xref: /openbmc/linux/arch/powerpc/kernel/pci_64.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Port for PPC64 David Engebretsen, IBM Corp.
4  * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
5  *
6  * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
7  *   Rework, based on alpha PCI code.
8  */
9 
10 #undef DEBUG
11 
12 #include <linux/kernel.h>
13 #include <linux/pci.h>
14 #include <linux/string.h>
15 #include <linux/init.h>
16 #include <linux/export.h>
17 #include <linux/mm.h>
18 #include <linux/list.h>
19 #include <linux/syscalls.h>
20 #include <linux/irq.h>
21 #include <linux/vmalloc.h>
22 
23 #include <asm/processor.h>
24 #include <asm/io.h>
25 #include <asm/prom.h>
26 #include <asm/pci-bridge.h>
27 #include <asm/byteorder.h>
28 #include <asm/machdep.h>
29 #include <asm/ppc-pci.h>
30 
31 /* pci_io_base -- the base address from which io bars are offsets.
32  * This is the lowest I/O base address (so bar values are always positive),
33  * and it *must* be the start of ISA space if an ISA bus exists because
34  * ISA drivers use hard coded offsets.  If no ISA bus exists nothing
35  * is mapped on the first 64K of IO space
36  */
37 unsigned long pci_io_base;
38 EXPORT_SYMBOL(pci_io_base);
39 
40 static int __init pcibios_init(void)
41 {
42 	struct pci_controller *hose, *tmp;
43 
44 	printk(KERN_INFO "PCI: Probing PCI hardware\n");
45 
46 	/* For now, override phys_mem_access_prot. If we need it,g
47 	 * later, we may move that initialization to each ppc_md
48 	 */
49 	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;
50 
51 	/* On ppc64, we always enable PCI domains and we keep domain 0
52 	 * backward compatible in /proc for video cards
53 	 */
54 	pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);
55 
56 	/* Scan all of the recorded PCI controllers.  */
57 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
58 		pcibios_scan_phb(hose);
59 
60 	/* Call common code to handle resource allocation */
61 	pcibios_resource_survey();
62 
63 	/* Add devices. */
64 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
65 		pci_bus_add_devices(hose->bus);
66 
67 	/* Call machine dependent fixup */
68 	if (ppc_md.pcibios_fixup)
69 		ppc_md.pcibios_fixup();
70 
71 	printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");
72 
73 	return 0;
74 }
75 
76 subsys_initcall(pcibios_init);
77 
78 int pcibios_unmap_io_space(struct pci_bus *bus)
79 {
80 	struct pci_controller *hose;
81 
82 	WARN_ON(bus == NULL);
83 
84 	/* If this is not a PHB, we only flush the hash table over
85 	 * the area mapped by this bridge. We don't play with the PTE
86 	 * mappings since we might have to deal with sub-page alignments
87 	 * so flushing the hash table is the only sane way to make sure
88 	 * that no hash entries are covering that removed bridge area
89 	 * while still allowing other busses overlapping those pages
90 	 *
91 	 * Note: If we ever support P2P hotplug on Book3E, we'll have
92 	 * to do an appropriate TLB flush here too
93 	 */
94 	if (bus->self) {
95 #ifdef CONFIG_PPC_BOOK3S_64
96 		struct resource *res = bus->resource[0];
97 #endif
98 
99 		pr_debug("IO unmapping for PCI-PCI bridge %s\n",
100 			 pci_name(bus->self));
101 
102 #ifdef CONFIG_PPC_BOOK3S_64
103 		__flush_hash_table_range(res->start + _IO_BASE,
104 					 res->end + _IO_BASE + 1);
105 #endif
106 		return 0;
107 	}
108 
109 	/* Get the host bridge */
110 	hose = pci_bus_to_host(bus);
111 
112 	pr_debug("IO unmapping for PHB %pOF\n", hose->dn);
113 	pr_debug("  alloc=0x%p\n", hose->io_base_alloc);
114 
115 	iounmap(hose->io_base_alloc);
116 	return 0;
117 }
118 EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);
119 
120 void __iomem *ioremap_phb(phys_addr_t paddr, unsigned long size)
121 {
122 	struct vm_struct *area;
123 	unsigned long addr;
124 
125 	WARN_ON_ONCE(paddr & ~PAGE_MASK);
126 	WARN_ON_ONCE(size & ~PAGE_MASK);
127 
128 	/*
129 	 * Let's allocate some IO space for that guy. We don't pass VM_IOREMAP
130 	 * because we don't care about alignment tricks that the core does in
131 	 * that case.  Maybe we should due to stupid card with incomplete
132 	 * address decoding but I'd rather not deal with those outside of the
133 	 * reserved 64K legacy region.
