Merge branch 'enetc-probe-fix'

Vladimir Oltean says:

====================
Fix ENETC probing after 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")

I'm not sure who should take this patch set (net maintainers or PCI
maintainers). Everyone could pick up just their part, and that would
work (no compile time dependencies). However, the entire series needs
ACK from both sides and Rob for sure.

v1 at:
https://lore.kernel.org/netdev/20230521115141.2384444-1-vladimir.oltean@nxp.com/
====================

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 74 insertions, 46 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index 1416262d42967a..e0a4cb7e3f5017 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -1186,14 +1186,9 @@ static int enetc_init_port_rss_memory(struct enetc_si *si)
 
 static int enetc_pf_register_with_ierb(struct pci_dev *pdev)
 {
-	struct device_node *node = pdev->dev.of_node;
 	struct platform_device *ierb_pdev;
 	struct device_node *ierb_node;
 
-	/* Don't register with the IERB if the PF itself is disabled */
-	if (!node || !of_device_is_available(node))
-		return 0;
-
 	ierb_node = of_find_compatible_node(NULL, NULL,
 					    "fsl,ls1028a-enetc-ierb");
 	if (!ierb_node || !of_device_is_available(ierb_node))
@@ -1208,56 +1203,81 @@ static int enetc_pf_register_with_ierb(struct pci_dev *pdev)
 	return enetc_ierb_register_pf(ierb_pdev, pdev);
 }
 
-static int enetc_pf_probe(struct pci_dev *pdev,
-			  const struct pci_device_id *ent)
+static struct enetc_si *enetc_psi_create(struct pci_dev *pdev)
 {
-	struct device_node *node = pdev->dev.of_node;
-	struct enetc_ndev_priv *priv;
-	struct net_device *ndev;
 	struct enetc_si *si;
-	struct enetc_pf *pf;
 	int err;
 
-	err = enetc_pf_register_with_ierb(pdev);
-	if (err == -EPROBE_DEFER)
-		return err;
-	if (err)
-		dev_warn(&pdev->dev,
-			 "Could not register with IERB driver: %pe, please update the device tree\n",
-			 ERR_PTR(err));
-
-	err = enetc_pci_probe(pdev, KBUILD_MODNAME, sizeof(*pf));
-	if (err)
-		return dev_err_probe(&pdev->dev, err, "PCI probing failed\n");
+	err = enetc_pci_probe(pdev, KBUILD_MODNAME, sizeof(struct enetc_pf));
+	if (err) {
+		dev_err_probe(&pdev->dev, err, "PCI probing failed\n");
+		goto out;
+	}
 
 	si = pci_get_drvdata(pdev);
 	if (!si->hw.port || !si->hw.global) {
 		err = -ENODEV;
 		dev_err(&pdev->dev, "could not map PF space, probing a VF?\n");
-		goto err_map_pf_space;
+		goto out_pci_remove;
 	}
 
 	err = enetc_setup_cbdr(&pdev->dev, &si->hw, ENETC_CBDR_DEFAULT_SIZE,
 			       &si->cbd_ring);
 	if (err)
-		goto err_setup_cbdr;
+		goto out_pci_remove;
 
 	err = enetc_init_port_rfs_memory(si);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to initialize RFS memory\n");
-		goto err_init_port_rfs;
+		goto out_teardown_cbdr;
 	}
 
 	err = enetc_init_port_rss_memory(si);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to initialize RSS memory\n");
-		goto err_init_port_rss;
+		goto out_teardown_cbdr;
 	}
 
