xref: /openbmc/linux/arch/powerpc/kernel/pci_64.c (revision 93f5715e)
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/export.h>
21 #include <linux/mm.h>
22 #include <linux/list.h>
23 #include <linux/syscalls.h>
24 #include <linux/irq.h>
25 #include <linux/vmalloc.h>
26 
27 #include <asm/processor.h>
28 #include <asm/io.h>
29 #include <asm/prom.h>
30 #include <asm/pci-bridge.h>
31 #include <asm/byteorder.h>
32 #include <asm/machdep.h>
33 #include <asm/ppc-pci.h>
34 
35 /* pci_io_base -- the base address from which io bars are offsets.
36  * This is the lowest I/O base address (so bar values are always positive),
37  * and it *must* be the start of ISA space if an ISA bus exists because
38  * ISA drivers use hard coded offsets.  If no ISA bus exists nothing
39  * is mapped on the first 64K of IO space
40  */
41 unsigned long pci_io_base;
42 EXPORT_SYMBOL(pci_io_base);
43 
44 static int __init pcibios_init(void)
45 {
46 	struct pci_controller *hose, *tmp;
47 
48 	printk(KERN_INFO "PCI: Probing PCI hardware\n");
49 
50 	/* For now, override phys_mem_access_prot. If we need it,g
51 	 * later, we may move that initialization to each ppc_md
52 	 */
53 	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;
54 
55 	/* On ppc64, we always enable PCI domains and we keep domain 0
56 	 * backward compatible in /proc for video cards
57 	 */
58 	pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);
59 
60 	/* Scan all of the recorded PCI controllers.  */
61 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
62 		pcibios_scan_phb(hose);
63 		pci_bus_add_devices(hose->bus);
64 	}
65 
66 	/* Call common code to handle resource allocation */
67 	pcibios_resource_survey();
68 
69 	printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");
70 
71 	return 0;
72 }
73 
74 subsys_initcall(pcibios_init);
75 
76 int pcibios_unmap_io_space(struct pci_bus *bus)
77 {
78 	struct pci_controller *hose;
79 
80 	WARN_ON(bus == NULL);
81 
82 	/* If this is not a PHB, we only flush the hash table over
83 	 * the area mapped by this bridge. We don't play with the PTE
84 	 * mappings since we might have to deal with sub-page alignments
85 	 * so flushing the hash table is the only sane way to make sure
86 	 * that no hash entries are covering that removed bridge area
87 	 * while still allowing other busses overlapping those pages
88 	 *
89 	 * Note: If we ever support P2P hotplug on Book3E, we'll have
90 	 * to do an appropriate TLB flush here too
91 	 */
92 	if (bus->self) {
93 #ifdef CONFIG_PPC_BOOK3S_64
94 		struct resource *res = bus->resource[0];
95 #endif
96 
97 		pr_debug("IO unmapping for PCI-PCI bridge %s\n",
98 			 pci_name(bus->self));
99 
100 #ifdef CONFIG_PPC_BOOK3S_64
101 		__flush_hash_table_range(&init_mm, res->start + _IO_BASE,
102 					 res->end + _IO_BASE + 1);
103 #endif
104 		return 0;
105 	}
106 
107 	/* Get the host bridge */
108 	hose = pci_bus_to_host(bus);
109 
110 	/* Check if we have IOs allocated */
111 	if (hose->io_base_alloc == NULL)
112 		return 0;
113 
114 	pr_debug("IO unmapping for PHB %pOF\n", hose->dn);
115 	pr_debug("  alloc=0x%p\n", hose->io_base_alloc);
116 
117 	/* This is a PHB, we fully unmap the IO area */
118 	vunmap(hose->io_base_alloc);
119 
120 	return 0;
121 }
122 EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);
123 
124 static int pcibios_map_phb_io_space(struct pci_controller *hose)
125 {
126 	struct vm_struct *area;
127 	unsigned long phys_page;
128 	unsigned long size_page;
129 	unsigned long io_virt_offset;
130 
131 	phys_page = _ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
132 	size_page = _ALIGN_UP(hose->pci_io_size, PAGE_SIZE);
133 
134 	/* Make sure IO area address is clear */
135 	hose->io_base_alloc = NULL;
136 
137 	/* If there's no IO to map on that bus, get away too */
138 	if (hose->pci_io_size == 0 || hose->io_base_phys == 0)
139 		return 0;
140 
141 	/* Let's allocate some IO space for that guy. We don't pass
142 	 * VM_IOREMAP because we don't care about alignment tricks that
143 	 * the core does in that case. Maybe we should due to stupid card
144 	 * with incomplete address decoding but I'd rather not deal with
145 	 * those outside of the reserved 64K legacy region.
