dmaengine: idxd: support reporting of halt interrupt

Unmask the halt error interrupt so it gets reported to the interrupt
handler. When halt state interrupt is received, quiesce the kernel
WQs and unmap the portals to stop submission.

Signed-off-by: Dave Jiang <[email protected]>
Link: https://lore.kernel.org/r/161894441167.3202472.9485946398140619501.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <[email protected]>

Author: davejiang

drivers/dma/idxd/device.c

@@ -47,6 +47,7 @@ void idxd_unmask_error_interrupts(struct idxd_device *idxd)
 
 	genctrl.bits = ioread32(idxd->reg_base + IDXD_GENCTRL_OFFSET);
 	genctrl.softerr_int_en = 1;
+	genctrl.halt_int_en = 1;
 	iowrite32(genctrl.bits, idxd->reg_base + IDXD_GENCTRL_OFFSET);
 }
 
@@ -56,6 +57,7 @@ void idxd_mask_error_interrupts(struct idxd_device *idxd)
 
 	genctrl.bits = ioread32(idxd->reg_base + IDXD_GENCTRL_OFFSET);
 	genctrl.softerr_int_en = 0;
+	genctrl.halt_int_en = 0;
 	iowrite32(genctrl.bits, idxd->reg_base + IDXD_GENCTRL_OFFSET);
 }
 
@@ -312,6 +314,19 @@ void idxd_wq_unmap_portal(struct idxd_wq *wq)
 	struct device *dev = &wq->idxd->pdev->dev;
 
 	devm_iounmap(dev, wq->portal);
+	wq->portal = NULL;
+}
+
+void idxd_wqs_unmap_portal(struct idxd_device *idxd)
+{
+	int i;
+
+	for (i = 0; i < idxd->max_wqs; i++) {
+		struct idxd_wq *wq = idxd->wqs[i];
+
+		if (wq->portal)
+			idxd_wq_unmap_portal(wq);
+	}
 }
 
 int idxd_wq_set_pasid(struct idxd_wq *wq, int pasid)

drivers/dma/idxd/idxd.h

@@ -371,6 +371,7 @@ int idxd_register_devices(struct idxd_device *idxd);
 void idxd_unregister_devices(struct idxd_device *idxd);
 int idxd_register_driver(void);
 void idxd_unregister_driver(void);
+void idxd_wqs_quiesce(struct idxd_device *idxd);
 
 /* device interrupt control */
 void idxd_msix_perm_setup(struct idxd_device *idxd);
@@ -400,6 +401,7 @@ int idxd_device_release_int_handle(struct idxd_device *idxd, int handle,
 				   enum idxd_interrupt_type irq_type);
 
 /* work queue control */
+void idxd_wqs_unmap_portal(struct idxd_device *idxd);
 int idxd_wq_alloc_resources(struct idxd_wq *wq);
 void idxd_wq_free_resources(struct idxd_wq *wq);
 int idxd_wq_enable(struct idxd_wq *wq);

drivers/dma/idxd/init.c

@@ -647,6 +647,18 @@ static void idxd_flush_work_list(struct idxd_irq_entry *ie)
 	}
 }
 
+void idxd_wqs_quiesce(struct idxd_device *idxd)
+{
+	struct idxd_wq *wq;
+	int i;
+
+	for (i = 0; i < idxd->max_wqs; i++) {
+		wq = idxd->wqs[i];
+		if (wq->state == IDXD_WQ_ENABLED && wq->type == IDXD_WQT_KERNEL)
+			idxd_wq_quiesce(wq);
+	}
+}
+
 static void idxd_release_int_handles(struct idxd_device *idxd)
 {
 	struct device *dev = &idxd->pdev->dev;

drivers/dma/idxd/irq.c

@@ -202,6 +202,8 @@ static int process_misc_interrupts(struct idxd_device *idxd, u32 cause)
 			queue_work(idxd->wq, &idxd->work);
 		} else {
 			spin_lock_bh(&idxd->dev_lock);
+			idxd_wqs_quiesce(idxd);
+			idxd_wqs_unmap_portal(idxd);
 			idxd_device_wqs_clear_state(idxd);
 			dev_err(&idxd->pdev->dev,
 				"idxd halted, need %s.\n",

drivers/dma/idxd/registers.h

@@ -120,7 +120,8 @@ union gencfg_reg {
 union genctrl_reg {
 	struct {
 		u32 softerr_int_en:1;
-		u32 rsvd:31;
+		u32 halt_int_en:1;
+		u32 rsvd:30;
 	};
 	u32 bits;
 } __packed;