1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Common pmac/prep/chrp pci routines. -- Cort
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/pci.h>
8 #include <linux/delay.h>
9 #include <linux/string.h>
10 #include <linux/init.h>
11 #include <linux/capability.h>
12 #include <linux/sched.h>
13 #include <linux/errno.h>
14 #include <linux/memblock.h>
15 #include <linux/syscalls.h>
16 #include <linux/irq.h>
17 #include <linux/list.h>
18 #include <linux/of.h>
19 #include <linux/slab.h>
20 #include <linux/export.h>
21
22 #include <asm/processor.h>
23 #include <asm/io.h>
24 #include <asm/sections.h>
25 #include <asm/pci-bridge.h>
26 #include <asm/ppc-pci.h>
27 #include <asm/byteorder.h>
28 #include <linux/uaccess.h>
29 #include <asm/machdep.h>
30
31 #undef DEBUG
32
33 unsigned long isa_io_base = 0;
34 unsigned long pci_dram_offset = 0;
35 int pcibios_assign_bus_offset = 1;
36 EXPORT_SYMBOL(isa_io_base);
37 EXPORT_SYMBOL(pci_dram_offset);
38
39 void __init pcibios_make_OF_bus_map(void);
40
41 static void fixup_cpc710_pci64(struct pci_dev* dev);
42 static u8* pci_to_OF_bus_map;
43
44 /* By default, we don't re-assign bus numbers. We do this only on
45 * some pmacs
46 */
47 static int pci_assign_all_buses;
48
49 static int pci_bus_count;
50
51 /* This will remain NULL for now, until isa-bridge.c is made common
52 * to both 32-bit and 64-bit.
53 */
54 struct pci_dev *isa_bridge_pcidev;
55 EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
56
57 static void
fixup_cpc710_pci64(struct pci_dev * dev)58 fixup_cpc710_pci64(struct pci_dev* dev)
59 {
60 /* Hide the PCI64 BARs from the kernel as their content doesn't
61 * fit well in the resource management
62 */
63 dev->resource[0].start = dev->resource[0].end = 0;
64 dev->resource[0].flags = 0;
65 dev->resource[1].start = dev->resource[1].end = 0;
66 dev->resource[1].flags = 0;
67 }
68 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_CPC710_PCI64, fixup_cpc710_pci64);
69
70 /*
71 * Functions below are used on OpenFirmware machines.
72 */
73 static void
make_one_node_map(struct device_node * node,u8 pci_bus)74 make_one_node_map(struct device_node* node, u8 pci_bus)
75 {
76 const int *bus_range;
77 int len;
78
79 if (pci_bus >= pci_bus_count)
80 return;
81 bus_range = of_get_property(node, "bus-range", &len);
82 if (bus_range == NULL || len < 2 * sizeof(int)) {
83 printk(KERN_WARNING "Can't get bus-range for %pOF, "
84 "assuming it starts at 0\n", node);
85 pci_to_OF_bus_map[pci_bus] = 0;
86 } else
87 pci_to_OF_bus_map[pci_bus] = bus_range[0];
88
89 for_each_child_of_node(node, node) {
90 struct pci_dev* dev;
91 const unsigned int *class_code, *reg;
92
93 class_code = of_get_property(node, "class-code", NULL);
94 if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
95 (*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
96 continue;
97 reg = of_get_property(node, "reg", NULL);
98 if (!reg)
99 continue;
100 dev = pci_get_domain_bus_and_slot(0, pci_bus,
101 ((reg[0] >> 8) & 0xff));
102 if (!dev || !dev->subordinate) {
103 pci_dev_put(dev);
104 continue;
105 }
106 make_one_node_map(node, dev->subordinate->number);
107 pci_dev_put(dev);
108 }
109 }
110
111 void __init
pcibios_make_OF_bus_map(void)112 pcibios_make_OF_bus_map(void)
113 {
114 int i;
115 struct pci_controller *hose, *tmp;
116 struct property *map_prop;
117 struct device_node *dn;
118
119 pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
120 if (!pci_to_OF_bus_map) {
121 printk(KERN_ERR "Can't allocate OF bus map !\n");
122 return;
123 }
124
125 /* We fill the bus map with invalid values, that helps
126 * debugging.
127 */
128 for (i=0; i<pci_bus_count; i++)
129 pci_to_OF_bus_map[i] = 0xff;
130
131 /* For each hose, we begin searching bridges */
132 list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
133 struct device_node* node = hose->dn;
134
135 if (!node)
136 continue;
137 make_one_node_map(node, hose->first_busno);
138 }
139 dn = of_find_node_by_path("/");
140 map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
141 if (map_prop) {
142 BUG_ON(pci_bus_count > map_prop->length);
143 memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
144 }
145 of_node_put(dn);
146 #ifdef DEBUG
147 printk("PCI->OF bus map:\n");
148 for (i=0; i<pci_bus_count; i++) {
149 if (pci_to_OF_bus_map[i] == 0xff)
150 continue;
151 printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
152 }
153 #endif
154 }
155
156
157 /*
158 * Returns the PCI device matching a given OF node
159 */
pci_device_from_OF_node(struct device_node * node,u8 * bus,u8 * devfn)160 int pci_device_from_OF_node(struct device_node *node, u8 *bus, u8 *devfn)
161 {
162 struct pci_dev *dev = NULL;
163 const __be32 *reg;
164 int size;
165
166 /* Check if it might have a chance to be a PCI device */
167 if (!pci_find_hose_for_OF_device(node))
168 return -ENODEV;
169
170 reg = of_get_property(node, "reg", &size);
171 if (!reg || size < 5 * sizeof(u32))
172 return -ENODEV;
173
174 *bus = (be32_to_cpup(®[0]) >> 16) & 0xff;
175 *devfn = (be32_to_cpup(®[0]) >> 8) & 0xff;
176
177 /* Ok, here we need some tweak. If we have already renumbered
178 * all busses, we can't rely on the OF bus number any more.
