xref: /linux/arch/powerpc/kernel/pci_64.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Port for PPC64 David Engebretsen, IBM Corp.
3  * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
4  *
5  * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
6  *   Rework, based on alpha PCI code.
7  *
8  *      This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  */
13 
14 #undef DEBUG
15 
16 #include <linux/kernel.h>
17 #include <linux/pci.h>
18 #include <linux/string.h>
19 #include <linux/init.h>
20 #include <linux/bootmem.h>
21 #include <linux/export.h>
22 #include <linux/mm.h>
23 #include <linux/list.h>
24 #include <linux/syscalls.h>
25 #include <linux/irq.h>
26 #include <linux/vmalloc.h>
27 
28 #include <asm/processor.h>
29 #include <asm/io.h>
30 #include <asm/prom.h>
31 #include <asm/pci-bridge.h>
32 #include <asm/byteorder.h>
33 #include <asm/machdep.h>
34 #include <asm/ppc-pci.h>
35 
36 unsigned long pci_probe_only = 1;
37 
38 /* pci_io_base -- the base address from which io bars are offsets.
39  * This is the lowest I/O base address (so bar values are always positive),
40  * and it *must* be the start of ISA space if an ISA bus exists because
41  * ISA drivers use hard coded offsets.  If no ISA bus exists nothing
42  * is mapped on the first 64K of IO space
43  */
44 unsigned long pci_io_base = ISA_IO_BASE;
45 EXPORT_SYMBOL(pci_io_base);
46 
47 static int __init pcibios_init(void)
48 {
49 	struct pci_controller *hose, *tmp;
50 
51 	printk(KERN_INFO "PCI: Probing PCI hardware\n");
52 
53 	/* For now, override phys_mem_access_prot. If we need it,g
54 	 * later, we may move that initialization to each ppc_md
55 	 */
56 	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;
57 
58 	if (pci_probe_only)
59 		pci_add_flags(PCI_PROBE_ONLY);
60 
61 	/* On ppc64, we always enable PCI domains and we keep domain 0
62 	 * backward compatible in /proc for video cards
63 	 */
64 	pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);
65 
66 	/* Scan all of the recorded PCI controllers.  */
67 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
68 		pcibios_scan_phb(hose);
69 		pci_bus_add_devices(hose->bus);
70 	}
71 
72 	/* Call common code to handle resource allocation */
73 	pcibios_resource_survey();
74 
75 	printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");
76 
77 	return 0;
78 }
79 
80 subsys_initcall(pcibios_init);
81 
82 #ifdef CONFIG_HOTPLUG
83 
84 int pcibios_unmap_io_space(struct pci_bus *bus)
85 {
86 	struct pci_controller *hose;
87 
88 	WARN_ON(bus == NULL);
89 
90 	/* If this is not a PHB, we only flush the hash table over
91 	 * the area mapped by this bridge. We don't play with the PTE
92 	 * mappings since we might have to deal with sub-page alignemnts
93 	 * so flushing the hash table is the only sane way to make sure
94 	 * that no hash entries are covering that removed bridge area
95 	 * while still allowing other busses overlapping those pages
96 	 *
97 	 * Note: If we ever support P2P hotplug on Book3E, we'll have
98 	 * to do an appropriate TLB flush here too
99 	 */
100 	if (bus->self) {
101 #ifdef CONFIG_PPC_STD_MMU_64
102 		struct resource *res = bus->resource[0];
103 #endif
104 
105 		pr_debug("IO unmapping for PCI-PCI bridge %s\n",
106 			 pci_name(bus->self));
107 
108 #ifdef CONFIG_PPC_STD_MMU_64
109 		__flush_hash_table_range(&init_mm, res->start + _IO_BASE,
110 					 res->end + _IO_BASE + 1);
111 #endif
112 		return 0;
113 	}
114 
115 	/* Get the host bridge */
116 	hose = pci_bus_to_host(bus);
117 
118 	/* Check if we have IOs allocated */
119 	if (hose->io_base_alloc == 0)
120 		return 0;
121 
122 	pr_debug("IO unmapping for PHB %s\n", hose->dn->full_name);
123 	pr_debug("  alloc=0x%p\n", hose->io_base_alloc);
124 
125 	/* This is a PHB, we fully unmap the IO area */
126 	vunmap(hose->io_base_alloc);
127 
128 	return 0;
129 }
130 EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);
131 
132 #endif /* CONFIG_HOTPLUG */
133 
134 static int __devinit pcibios_map_phb_io_space(struct pci_controller *hose)
135 {
136 	struct vm_struct *area;
137 	unsigned long phys_page;
138 	unsigned long size_page;
139 	unsigned long io_virt_offset;
140 
141 	phys_page = _ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
142 	size_page = _ALIGN_UP(hose->pci_io_size, PAGE_SIZE);
143 
144 	/* Make sure IO area address is clear */
145 	hose->io_base_alloc = NULL;
146 
147 	/* If there's no IO to map on that bus, get away too */
148 	if (hose->pci_io_size == 0 || hose->io_base_phys == 0)
149 		return 0;
150 
151 	/* Let's allocate some IO space for that guy. We don't pass
152 	 * VM_IOREMAP because we don't care about alignment tricks that
153 	 * the core does in that case. Maybe we should due to stupid card
154 	 * with incomplete address decoding but I'd rather not deal with
155 	 * those outside of the reserved 64K legacy region.
