Merge branch 'acpi-riscv'

Merge ACPI and irqchip updates related to external interrupt controller
support on RISC-V:

 - Add ACPI device enumeration support for interrupt controller probing
   including taking dependencies into account (Sunil V L).

 - Implement ACPI-based interrupt controller probing on RISC-V (Sunil V L).

 - Add ACPI support for AIA in riscv-intc and add ACPI support to
   riscv-imsic, riscv-aplic, and sifive-plic (Sunil V L).

* acpi-riscv:
  irqchip/sifive-plic: Add ACPI support
  irqchip/riscv-aplic: Add ACPI support
  irqchip/riscv-imsic: Add ACPI support
  irqchip/riscv-imsic-state: Create separate function for DT
  irqchip/riscv-intc: Add ACPI support for AIA
  ACPI: RISC-V: Implement function to add implicit dependencies
  ACPI: RISC-V: Initialize GSI mapping structures
  ACPI: RISC-V: Implement function to reorder irqchip probe entries
  ACPI: RISC-V: Implement PCI related functionality
  ACPI: pci_link: Clear the dependencies after probe
  ACPI: bus: Add RINTC IRQ model for RISC-V
  ACPI: scan: Define weak function to populate dependencies
  ACPI: scan: Add RISC-V interrupt controllers to honor list
  ACPI: scan: Refactor dependency creation
  ACPI: bus: Add acpi_riscv_init() function
  ACPI: scan: Add a weak arch_sort_irqchip_probe() to order the IRQCHIP probe
  arm64: PCI: Migrate ACPI related functions to pci-acpi.c

Author: rafaeljw

arch/arm64/kernel/pci.c

@@ -6,28 +6,7 @@
  * Copyright (C) 2014 ARM Ltd.
  */
 
-#include <linux/acpi.h>
-#include <linux/init.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
 #include <linux/pci.h>
-#include <linux/pci-acpi.h>
-#include <linux/pci-ecam.h>
-#include <linux/slab.h>
-
-#ifdef CONFIG_ACPI
-/*
- * Try to assign the IRQ number when probing a new device
- */
-int pcibios_alloc_irq(struct pci_dev *dev)
-{
-	if (!acpi_disabled)
-		acpi_pci_irq_enable(dev);
-
-	return 0;
-}
-#endif
 
 /*
  * raw_pci_read/write - Platform-specific PCI config space access.
@@ -61,173 +40,3 @@ int pcibus_to_node(struct pci_bus *bus)
 EXPORT_SYMBOL(pcibus_to_node);
 