179 * the pci_to_OF_bus_map is not enough as several PCI busses
180 * may match the same OF bus number.
181 */
182 if (!pci_to_OF_bus_map)
183 return 0;
184
185 for_each_pci_dev(dev)
186 if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
187 dev->devfn == *devfn) {
188 *bus = dev->bus->number;
189 pci_dev_put(dev);
190 return 0;
191 }
192
193 return -ENODEV;
194 }
195 EXPORT_SYMBOL(pci_device_from_OF_node);
196
197 /* We create the "pci-OF-bus-map" property now so it appears in the
198 * /proc device tree
199 */
200 void __init
pci_create_OF_bus_map(void)201 pci_create_OF_bus_map(void)
202 {
203 struct property* of_prop;
204 struct device_node *dn;
205
206 of_prop = memblock_alloc(sizeof(struct property) + 256,
207 SMP_CACHE_BYTES);
208 if (!of_prop)
209 panic("%s: Failed to allocate %zu bytes\n", __func__,
210 sizeof(struct property) + 256);
211 dn = of_find_node_by_path("/");
212 if (dn) {
213 memset(of_prop, -1, sizeof(struct property) + 256);
214 of_prop->name = "pci-OF-bus-map";
215 of_prop->length = 256;
216 of_prop->value = &of_prop[1];
217 of_add_property(dn, of_prop);
218 of_node_put(dn);
219 }
220 }
221
pcibios_setup_phb_io_space(struct pci_controller * hose)222 void pcibios_setup_phb_io_space(struct pci_controller *hose)
223 {
224 unsigned long io_offset;
225 struct resource *res = &hose->io_resource;
226
227 /* Fixup IO space offset */
228 io_offset = pcibios_io_space_offset(hose);
229 res->start += io_offset;
230 res->end += io_offset;
231 }
232
pcibios_init(void)233 static int __init pcibios_init(void)
234 {
235 struct pci_controller *hose, *tmp;
236 int next_busno = 0;
237
238 printk(KERN_INFO "PCI: Probing PCI hardware\n");
239
240 if (pci_has_flag(PCI_REASSIGN_ALL_BUS))
241 pci_assign_all_buses = 1;
242
243 /* Scan all of the recorded PCI controllers. */
244 list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
245 if (pci_assign_all_buses)
246 hose->first_busno = next_busno;
247 hose->last_busno = 0xff;
248 pcibios_scan_phb(hose);
249 pci_bus_add_devices(hose->bus);
250 if (pci_assign_all_buses || next_busno <= hose->last_busno)
251 next_busno = hose->last_busno + pcibios_assign_bus_offset;
252 }
253 pci_bus_count = next_busno;
254
255 /* OpenFirmware based machines need a map of OF bus
256 * numbers vs. kernel bus numbers since we may have to
257 * remap them.
258 */
259 if (pci_assign_all_buses)
260 pcibios_make_OF_bus_map();
261
262 /* Call common code to handle resource allocation */
263 pcibios_resource_survey();
264
265 /* Call machine dependent fixup */
266 if (ppc_md.pcibios_fixup)
267 ppc_md.pcibios_fixup();
268
269 /* Call machine dependent post-init code */
270 if (ppc_md.pcibios_after_init)
271 ppc_md.pcibios_after_init();
272
273 return 0;
274 }
275
276 subsys_initcall(pcibios_init);
277
278 static struct pci_controller*
pci_bus_to_hose(int bus)279 pci_bus_to_hose(int bus)
280 {
281 struct pci_controller *hose, *tmp;
282
283 list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
284 if (bus >= hose->first_busno && bus <= hose->last_busno)
285 return hose;
286 return NULL;
287 }
288
289 /* Provide information on locations of various I/O regions in physical
290 * memory. Do this on a per-card basis so that we choose the right
291 * root bridge.
292 * Note that the returned IO or memory base is a physical address
293 */
294
SYSCALL_DEFINE3(pciconfig_iobase,long,which,unsigned long,bus,unsigned long,devfn)295 SYSCALL_DEFINE3(pciconfig_iobase, long, which,
296 unsigned long, bus, unsigned long, devfn)
297 {
298 struct pci_controller* hose;
299 long result = -EOPNOTSUPP;
300
301 hose = pci_bus_to_hose(bus);
302 if (!hose)
303 return -ENODEV;
304
305 switch (which) {
306 case IOBASE_BRIDGE_NUMBER:
307 return (long)hose->first_busno;
308 case IOBASE_MEMORY:
309 return (long)hose->mem_offset[0];
310 case IOBASE_IO:
311 return (long)hose->io_base_phys;
312 case IOBASE_ISA_IO:
313 return (long)isa_io_base;
314 case IOBASE_ISA_MEM:
315 return (long)isa_mem_base;
316 }
317
318 return result;
319 }
320