arch/powerpc/kernel/pci_64.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Port for PPC64 David Engebretsen, IBM Corp.
  * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
  *
  * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
  *   Rework, based on alpha PCI code.
  */

 #undef DEBUG

 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/string.h>
 #include <linux/init.h>
 #include <linux/export.h>
 #include <linux/mm.h>
 #include <linux/list.h>
 #include <linux/syscalls.h>
 #include <linux/irq.h>
 #include <linux/vmalloc.h>
 #include <linux/of.h>

 #include <asm/processor.h>
 #include <asm/io.h>
 #include <asm/pci-bridge.h>
 #include <asm/byteorder.h>
 #include <asm/machdep.h>
 #include <asm/ppc-pci.h>

 /* pci_io_base -- the base address from which io bars are offsets.
  * This is the lowest I/O base address (so bar values are always positive),
  * and it *must* be the start of ISA space if an ISA bus exists because
  * ISA drivers use hard coded offsets.  If no ISA bus exists nothing
  * is mapped on the first 64K of IO space
  */
 unsigned long pci_io_base;
 EXPORT_SYMBOL(pci_io_base);

 static int __init pcibios_init(void)
 {
 	struct pci_controller *hose, *tmp;

 	printk(KERN_INFO "PCI: Probing PCI hardware\n");

 	/* For now, override phys_mem_access_prot. If we need it,g
 	 * later, we may move that initialization to each ppc_md
 	 */
 	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;

 	/* On ppc64, we always enable PCI domains and we keep domain 0
 	 * backward compatible in /proc for video cards
 	 */
 	pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);

 	/* Scan all of the recorded PCI controllers.  */
 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
 		pcibios_scan_phb(hose);

 	/* Call common code to handle resource allocation */
 	pcibios_resource_survey();

 	/* Add devices. */
 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
 		pci_bus_add_devices(hose->bus);

 	/* Call machine dependent fixup */
 	if (ppc_md.pcibios_fixup)
 		ppc_md.pcibios_fixup();

 	printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");

 	return 0;
 }

 subsys_initcall(pcibios_init);

 int pcibios_unmap_io_space(struct pci_bus *bus)
 {
 	struct pci_controller *hose;

 	WARN_ON(bus == NULL);

 	/* If this is not a PHB, we only flush the hash table over
 	 * the area mapped by this bridge. We don't play with the PTE
 	 * mappings since we might have to deal with sub-page alignments
 	 * so flushing the hash table is the only sane way to make sure
 	 * that no hash entries are covering that removed bridge area
 	 * while still allowing other busses overlapping those pages
 	 *
 	 * Note: If we ever support P2P hotplug on Book3E, we'll have
 	 * to do an appropriate TLB flush here too
 	 */
 	if (bus->self) {
 #ifdef CONFIG_PPC_BOOK3S_64
 		struct resource *res = bus->resource[0];
 #endif

 		pr_debug("IO unmapping for PCI-PCI bridge %s\n",
 			 pci_name(bus->self));

 #ifdef CONFIG_PPC_BOOK3S_64
 		__flush_hash_table_range(res->start + _IO_BASE,
 					 res->end + _IO_BASE + 1);
 #endif
 		return 0;
 	}

 	/* Get the host bridge */
 	hose = pci_bus_to_host(bus);

 	pr_debug("IO unmapping for PHB %pOF\n", hose->dn);
 	pr_debug("  alloc=0x%p\n", hose->io_base_alloc);

 	iounmap(hose->io_base_alloc);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);

 void __iomem *ioremap_phb(phys_addr_t paddr, unsigned long size)
 {
 	struct vm_struct *area;
 	unsigned long addr;

 	WARN_ON_ONCE(paddr & ~PAGE_MASK);
 	WARN_ON_ONCE(size & ~PAGE_MASK);