156 	 */
157 	area = __get_vm_area(size_page, 0, PHB_IO_BASE, PHB_IO_END);
158 	if (area == NULL)
159 		return -ENOMEM;
160 	hose->io_base_alloc = area->addr;
161 	hose->io_base_virt = (void __iomem *)(area->addr +
162 					      hose->io_base_phys - phys_page);
163 
164 	pr_debug("IO mapping for PHB %s\n", hose->dn->full_name);
165 	pr_debug("  phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
166 		 hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
167 	pr_debug("  size=0x%016llx (alloc=0x%016lx)\n",
168 		 hose->pci_io_size, size_page);
169 
170 	/* Establish the mapping */
171 	if (__ioremap_at(phys_page, area->addr, size_page,
172 			 _PAGE_NO_CACHE | _PAGE_GUARDED) == NULL)
173 		return -ENOMEM;
174 
175 	/* Fixup hose IO resource */
176 	io_virt_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
177 	hose->io_resource.start += io_virt_offset;
178 	hose->io_resource.end += io_virt_offset;
179 
180 	pr_debug("  hose->io_resource=%pR\n", &hose->io_resource);
181 
182 	return 0;
183 }
184 
185 int __devinit pcibios_map_io_space(struct pci_bus *bus)
186 {
187 	WARN_ON(bus == NULL);
188 
189 	/* If this not a PHB, nothing to do, page tables still exist and
190 	 * thus HPTEs will be faulted in when needed
191 	 */
192 	if (bus->self) {
193 		pr_debug("IO mapping for PCI-PCI bridge %s\n",
194 			 pci_name(bus->self));
195 		pr_debug("  virt=0x%016llx...0x%016llx\n",
196 			 bus->resource[0]->start + _IO_BASE,
197 			 bus->resource[0]->end + _IO_BASE);
198 		return 0;
199 	}
200 
201 	return pcibios_map_phb_io_space(pci_bus_to_host(bus));
202 }
203 EXPORT_SYMBOL_GPL(pcibios_map_io_space);
204 
205 void __devinit pcibios_setup_phb_io_space(struct pci_controller *hose)
206 {
207 	pcibios_map_phb_io_space(hose);
208 }
209 
210 #define IOBASE_BRIDGE_NUMBER	0
211 #define IOBASE_MEMORY		1
212 #define IOBASE_IO		2
213 #define IOBASE_ISA_IO		3
214 #define IOBASE_ISA_MEM		4
215 
216 long sys_pciconfig_iobase(long which, unsigned long in_bus,
217 			  unsigned long in_devfn)
218 {
219 	struct pci_controller* hose;
220 	struct list_head *ln;
221 	struct pci_bus *bus = NULL;
222 	struct device_node *hose_node;
223 
224 	/* Argh ! Please forgive me for that hack, but that's the
225 	 * simplest way to get existing XFree to not lockup on some
226 	 * G5 machines... So when something asks for bus 0 io base
227 	 * (bus 0 is HT root), we return the AGP one instead.
228 	 */
229 	if (in_bus == 0 && of_machine_is_compatible("MacRISC4")) {
230 		struct device_node *agp;
231 
232 		agp = of_find_compatible_node(NULL, NULL, "u3-agp");
233 		if (agp)
234 			in_bus = 0xf0;
235 		of_node_put(agp);
236 	}
237 
238 	/* That syscall isn't quite compatible with PCI domains, but it's
239 	 * used on pre-domains setup. We return the first match
240 	 */
241 
242 	for (ln = pci_root_buses.next; ln != &pci_root_buses; ln = ln->next) {
243 		bus = pci_bus_b(ln);
244 		if (in_bus >= bus->number && in_bus <= bus->subordinate)
245 			break;
246 		bus = NULL;
247 	}
248 	if (bus == NULL || bus->dev.of_node == NULL)
249 		return -ENODEV;
250 
251 	hose_node = bus->dev.of_node;
252 	hose = PCI_DN(hose_node)->phb;
253 
254 	switch (which) {
255 	case IOBASE_BRIDGE_NUMBER:
256 		return (long)hose->first_busno;
257 	case IOBASE_MEMORY:
258 		return (long)hose->pci_mem_offset;
259 	case IOBASE_IO:
260 		return (long)hose->io_base_phys;
261 	case IOBASE_ISA_IO:
262 		return (long)isa_io_base;
263 	case IOBASE_ISA_MEM:
264 		return -EINVAL;
265 	}
266 
267 	return -EOPNOTSUPP;
268 }
269 
270 #ifdef CONFIG_NUMA
271 int pcibus_to_node(struct pci_bus *bus)
272 {
273 	struct pci_controller *phb = pci_bus_to_host(bus);
274 	return phb->node;
275 }
276 EXPORT_SYMBOL(pcibus_to_node);
277 #endif
278