134 	 */
135 	area = __get_vm_area_caller(size, 0, PHB_IO_BASE, PHB_IO_END,
136 				    __builtin_return_address(0));
137 	if (!area)
138 		return NULL;
139 
140 	addr = (unsigned long)area->addr;
141 	if (ioremap_page_range(addr, addr + size, paddr,
142 			pgprot_noncached(PAGE_KERNEL))) {
143 		vunmap_range(addr, addr + size);
144 		return NULL;
145 	}
146 
147 	return (void __iomem *)addr;
148 }
149 EXPORT_SYMBOL_GPL(ioremap_phb);
150 
151 static int pcibios_map_phb_io_space(struct pci_controller *hose)
152 {
153 	unsigned long phys_page;
154 	unsigned long size_page;
155 	unsigned long io_virt_offset;
156 
157 	phys_page = ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
158 	size_page = ALIGN(hose->pci_io_size, PAGE_SIZE);
159 
160 	/* Make sure IO area address is clear */
161 	hose->io_base_alloc = NULL;
162 
163 	/* If there's no IO to map on that bus, get away too */
164 	if (hose->pci_io_size == 0 || hose->io_base_phys == 0)
165 		return 0;
166 
167 	/* Let's allocate some IO space for that guy. We don't pass
168 	 * VM_IOREMAP because we don't care about alignment tricks that
169 	 * the core does in that case. Maybe we should due to stupid card
170 	 * with incomplete address decoding but I'd rather not deal with
171 	 * those outside of the reserved 64K legacy region.
172 	 */
173 	hose->io_base_alloc = ioremap_phb(phys_page, size_page);
174 	if (!hose->io_base_alloc)
175 		return -ENOMEM;
176 	hose->io_base_virt = hose->io_base_alloc +
177 				hose->io_base_phys - phys_page;
178 
179 	pr_debug("IO mapping for PHB %pOF\n", hose->dn);
180 	pr_debug("  phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
181 		 hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
182 	pr_debug("  size=0x%016llx (alloc=0x%016lx)\n",
183 		 hose->pci_io_size, size_page);
184 
185 	/* Fixup hose IO resource */
186 	io_virt_offset = pcibios_io_space_offset(hose);
187 	hose->io_resource.start += io_virt_offset;
188 	hose->io_resource.end += io_virt_offset;
189 
190 	pr_debug("  hose->io_resource=%pR\n", &hose->io_resource);
191 
192 	return 0;
193 }
194 
195 int pcibios_map_io_space(struct pci_bus *bus)
196 {
197 	WARN_ON(bus == NULL);
198 
199 	/* If this not a PHB, nothing to do, page tables still exist and
200 	 * thus HPTEs will be faulted in when needed
201 	 */
202 	if (bus->self) {
203 		pr_debug("IO mapping for PCI-PCI bridge %s\n",
204 			 pci_name(bus->self));
205 		pr_debug("  virt=0x%016llx...0x%016llx\n",
206 			 bus->resource[0]->start + _IO_BASE,
207 			 bus->resource[0]->end + _IO_BASE);
208 		return 0;
209 	}
210 
211 	return pcibios_map_phb_io_space(pci_bus_to_host(bus));
212 }
213 EXPORT_SYMBOL_GPL(pcibios_map_io_space);
214 
215 void pcibios_setup_phb_io_space(struct pci_controller *hose)
216 {
217 	pcibios_map_phb_io_space(hose);
218 }
219 
220 #define IOBASE_BRIDGE_NUMBER	0
221 #define IOBASE_MEMORY		1
222 #define IOBASE_IO		2
223 #define IOBASE_ISA_IO		3
224 #define IOBASE_ISA_MEM		4
225 
226 SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, in_bus,
227 			  unsigned long, in_devfn)
228 {
229 	struct pci_controller* hose;
230 	struct pci_bus *tmp_bus, *bus = NULL;
231 	struct device_node *hose_node;
232 
233 	/* Argh ! Please forgive me for that hack, but that's the
234 	 * simplest way to get existing XFree to not lockup on some
235 	 * G5 machines... So when something asks for bus 0 io base
236 	 * (bus 0 is HT root), we return the AGP one instead.
237 	 */
238 	if (in_bus == 0 && of_machine_is_compatible("MacRISC4")) {
239 		struct device_node *agp;
240 
241 		agp = of_find_compatible_node(NULL, NULL, "u3-agp");
242 		if (agp)
243 			in_bus = 0xf0;
244 		of_node_put(agp);
245 	}
246 
247 	/* That syscall isn't quite compatible with PCI domains, but it's
248 	 * used on pre-domains setup. We return the first match
249 	 */
250 
251 	list_for_each_entry(tmp_bus, &pci_root_buses, node) {
252 		if (in_bus >= tmp_bus->number &&
253 		    in_bus <= tmp_bus->busn_res.end) {
254 			bus = tmp_bus;
255 			break;
256 		}
257 	}
258 	if (bus == NULL || bus->dev.of_node == NULL)
259 		return -ENODEV;
260 
261 	hose_node = bus->dev.of_node;
262 	hose = PCI_DN(hose_node)->phb;
263 
264 	switch (which) {
265 	case IOBASE_BRIDGE_NUMBER:
266 		return (long)hose->first_busno;
267 	case IOBASE_MEMORY:
268 		return (long)hose->mem_offset[0];
269 	case IOBASE_IO:
270 		return (long)hose->io_base_phys;
271 	case IOBASE_ISA_IO:
272 		return (long)isa_io_base;
273 	case IOBASE_ISA_MEM:
274 		return -EINVAL;
275 	}
276 
277 	return -EOPNOTSUPP;
278 }
279 
280 #ifdef CONFIG_NUMA
281 int pcibus_to_node(struct pci_bus *bus)
282 {
283 	struct pci_controller *phb = pci_bus_to_host(bus);
284 	return phb->node;
285 }
286 EXPORT_SYMBOL(pcibus_to_node);
287 #endif
288