 #endif
-
-#ifdef CONFIG_ACPI
-
-struct acpi_pci_generic_root_info {
-	struct acpi_pci_root_info	common;
-	struct pci_config_window	*cfg;	/* config space mapping */
-};
-
-int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
-{
-	struct pci_config_window *cfg = bus->sysdata;
-	struct acpi_device *adev = to_acpi_device(cfg->parent);
-	struct acpi_pci_root *root = acpi_driver_data(adev);
-
-	return root->segment;
-}
-
-int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
-{
-	struct pci_config_window *cfg;
-	struct acpi_device *adev;
-	struct device *bus_dev;
-
-	if (acpi_disabled)
-		return 0;
-
-	cfg = bridge->bus->sysdata;
-
-	/*
-	 * On Hyper-V there is no corresponding ACPI device for a root bridge,
-	 * therefore ->parent is set as NULL by the driver. And set 'adev' as
-	 * NULL in this case because there is no proper ACPI device.
-	 */
-	if (!cfg->parent)
-		adev = NULL;
-	else
-		adev = to_acpi_device(cfg->parent);
-
-	bus_dev = &bridge->bus->dev;
-
-	ACPI_COMPANION_SET(&bridge->dev, adev);
-	set_dev_node(bus_dev, acpi_get_node(acpi_device_handle(adev)));
-
-	return 0;
-}
-
-static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci)
-{
-	struct resource_entry *entry, *tmp;
-	int status;
-
-	status = acpi_pci_probe_root_resources(ci);
-	resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
-		if (!(entry->res->flags & IORESOURCE_WINDOW))
-			resource_list_destroy_entry(entry);
-	}
-	return status;
-}
-
-/*
- * Lookup the bus range for the domain in MCFG, and set up config space
- * mapping.
- */
-static struct pci_config_window *
-pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root)
-{
-	struct device *dev = &root->device->dev;
-	struct resource *bus_res = &root->secondary;
-	u16 seg = root->segment;
-	const struct pci_ecam_ops *ecam_ops;
-	struct resource cfgres;
-	struct acpi_device *adev;
-	struct pci_config_window *cfg;
-	int ret;
-
-	ret = pci_mcfg_lookup(root, &cfgres, &ecam_ops);
-	if (ret) {
-		dev_err(dev, "%04x:%pR ECAM region not found\n", seg, bus_res);
-		return NULL;
-	}
-
-	adev = acpi_resource_consumer(&cfgres);
-	if (adev)
-		dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres,
-			 dev_name(&adev->dev));
-	else
-		dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n",
-			 &cfgres);
-
-	cfg = pci_ecam_create(dev, &cfgres, bus_res, ecam_ops);
-	if (IS_ERR(cfg)) {
-		dev_err(dev, "%04x:%pR error %ld mapping ECAM\n", seg, bus_res,
-			PTR_ERR(cfg));
-		return NULL;
-	}
-
-	return cfg;
-}
-
-/* release_info: free resources allocated by init_info */
-static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci)
-{
-	struct acpi_pci_generic_root_info *ri;
-
-	ri = container_of(ci, struct acpi_pci_generic_root_info, common);
-	pci_ecam_free(ri->cfg);
-	kfree(ci->ops);
-	kfree(ri);
-}
-
-/* Interface called from ACPI code to setup PCI host controller */
-struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
-{
-	struct acpi_pci_generic_root_info *ri;
-	struct pci_bus *bus, *child;
-	struct acpi_pci_root_ops *root_ops;
-	struct pci_host_bridge *host;
-
-	ri = kzalloc(sizeof(*ri), GFP_KERNEL);
-	if (!ri)
-		return NULL;
-
-	root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL);
-	if (!root_ops) {
-		kfree(ri);
-		return NULL;
-	}
-
-	ri->cfg = pci_acpi_setup_ecam_mapping(root);
-	if (!ri->cfg) {
-		kfree(ri);
-		kfree(root_ops);
-		return NULL;
-	}
-
-	root_ops->release_info = pci_acpi_generic_release_info;
-	root_ops->prepare_resources = pci_acpi_root_prepare_resources;
-	root_ops->pci_ops = (struct pci_ops *)&ri->cfg->ops->pci_ops;
-	bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg);
-	if (!bus)
-		return NULL;
-
-	/* If we must preserve the resource configuration, claim now */
-	host = pci_find_host_bridge(bus);
-	if (host->preserve_config)
-		pci_bus_claim_resources(bus);
-
-	/*
-	 * Assign whatever was left unassigned. If we didn't claim above,
-	 * this will reassign everything.
-	 */
-	pci_assign_unassigned_root_bus_resources(bus);
-
-	list_for_each_entry(child, &bus->children, node)
-		pcie_bus_configure_settings(child);
-
-	return bus;
-}
-
-void pcibios_add_bus(struct pci_bus *bus)
-{
-	acpi_pci_add_bus(bus);
-}
-
-void pcibios_remove_bus(struct pci_bus *bus)
-{
-	acpi_pci_remove_bus(bus);
-}
-
-#endif

arch/riscv/Kconfig

@@ -13,6 +13,7 @@ config 32BIT
 config RISCV
 	def_bool y
 	select ACPI_GENERIC_GSI if ACPI
+	select ACPI_MCFG if (ACPI && PCI)
 	select ACPI_PPTT if ACPI
 	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
 	select ACPI_SPCR_TABLE if ACPI
@@ -188,6 +189,7 @@ config RISCV
 	select OF_EARLY_FLATTREE
 	select OF_IRQ
 	select PCI_DOMAINS_GENERIC if PCI
+	select PCI_ECAM if (ACPI && PCI)
 	select PCI_MSI if PCI
 	select RISCV_ALTERNATIVE if !XIP_KERNEL
 	select RISCV_APLIC

arch/riscv/include/asm/irq.h

@@ -12,8 +12,63 @@
 
 #include <asm-generic/irq.h>
 
+#define INVALID_CONTEXT UINT_MAX
+
 void riscv_set_intc_hwnode_fn(struct fwnode_handle *(*fn)(void));
 
 struct fwnode_handle *riscv_get_intc_hwnode(void);
 
