gve: Deprecate adminq_pfn for pci revision 0x1.

adminq_pfn assumes a page size of 4k, causing this mechanism to break in
kernels compiled with different page sizes. A new PCI device revision was
needed for the device to be able to communicate with the driver how to
set up the admin queue prior to having access to the admin queue.

Signed-off-by: Jordan Kimbrough <jrkim@google.com>
Signed-off-by: John Fraker <jfraker@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231128002648.320892-3-jfraker@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/google/gve/gve_adminq.c

@@ -225,9 +225,20 @@ int gve_adminq_alloc(struct device *dev, struct gve_priv *priv)
 	priv->adminq_get_ptype_map_cnt = 0;
 
 	/* Setup Admin queue with the device */
-	iowrite32be(priv->adminq_bus_addr / PAGE_SIZE,
-		    &priv->reg_bar0->adminq_pfn);
-
+	if (priv->pdev->revision < 0x1) {
+		iowrite32be(priv->adminq_bus_addr / PAGE_SIZE,
+			    &priv->reg_bar0->adminq_pfn);
+	} else {
+		iowrite16be(GVE_ADMINQ_BUFFER_SIZE,
+			    &priv->reg_bar0->adminq_length);
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+		iowrite32be(priv->adminq_bus_addr >> 32,
+			    &priv->reg_bar0->adminq_base_address_hi);
+#endif
+		iowrite32be(priv->adminq_bus_addr,
+			    &priv->reg_bar0->adminq_base_address_lo);
+		iowrite32be(GVE_DRIVER_STATUS_RUN_MASK, &priv->reg_bar0->driver_status);
+	}
 	gve_set_admin_queue_ok(priv);
 	return 0;
 }
@@ -237,16 +248,27 @@ void gve_adminq_release(struct gve_priv *priv)
 	int i = 0;
 
 	/* Tell the device the adminq is leaving */
-	iowrite32be(0x0, &priv->reg_bar0->adminq_pfn);
-	while (ioread32be(&priv->reg_bar0->adminq_pfn)) {
-		/* If this is reached the device is unrecoverable and still
-		 * holding memory. Continue looping to avoid memory corruption,
-		 * but WARN so it is visible what is going on.
-		 */
-		if (i == GVE_MAX_ADMINQ_RELEASE_CHECK)
-			WARN(1, "Unrecoverable platform error!");
-		i++;
-		msleep(GVE_ADMINQ_SLEEP_LEN);
+	if (priv->pdev->revision < 0x1) {
+		iowrite32be(0x0, &priv->reg_bar0->adminq_pfn);
+		while (ioread32be(&priv->reg_bar0->adminq_pfn)) {
+			/* If this is reached the device is unrecoverable and still
+			 * holding memory. Continue looping to avoid memory corruption,
+			 * but WARN so it is visible what is going on.
+			 */
+			if (i == GVE_MAX_ADMINQ_RELEASE_CHECK)
+				WARN(1, "Unrecoverable platform error!");
+			i++;
+			msleep(GVE_ADMINQ_SLEEP_LEN);
+		}
+	} else {
+		iowrite32be(GVE_DRIVER_STATUS_RESET_MASK, &priv->reg_bar0->driver_status);
+		while (!(ioread32be(&priv->reg_bar0->device_status)
+				& GVE_DEVICE_STATUS_DEVICE_IS_RESET)) {
+			if (i == GVE_MAX_ADMINQ_RELEASE_CHECK)
+				WARN(1, "Unrecoverable platform error!");
+			i++;
+			msleep(GVE_ADMINQ_SLEEP_LEN);
+		}
 	}
 	gve_clear_device_rings_ok(priv);
 	gve_clear_device_resources_ok(priv);

drivers/net/ethernet/google/gve/gve_register.h

@@ -18,11 +18,20 @@ struct gve_registers {
 	__be32	adminq_event_counter;
 	u8	reserved[3];
 	u8	driver_version;
+	__be32	adminq_base_address_hi;
+	__be32	adminq_base_address_lo;
+	__be16	adminq_length;
 };
 
 enum gve_device_status_flags {
 	GVE_DEVICE_STATUS_RESET_MASK		= BIT(1),
 	GVE_DEVICE_STATUS_LINK_STATUS_MASK	= BIT(2),
 	GVE_DEVICE_STATUS_REPORT_STATS_MASK	= BIT(3),
+	GVE_DEVICE_STATUS_DEVICE_IS_RESET	= BIT(4),
+};
+
+enum gve_driver_status_flags {
+	GVE_DRIVER_STATUS_RUN_MASK		= BIT(0),
+	GVE_DRIVER_STATUS_RESET_MASK		= BIT(1),
 };
 #endif /* _GVE_REGISTER_H_ */