 	/*
 	 * Let's allocate some IO space for that guy. We don't pass VM_IOREMAP
 	 * because we don't care about alignment tricks that the core does in
 	 * that case.  Maybe we should due to stupid card with incomplete
 	 * address decoding but I'd rather not deal with those outside of the
 	 * reserved 64K legacy region.
 	 */
 	area = __get_vm_area_caller(size, VM_IOREMAP, PHB_IO_BASE, PHB_IO_END,
 				    __builtin_return_address(0));
 	if (!area)
 		return NULL;

 	addr = (unsigned long)area->addr;
 	if (ioremap_page_range(addr, addr + size, paddr,
 			pgprot_noncached(PAGE_KERNEL))) {
 		vunmap_range(addr, addr + size);
 		return NULL;
 	}

 	return (void __iomem *)addr;
 }
 EXPORT_SYMBOL_GPL(ioremap_phb);

 static int pcibios_map_phb_io_space(struct pci_controller *hose)
 {
 	unsigned long phys_page;
 	unsigned long size_page;
 	unsigned long io_virt_offset;

 	phys_page = ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
 	size_page = ALIGN(hose->pci_io_size, PAGE_SIZE);

 	/* Make sure IO area address is clear */
 	hose->io_base_alloc = NULL;

 	/* If there's no IO to map on that bus, get away too */
 	if (hose->pci_io_size == 0 || hose->io_base_phys == 0)
 		return 0;

 	/* Let's allocate some IO space for that guy. We don't pass
 	 * VM_IOREMAP because we don't care about alignment tricks that
 	 * the core does in that case. Maybe we should due to stupid card
 	 * with incomplete address decoding but I'd rather not deal with
 	 * those outside of the reserved 64K legacy region.
 	 */
 	hose->io_base_alloc = ioremap_phb(phys_page, size_page);
 	if (!hose->io_base_alloc)
 		return -ENOMEM;
 	hose->io_base_virt = hose->io_base_alloc +
 				hose->io_base_phys - phys_page;

 	pr_debug("IO mapping for PHB %pOF\n", hose->dn);
 	pr_debug("  phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
 		 hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
 	pr_debug("  size=0x%016llx (alloc=0x%016lx)\n",
 		 hose->pci_io_size, size_page);

 	/* Fixup hose IO resource */
 	io_virt_offset = pcibios_io_space_offset(hose);
 	hose->io_resource.start += io_virt_offset;
 	hose->io_resource.end += io_virt_offset;

 	pr_debug("  hose->io_resource=%pR\n", &hose->io_resource);

 	return 0;
 }

 int pcibios_map_io_space(struct pci_bus *bus)
 {
 	WARN_ON(bus == NULL);

 	/* If this not a PHB, nothing to do, page tables still exist and
 	 * thus HPTEs will be faulted in when needed
 	 */
 	if (bus->self) {
 		pr_debug("IO mapping for PCI-PCI bridge %s\n",
 			 pci_name(bus->self));
 		pr_debug("  virt=0x%016llx...0x%016llx\n",
 			 bus->resource[0]->start + _IO_BASE,
 			 bus->resource[0]->end + _IO_BASE);
 		return 0;
 	}

 	return pcibios_map_phb_io_space(pci_bus_to_host(bus));
 }
 EXPORT_SYMBOL_GPL(pcibios_map_io_space);

 void pcibios_setup_phb_io_space(struct pci_controller *hose)
 {
 	pcibios_map_phb_io_space(hose);
 }

 #define IOBASE_BRIDGE_NUMBER	0
 #define IOBASE_MEMORY		1
 #define IOBASE_IO		2
 #define IOBASE_ISA_IO		3
 #define IOBASE_ISA_MEM		4

 SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, in_bus,
 			  unsigned long, in_devfn)
 {
 	struct pci_controller* hose;
 	struct pci_bus *tmp_bus, *bus = NULL;
 	struct device_node *hose_node;

