0xFFF0FFFFFFFFFFFFull
 
+#define RESERVED_MSIX_UNEXPECTED_USER_ERROR_INTERRUPT	256
+
 #define GAUDI2_MSIX_ENTRIES	512
 
 #define QMAN_PQ_ENTRY_SIZE	16			/* Bytes */