-	if (node && !of_device_is_available(node)) {
-		dev_info(&pdev->dev, "device is disabled, skipping\n");
-		err = -ENODEV;
-		goto err_device_disabled;
+	return si;
+
+out_teardown_cbdr:
+	enetc_teardown_cbdr(&si->cbd_ring);
+out_pci_remove:
+	enetc_pci_remove(pdev);
+out:
+	return ERR_PTR(err);
+}
+
+static void enetc_psi_destroy(struct pci_dev *pdev)
+{
+	struct enetc_si *si = pci_get_drvdata(pdev);
+
+	enetc_teardown_cbdr(&si->cbd_ring);
+	enetc_pci_remove(pdev);
+}
+
+static int enetc_pf_probe(struct pci_dev *pdev,
+			  const struct pci_device_id *ent)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct enetc_ndev_priv *priv;
+	struct net_device *ndev;
+	struct enetc_si *si;
+	struct enetc_pf *pf;
+	int err;
+
+	err = enetc_pf_register_with_ierb(pdev);
+	if (err == -EPROBE_DEFER)
+		return err;
+	if (err)
+		dev_warn(&pdev->dev,
+			 "Could not register with IERB driver: %pe, please update the device tree\n",
+			 ERR_PTR(err));
+
+	si = enetc_psi_create(pdev);
+	if (IS_ERR(si)) {
+		err = PTR_ERR(si);
+		goto err_psi_create;
 	}
 
 	pf = enetc_si_priv(si);
@@ -1339,15 +1359,9 @@ err_alloc_si_res:
 	si->ndev = NULL;
 	free_netdev(ndev);
 err_alloc_netdev:
-err_init_port_rss:
-err_init_port_rfs:
-err_device_disabled:
 err_setup_mac_addresses:
-	enetc_teardown_cbdr(&si->cbd_ring);
-err_setup_cbdr:
-err_map_pf_space:
-	enetc_pci_remove(pdev);
-
+	enetc_psi_destroy(pdev);
+err_psi_create:
 	return err;
 }
 
@@ -1370,12 +1384,29 @@ static void enetc_pf_remove(struct pci_dev *pdev)
 	enetc_free_msix(priv);
 
 	enetc_free_si_resources(priv);
-	enetc_teardown_cbdr(&si->cbd_ring);
 
 	free_netdev(si->ndev);
 
-	enetc_pci_remove(pdev);
+	enetc_psi_destroy(pdev);
+}
+
+static void enetc_fixup_clear_rss_rfs(struct pci_dev *pdev)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct enetc_si *si;
+
+	/* Only apply quirk for disabled functions. For the ones
+	 * that are enabled, enetc_pf_probe() will apply it.
+	 */
+	if (node && of_device_is_available(node))
+		return;
+
+	si = enetc_psi_create(pdev);
+	if (si)
+		enetc_psi_destroy(pdev);
 }
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_FREESCALE, ENETC_DEV_ID_PF,
+			enetc_fixup_clear_rss_rfs);
 
 static const struct pci_device_id enetc_pf_id_table[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_FREESCALE, ENETC_DEV_ID_PF) },
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 5bc81cc0a2de4d..46b252bbe50001 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -11,6 +11,7 @@
 #include <linux/pci.h>
 #include <linux/errno.h>
 #include <linux/ioport.h>
+#include <linux/of.h>
 #include <linux/proc_fs.h>
 #include <linux/slab.h>
 
@@ -332,6 +333,7 @@ void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
  */
 void pci_bus_add_device(struct pci_dev *dev)
 {
+	struct device_node *dn = dev->dev.of_node;
 	int retval;
 
 	/*
@@ -344,7 +346,7 @@ void pci_bus_add_device(struct pci_dev *dev)
 	pci_proc_attach_device(dev);
 	pci_bridge_d3_update(dev);
 
-	dev->match_driver = true;
+	dev->match_driver = !dn || of_device_is_available(dn);
 	retval = device_attach(&dev->dev);
 	if (retval < 0 && retval != -EPROBE_DEFER)
 		pci_warn(dev, "device attach failed (%d)\n", retval);
diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index e51219f9f523cd..3c158b17dcb537 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -34,11 +34,6 @@ int pci_set_of_node(struct pci_dev *dev)
 	if (!node)
 		return 0;
 
-	if (!of_device_is_available(node)) {
-		of_node_put(node);
-		return -ENODEV;
-	}
-
 	device_set_node(&dev->dev, of_fwnode_handle(node));
 	return 0;
 }