 	/* Argh ! Please forgive me for that hack, but that's the
 	 * simplest way to get existing XFree to not lockup on some
 	 * G5 machines... So when something asks for bus 0 io base
 	 * (bus 0 is HT root), we return the AGP one instead.
 	 */
 	if (in_bus == 0 && of_machine_is_compatible("MacRISC4")) {
 		struct device_node *agp;

 		agp = of_find_compatible_node(NULL, NULL, "u3-agp");
 		if (agp)
 			in_bus = 0xf0;
 		of_node_put(agp);
 	}

 	/* That syscall isn't quite compatible with PCI domains, but it's
 	 * used on pre-domains setup. We return the first match
 	 */

 	list_for_each_entry(tmp_bus, &pci_root_buses, node) {
 		if (in_bus >= tmp_bus->number &&
 		    in_bus <= tmp_bus->busn_res.end) {
 			bus = tmp_bus;
 			break;
 		}
 	}
 	if (bus == NULL || bus->dev.of_node == NULL)
 		return -ENODEV;

 	hose_node = bus->dev.of_node;
 	hose = PCI_DN(hose_node)->phb;

 	switch (which) {
 	case IOBASE_BRIDGE_NUMBER:
 		return (long)hose->first_busno;
 	case IOBASE_MEMORY:
 		return (long)hose->mem_offset[0];
 	case IOBASE_IO:
 		return (long)hose->io_base_phys;
 	case IOBASE_ISA_IO:
 		return (long)isa_io_base;
 	case IOBASE_ISA_MEM:
 		return -EINVAL;
 	}

 	return -EOPNOTSUPP;
 }

 #ifdef CONFIG_NUMA
 int pcibus_to_node(struct pci_bus *bus)
 {
 	struct pci_controller *phb = pci_bus_to_host(bus);
 	return phb->node;
 }
 EXPORT_SYMBOL(pcibus_to_node);
 #endif

 #ifdef CONFIG_PPC_PMAC
 int pci_device_from_OF_node(struct device_node *np, u8 *bus, u8 *devfn)
 {
 	if (!PCI_DN(np))
 		return -ENODEV;
 	*bus = PCI_DN(np)->busno;
 	*devfn = PCI_DN(np)->devfn;
 	return 0;
 }
 #endif
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Port for PPC64 David Engebretsen, IBM Corp.
	* Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
	*
	* Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
	* Rework, based on alpha PCI code.
	*/

	#undef DEBUG

	#include <linux/kernel.h>
	#include <linux/pci.h>
	#include <linux/string.h>
	#include <linux/init.h>
	#include <linux/export.h>
	#include <linux/mm.h>
	#include <linux/list.h>
	#include <linux/syscalls.h>
	#include <linux/irq.h>
	#include <linux/vmalloc.h>
	#include <linux/of.h>

	#include <asm/processor.h>
	#include <asm/io.h>
	#include <asm/pci-bridge.h>
	#include <asm/byteorder.h>
	#include <asm/machdep.h>
	#include <asm/ppc-pci.h>

	/* pci_io_base -- the base address from which io bars are offsets.
	* This is the lowest I/O base address (so bar values are always positive),
	* and it must be the start of ISA space if an ISA bus exists because
	* ISA drivers use hard coded offsets. If no ISA bus exists nothing
	* is mapped on the first 64K of IO space
	*/
	unsigned long pci_io_base;
	EXPORT_SYMBOL(pci_io_base);

	static int __init pcibios_init(void)
	{
	struct pci_controller hose, tmp;

	printk(KERN_INFO "PCI: Probing PCI hardware\n");

	/* For now, override phys_mem_access_prot. If we need it,g
	* later, we may move that initialization to each ppc_md
	*/
	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;

	/* On ppc64, we always enable PCI domains and we keep domain 0
	* backward compatible in /proc for video cards
	*/
	pci_add_flags(PCI_ENABLE_PROC_DOMAINS \| PCI_COMPAT_DOMAIN_0);

	/* Scan all of the recorded PCI controllers. */
	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
	pcibios_scan_phb(hose);

