misc: rp1: drop overlay support

The RP1 driver can load an overlay at runtime to describe the inner
peripherals. This has led to a lot of confusion regarding the naming
of nodes, their topology and the reclaiming of related node resources.

Since the overlay is currently not fully functional, drop its support
in the driver in favor of the fully described static DT.

This also means that this driver does not depend on CONFIG_PCI_DYNAMIC_OF_NODES
and no longer requires PCI quirks to dynamically create the intermediate
PCI nodes.

Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/4b0aa7160877cf128b9bc713776bcac73c46eb24.1766077285.git.andrea.porta@suse.com
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

Author: Andrea della Porta

drivers/misc/rp1/Kconfig

@@ -5,8 +5,7 @@
 
 config MISC_RP1
 	tristate "RaspberryPi RP1 misc device"
-	depends on OF_IRQ && OF_OVERLAY && PCI_MSI && PCI_QUIRKS
-	select PCI_DYNAMIC_OF_NODES
+	depends on OF_IRQ && PCI_MSI
 	help
 	  Support the RP1 peripheral chip found on Raspberry Pi 5 board.
 
@@ -15,6 +14,3 @@ config MISC_RP1
 
 	  The driver is responsible for enabling the DT node once the PCIe
 	  endpoint has been configured, and handling interrupts.
-
-	  This driver uses an overlay to load other drivers to support for
-	  RP1 internal sub-devices.

drivers/misc/rp1/Makefile

@@ -1,3 +1,2 @@
 # SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_MISC_RP1)		+= rp1-pci.o
-rp1-pci-objs			:= rp1_pci.o rp1-pci.dtbo.o
+obj-$(CONFIG_MISC_RP1)		+= rp1_pci.o

drivers/misc/rp1/rp1-pci.dtso

@@ -34,16 +34,11 @@
 /* Interrupts */
 #define RP1_INT_END		61
 
-/* Embedded dtbo symbols created by cmd_wrap_S_dtb in scripts/Makefile.lib */
-extern char __dtbo_rp1_pci_begin[];
-extern char __dtbo_rp1_pci_end[];
-
 struct rp1_dev {
 	struct pci_dev *pdev;
 	struct irq_domain *domain;
 	struct irq_data *pcie_irqds[64];
 	void __iomem *bar1;
-	int ovcs_id;	/* overlay changeset id */
 	bool level_triggered_irq[RP1_INT_END];
 };
 
@@ -184,24 +179,13 @@ static void rp1_unregister_interrupts(struct pci_dev *pdev)
 
 static int rp1_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
-	u32 dtbo_size = __dtbo_rp1_pci_end - __dtbo_rp1_pci_begin;
-	void *dtbo_start = __dtbo_rp1_pci_begin;
 	struct device *dev = &pdev->dev;
 	struct device_node *rp1_node;
-	bool skip_ovl = true;
 	struct rp1_dev *rp1;
 	int err = 0;
 	int i;
 
-	/*
-	 * Either use rp1_nexus node if already present in DT, or
-	 * set a flag to load it from overlay at runtime
-	 */
-	rp1_node = of_find_node_by_name(NULL, "rp1_nexus");
-	if (!rp1_node) {
-		rp1_node = dev_of_node(dev);
-		skip_ovl = false;
-	}
+	rp1_node = dev_of_node(dev);
 
 	if (!rp1_node) {
 		dev_err(dev, "Missing of_node for device\n");
@@ -276,42 +260,29 @@ static int rp1_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 						 rp1_chained_handle_irq, rp1);
 	}
 
-	if (!skip_ovl) {
-		err = of_overlay_fdt_apply(dtbo_start, dtbo_size, &rp1->ovcs_id,
-					   rp1_node);
-		if (err)
-			goto err_unregister_interrupts;
-	}
-
 	err = of_platform_default_populate(rp1_node, NULL, dev);
 	if (err) {
 		dev_err_probe(&pdev->dev, err, "Error populating devicetree\n");
-		goto err_unload_overlay;
+		goto err_unregister_interrupts;
 	}
 
-	if (skip_ovl)
-		of_node_put(rp1_node);
+	of_node_put(rp1_node);
 
 	return 0;
 
-err_unload_overlay:
-	of_overlay_remove(&rp1->ovcs_id);
 err_unregister_interrupts:
 	rp1_unregister_interrupts(pdev);
 err_put_node:
-	if (skip_ovl)
-		of_node_put(rp1_node);
+	of_node_put(rp1_node);
 
 	return err;
 }
 
 static void rp1_remove(struct pci_dev *pdev)
 {
-	struct rp1_dev *rp1 = pci_get_drvdata(pdev);
 	struct device *dev = &pdev->dev;
 
 	of_platform_depopulate(dev);
-	of_overlay_remove(&rp1->ovcs_id);
 	rp1_unregister_interrupts(pdev);
 }
 

drivers/misc/rp1/rp1_pci.c

@@ -6308,7 +6308,6 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5020, of_pci_make_dev_node);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5021, of_pci_make_dev_node);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_REDHAT, 0x0005, of_pci_make_dev_node);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_EFAR, 0x9660, of_pci_make_dev_node);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_RPI, PCI_DEVICE_ID_RPI_RP1_C0, of_pci_make_dev_node);
 
 /*
  * Devices known to require a longer delay before first config space access