habanalabs: add reset support when user closes FD

In order to support command submissions that are done directly from
user space, the driver must perform soft reset once user closes its FD.
In case the soft reset fails or device is not idle, a hard reset should
be performed.
Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

drivers/misc/habanalabs/common/device.c

@@ -103,8 +103,24 @@ static int hl_device_release(struct inode *inode, struct file *filp)
 		return 0;
 	}
 
-	hl_cb_mgr_fini(hpriv->hdev, &hpriv->cb_mgr);
-	hl_ctx_mgr_fini(hpriv->hdev, &hpriv->ctx_mgr);
+	hl_cb_mgr_fini(hdev, &hpriv->cb_mgr);
+	hl_ctx_mgr_fini(hdev, &hpriv->ctx_mgr);
+
+	if (hdev->reset_upon_device_release) {
+		u64 idle_mask[HL_BUSY_ENGINES_MASK_EXT_SIZE] = {0};
+
+		/* We try soft reset first */
+		hl_device_reset(hdev, false, false);
+
+		/* If device is not idle perform hard reset */
+		if (!hdev->asic_funcs->is_device_idle(hdev, idle_mask,
+				HL_BUSY_ENGINES_MASK_EXT_SIZE, NULL)) {
+			dev_info(hdev->dev,
+				"device is not idle (mask %#llx %#llx) after soft reset, performing hard reset",
+				idle_mask[0], idle_mask[1]);
+			hl_device_reset(hdev, true, false);
+		}
+	}
 
 	hl_hpriv_put(hpriv);
 

drivers/misc/habanalabs/common/habanalabs.h

@@ -1920,6 +1920,7 @@ struct hl_mmu_funcs {
  * @device_fini_pending: true if device_fini was called and might be
  *                       waiting for the reset thread to finish
  * @supports_staged_submission: true if staged submissions are supported
+ * @reset_upon_device_release: true if reset is required upon device release
  */
 struct hl_device {
 	struct pci_dev			*pdev;
@@ -2026,6 +2027,7 @@ struct hl_device {
 	u8				process_kill_trial_cnt;
 	u8				device_fini_pending;
 	u8				supports_staged_submission;
+	u8				reset_upon_device_release;
 
 	/* Parameters for bring-up */
 	u64				nic_ports_mask;