+#ifdef CONFIG_ACPI
+
+enum riscv_irqchip_type {
+	ACPI_RISCV_IRQCHIP_INTC		= 0x00,
+	ACPI_RISCV_IRQCHIP_IMSIC	= 0x01,
+	ACPI_RISCV_IRQCHIP_PLIC		= 0x02,
+	ACPI_RISCV_IRQCHIP_APLIC	= 0x03,
+};
+
+int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
+			    u32 *id, u32 *nr_irqs, u32 *nr_idcs);
+struct fwnode_handle *riscv_acpi_get_gsi_domain_id(u32 gsi);
+unsigned long acpi_rintc_index_to_hartid(u32 index);
+unsigned long acpi_rintc_ext_parent_to_hartid(unsigned int plic_id, unsigned int ctxt_idx);
+unsigned int acpi_rintc_get_plic_nr_contexts(unsigned int plic_id);
+unsigned int acpi_rintc_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx);
+int __init acpi_rintc_get_imsic_mmio_info(u32 index, struct resource *res);
+
+#else
+static inline int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
+					  u32 *id, u32 *nr_irqs, u32 *nr_idcs)
+{
+	return 0;
+}
+
+static inline unsigned long acpi_rintc_index_to_hartid(u32 index)
+{
+	return INVALID_HARTID;
+}
+
+static inline unsigned long acpi_rintc_ext_parent_to_hartid(unsigned int plic_id,
+							    unsigned int ctxt_idx)
+{
+	return INVALID_HARTID;
+}
+
+static inline unsigned int acpi_rintc_get_plic_nr_contexts(unsigned int plic_id)
+{
+	return INVALID_CONTEXT;
+}
+
+static inline unsigned int acpi_rintc_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx)
+{
+	return INVALID_CONTEXT;
+}
+
+static inline int __init acpi_rintc_get_imsic_mmio_info(u32 index, struct resource *res)
+{
+	return 0;
+}
+
+#endif /* CONFIG_ACPI */
+
 #endif /* _ASM_RISCV_IRQ_H */

arch/riscv/kernel/acpi.c

@@ -311,29 +311,26 @@ void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size)
 #ifdef CONFIG_PCI
 
 /*
- * These interfaces are defined just to enable building ACPI core.
- * TODO: Update it with actual implementation when external interrupt
- * controller support is added in RISC-V ACPI.
+ * raw_pci_read/write - Platform-specific PCI config space access.
  */
-int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
-		 int reg, int len, u32 *val)
+int raw_pci_read(unsigned int domain, unsigned int bus,
+		 unsigned int devfn, int reg, int len, u32 *val)
 {
-	return PCIBIOS_DEVICE_NOT_FOUND;
-}
+	struct pci_bus *b = pci_find_bus(domain, bus);
 
-int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
-		  int reg, int len, u32 val)
-{
-	return PCIBIOS_DEVICE_NOT_FOUND;
+	if (!b)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	return b->ops->read(b, devfn, reg, len, val);
 }
 
-int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
+int raw_pci_write(unsigned int domain, unsigned int bus,
+		  unsigned int devfn, int reg, int len, u32 val)
 {
-	return -1;
-}
+	struct pci_bus *b = pci_find_bus(domain, bus);
 
-struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
-{
-	return NULL;
+	if (!b)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	return b->ops->write(b, devfn, reg, len, val);
 }
+
 #endif	/* CONFIG_PCI */

drivers/acpi/bus.c

@@ -1203,6 +1203,9 @@ static int __init acpi_bus_init_irq(void)
 	case ACPI_IRQ_MODEL_LPIC:
 		message = "LPIC";
 		break;
+	case ACPI_IRQ_MODEL_RINTC:
+		message = "RINTC";
+		break;
 	default:
 		pr_info("Unknown interrupt routing model\n");
 		return -ENODEV;
@@ -1459,6 +1462,7 @@ static int __init acpi_init(void)
 	acpi_hest_init();
 	acpi_ghes_init();
 	acpi_arm_init();
+	acpi_riscv_init();
 	acpi_scan_init();
 	acpi_ec_init();
 	acpi_debugfs_init();

drivers/acpi/pci_link.c

@@ -748,6 +748,8 @@ static int acpi_pci_link_add(struct acpi_device *device,
 	if (result)
 		kfree(link);
 
+	acpi_dev_clear_dependencies(device);
+
 	return result < 0 ? result : 1;
 }
 

drivers/acpi/riscv/Makefile

@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
-obj-y					+= rhct.o
+obj-y					+= rhct.o init.o irq.o
 obj-$(CONFIG_ACPI_PROCESSOR_IDLE)	+= cpuidle.o
 obj-$(CONFIG_ACPI_CPPC_LIB)		+= cppc.o

drivers/acpi/riscv/init.c

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023-2024, Ventana Micro Systems Inc
+ *	Author: Sunil V L <[email protected]>
+ */
+
+#include <linux/acpi.h>
+#include "init.h"
+
+void __init acpi_riscv_init(void)
+{
+	riscv_acpi_init_gsi_mapping();
+}

drivers/acpi/riscv/init.h

@@ -0,0 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#include <linux/init.h>
+
+void __init riscv_acpi_init_gsi_mapping(void);