	/* Call common code to handle resource allocation */
	pcibios_resource_survey();

	/* Add devices. */
	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
	pci_bus_add_devices(hose->bus);

	/* Call machine dependent fixup */
	if (ppc_md.pcibios_fixup)
	ppc_md.pcibios_fixup();

	printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");

	return 0;
	}

	subsys_initcall(pcibios_init);

	int pcibios_unmap_io_space(struct pci_bus *bus)
	{
	struct pci_controller *hose;

	WARN_ON(bus == NULL);

	/* If this is not a PHB, we only flush the hash table over
	* the area mapped by this bridge. We don't play with the PTE
	* mappings since we might have to deal with sub-page alignments
	* so flushing the hash table is the only sane way to make sure
	* that no hash entries are covering that removed bridge area
	* while still allowing other busses overlapping those pages
	*
	* Note: If we ever support P2P hotplug on Book3E, we'll have
	* to do an appropriate TLB flush here too
	*/
	if (bus->self) {
	#ifdef CONFIG_PPC_BOOK3S_64
	struct resource *res = bus->resource[0];
	#endif

	pr_debug("IO unmapping for PCI-PCI bridge %s\n",
	pci_name(bus->self));

	#ifdef CONFIG_PPC_BOOK3S_64
	__flush_hash_table_range(res->start + _IO_BASE,
	res->end + _IO_BASE + 1);
	#endif
	return 0;
	}

	/* Get the host bridge */
	hose = pci_bus_to_host(bus);

	pr_debug("IO unmapping for PHB %pOF\n", hose->dn);
	pr_debug(" alloc=0x%p\n", hose->io_base_alloc);

	iounmap(hose->io_base_alloc);
	return 0;
	}
	EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);

	void __iomem *ioremap_phb(phys_addr_t paddr, unsigned long size)
	{
	struct vm_struct *area;
	unsigned long addr;

	WARN_ON_ONCE(paddr & ~PAGE_MASK);
	WARN_ON_ONCE(size & ~PAGE_MASK);

	/*
	* Let's allocate some IO space for that guy. We don't pass VM_IOREMAP
	* because we don't care about alignment tricks that the core does in
	* that case. Maybe we should due to stupid card with incomplete
	* address decoding but I'd rather not deal with those outside of the
	* reserved 64K legacy region.
	*/
	area = __get_vm_area_caller(size, VM_IOREMAP, PHB_IO_BASE, PHB_IO_END,
	__builtin_return_address(0));
	if (!area)
	return NULL;

	addr = (unsigned long)area->addr;
	if (ioremap_page_range(addr, addr + size, paddr,
	pgprot_noncached(PAGE_KERNEL))) {
	vunmap_range(addr, addr + size);
	return NULL;
	}

	return (void __iomem *)addr;
	}
	EXPORT_SYMBOL_GPL(ioremap_phb);

	static int pcibios_map_phb_io_space(struct pci_controller *hose)
	{
	unsigned long phys_page;
	unsigned long size_page;
	unsigned long io_virt_offset;

	phys_page = ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
	size_page = ALIGN(hose->pci_io_size, PAGE_SIZE);

	/* Make sure IO area address is clear */
	hose->io_base_alloc = NULL;

	/* If there's no IO to map on that bus, get away too */
	if (hose->pci_io_size == 0 \|\| hose->io_base_phys == 0)
	return 0;

	/* Let's allocate some IO space for that guy. We don't pass
	* VM_IOREMAP because we don't care about alignment tricks that
	* the core does in that case. Maybe we should due to stupid card
	* with incomplete address decoding but I'd rather not deal with
	* those outside of the reserved 64K legacy region.
	*/
	hose->io_base_alloc = ioremap_phb(phys_page, size_page);
	if (!hose->io_base_alloc)
	return -ENOMEM;
	hose->io_base_virt = hose->io_base_alloc +
	hose->io_base_phys - phys_page;

	pr_debug("IO mapping for PHB %pOF\n", hose->dn);
	pr_debug(" phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
	hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
	pr_debug(" size=0x%016llx (alloc=0x%016lx)\n",
	hose->pci_io_size, size_page);