146 	 */
147 	area = __get_vm_area(size_page, 0, PHB_IO_BASE, PHB_IO_END);
148 	if (area == NULL)
149 		return -ENOMEM;
150 	hose->io_base_alloc = area->addr;
151 	hose->io_base_virt = (void __iomem *)(area->addr +
152 					      hose->io_base_phys - phys_page);
153 
154 	pr_debug("IO mapping for PHB %pOF\n", hose->dn);
155 	pr_debug("  phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
156 		 hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
157 	pr_debug("  size=0x%016llx (alloc=0x%016lx)\n",
158 		 hose->pci_io_size, size_page);
159 
160 	/* Establish the mapping */
161 	if (__ioremap_at(phys_page, area->addr, size_page,
162 			 pgprot_val(pgprot_noncached(__pgprot(0)))) == NULL)
163 		return -ENOMEM;
164 
165 	/* Fixup hose IO resource */
166 	io_virt_offset = pcibios_io_space_offset(hose);
167 	hose->io_resource.start += io_virt_offset;
168 	hose->io_resource.end += io_virt_offset;
169 
170 	pr_debug("  hose->io_resource=%pR\n", &hose->io_resource);
171 
172 	return 0;
173 }
174 
175 int pcibios_map_io_space(struct pci_bus *bus)
176 {
177 	WARN_ON(bus == NULL);
178 
179 	/* If this not a PHB, nothing to do, page tables still exist and
180 	 * thus HPTEs will be faulted in when needed
181 	 */
182 	if (bus->self) {
183 		pr_debug("IO mapping for PCI-PCI bridge %s\n",
184 			 pci_name(bus->self));
185 		pr_debug("  virt=0x%016llx...0x%016llx\n",
186 			 bus->resource[0]->start + _IO_BASE,
187 			 bus->resource[0]->end + _IO_BASE);
188 		return 0;
189 	}
190 
191 	return pcibios_map_phb_io_space(pci_bus_to_host(bus));
192 }
193 EXPORT_SYMBOL_GPL(pcibios_map_io_space);
194 
195 void pcibios_setup_phb_io_space(struct pci_controller *hose)
196 {
197 	pcibios_map_phb_io_space(hose);
198 }
199 
200 #define IOBASE_BRIDGE_NUMBER	0
201 #define IOBASE_MEMORY		1
202 #define IOBASE_IO		2
203 #define IOBASE_ISA_IO		3
204 #define IOBASE_ISA_MEM		4
205 
206 SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, in_bus,
207 			  unsigned long, in_devfn)
208 {
209 	struct pci_controller* hose;
210 	struct pci_bus *tmp_bus, *bus = NULL;
211 	struct device_node *hose_node;
212 
213 	/* Argh ! Please forgive me for that hack, but that's the
214 	 * simplest way to get existing XFree to not lockup on some
215 	 * G5 machines... So when something asks for bus 0 io base
216 	 * (bus 0 is HT root), we return the AGP one instead.
217 	 */
218 	if (in_bus == 0 && of_machine_is_compatible("MacRISC4")) {
219 		struct device_node *agp;
220 
221 		agp = of_find_compatible_node(NULL, NULL, "u3-agp");
222 		if (agp)
223 			in_bus = 0xf0;
224 		of_node_put(agp);
225 	}
226 
227 	/* That syscall isn't quite compatible with PCI domains, but it's
228 	 * used on pre-domains setup. We return the first match
229 	 */
230 
231 	list_for_each_entry(tmp_bus, &pci_root_buses, node) {
232 		if (in_bus >= tmp_bus->number &&
233 		    in_bus <= tmp_bus->busn_res.end) {
234 			bus = tmp_bus;
235 			break;
236 		}
237 	}
238 	if (bus == NULL || bus->dev.of_node == NULL)
239 		return -ENODEV;
240 
241 	hose_node = bus->dev.of_node;
242 	hose = PCI_DN(hose_node)->phb;
243 
244 	switch (which) {
245 	case IOBASE_BRIDGE_NUMBER:
246 		return (long)hose->first_busno;
247 	case IOBASE_MEMORY:
248 		return (long)hose->mem_offset[0];
249 	case IOBASE_IO:
250 		return (long)hose->io_base_phys;
251 	case IOBASE_ISA_IO:
252 		return (long)isa_io_base;
253 	case IOBASE_ISA_MEM:
254 		return -EINVAL;
255 	}
256 
257 	return -EOPNOTSUPP;
258 }
259 
260 #ifdef CONFIG_NUMA
261 int pcibus_to_node(struct pci_bus *bus)
262 {
263 	struct pci_controller *phb = pci_bus_to_host(bus);
264 	return phb->node;
265 }
266 EXPORT_SYMBOL(pcibus_to_node);
267 #endif
268