	/* Fixup hose IO resource */
	io_virt_offset = pcibios_io_space_offset(hose);
	hose->io_resource.start += io_virt_offset;
	hose->io_resource.end += io_virt_offset;

	pr_debug(" hose->io_resource=%pR\n", &hose->io_resource);

	return 0;
	}

	int pcibios_map_io_space(struct pci_bus *bus)
	{
	WARN_ON(bus == NULL);

	/* If this not a PHB, nothing to do, page tables still exist and
	* thus HPTEs will be faulted in when needed
	*/
	if (bus->self) {
	pr_debug("IO mapping for PCI-PCI bridge %s\n",
	pci_name(bus->self));
	pr_debug(" virt=0x%016llx...0x%016llx\n",
	bus->resource[0]->start + _IO_BASE,
	bus->resource[0]->end + _IO_BASE);
	return 0;
	}

	return pcibios_map_phb_io_space(pci_bus_to_host(bus));
	}
	EXPORT_SYMBOL_GPL(pcibios_map_io_space);

	void pcibios_setup_phb_io_space(struct pci_controller *hose)
	{
	pcibios_map_phb_io_space(hose);
	}

	#define IOBASE_BRIDGE_NUMBER 0
	#define IOBASE_MEMORY 1
	#define IOBASE_IO 2
	#define IOBASE_ISA_IO 3
	#define IOBASE_ISA_MEM 4

	SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, in_bus,
	unsigned long, in_devfn)
	{
	struct pci_controller* hose;
	struct pci_bus tmp_bus, bus = NULL;
	struct device_node *hose_node;

	/* Argh ! Please forgive me for that hack, but that's the
	* simplest way to get existing XFree to not lockup on some
	* G5 machines... So when something asks for bus 0 io base
	* (bus 0 is HT root), we return the AGP one instead.
	*/
	if (in_bus == 0 && of_machine_is_compatible("MacRISC4")) {
	struct device_node *agp;

	agp = of_find_compatible_node(NULL, NULL, "u3-agp");
	if (agp)
	in_bus = 0xf0;
	of_node_put(agp);
	}

	/* That syscall isn't quite compatible with PCI domains, but it's
	* used on pre-domains setup. We return the first match
	*/

	list_for_each_entry(tmp_bus, &pci_root_buses, node) {
	if (in_bus >= tmp_bus->number &&
	in_bus <= tmp_bus->busn_res.end) {
	bus = tmp_bus;
	break;
	}
	}
	if (bus == NULL \|\| bus->dev.of_node == NULL)
	return -ENODEV;

	hose_node = bus->dev.of_node;
	hose = PCI_DN(hose_node)->phb;

	switch (which) {
	case IOBASE_BRIDGE_NUMBER:
	return (long)hose->first_busno;
	case IOBASE_MEMORY:
	return (long)hose->mem_offset[0];
	case IOBASE_IO:
	return (long)hose->io_base_phys;
	case IOBASE_ISA_IO:
	return (long)isa_io_base;
	case IOBASE_ISA_MEM:
	return -EINVAL;
	}

	return -EOPNOTSUPP;
	}

	#ifdef CONFIG_NUMA
	int pcibus_to_node(struct pci_bus *bus)
	{
	struct pci_controller *phb = pci_bus_to_host(bus);
	return phb->node;
	}
	EXPORT_SYMBOL(pcibus_to_node);
	#endif

	#ifdef CONFIG_PPC_PMAC
	int pci_device_from_OF_node(struct device_node np, u8 bus, u8 *devfn)
	{
	if (!PCI_DN(np))
	return -ENODEV;
	*bus = PCI_DN(np)->busno;
	*devfn = PCI_DN(np)->devfn;
	return 0;
	}
	#endif