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/prom.h>
25 #include <asm/sections.h>
26 #include <asm/pci-bridge.h>
27 #include <asm/ppc-pci.h>
28 #include <asm/byteorder.h>
29 #include <linux/uaccess.h>
30 #include <asm/machdep.h>
31
32 #undef DEBUG
33
34 unsigned long isa_io_base = 0;
35 unsigned long pci_dram_offset = 0;
36 int pcibios_assign_bus_offset = 1;
37 EXPORT_SYMBOL(isa_io_base);
38 EXPORT_SYMBOL(pci_dram_offset);
39
40 void pcibios_make_OF_bus_map(void);
41
42 static void fixup_cpc710_pci64(struct pci_dev* dev);
43 static u8* pci_to_OF_bus_map;
44
45 /* By default, we don't re-assign bus numbers. We do this only on
46 * some pmacs
47 */
48 static int pci_assign_all_buses;
49
50 static int pci_bus_count;
51
52 /* This will remain NULL for now, until isa-bridge.c is made common
53 * to both 32-bit and 64-bit.
54 */
55 struct pci_dev *isa_bridge_pcidev;
56 EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
57
58 static void
fixup_cpc710_pci64(struct pci_dev * dev)59 fixup_cpc710_pci64(struct pci_dev* dev)
60 {
61 /* Hide the PCI64 BARs from the kernel as their content doesn't
62 * fit well in the resource management
63 */
64 dev->resource[0].start = dev->resource[0].end = 0;
65 dev->resource[0].flags = 0;
66 dev->resource[1].start = dev->resource[1].end = 0;
67 dev->resource[1].flags = 0;
68 }
69 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_CPC710_PCI64, fixup_cpc710_pci64);
70
71 /*
72 * Functions below are used on OpenFirmware machines.
73 */
74 static void
make_one_node_map(struct device_node * node,u8 pci_bus)75 make_one_node_map(struct device_node* node, u8 pci_bus)
76 {
77 const int *bus_range;
78 int len;
79
80 if (pci_bus >= pci_bus_count)
81 return;
82 bus_range = of_get_property(node, "bus-range", &len);
83 if (bus_range == NULL || len < 2 * sizeof(int)) {
84 printk(KERN_WARNING "Can't get bus-range for %pOF, "
85 "assuming it starts at 0\n", node);
86 pci_to_OF_bus_map[pci_bus] = 0;
87 } else
88 pci_to_OF_bus_map[pci_bus] = bus_range[0];
89
90 for_each_child_of_node(node, node) {
91 struct pci_dev* dev;
92 const unsigned int *class_code, *reg;
93
94 class_code = of_get_property(node, "class-code", NULL);
95 if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
96 (*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
97 continue;
98 reg = of_get_property(node, "reg", NULL);
99 if (!reg)
100 continue;
101 dev = pci_get_domain_bus_and_slot(0, pci_bus,
102 ((reg[0] >> 8) & 0xff));
103 if (!dev || !dev->subordinate) {
104 pci_dev_put(dev);
105 continue;
106 }
107 make_one_node_map(node, dev->subordinate->number);
108 pci_dev_put(dev);
109 }
110 }
111
112 void
pcibios_make_OF_bus_map(void)113 pcibios_make_OF_bus_map(void)
114 {
115 int i;
116 struct pci_controller *hose, *tmp;
117 struct property *map_prop;
118 struct device_node *dn;
119
120 pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
121 if (!pci_to_OF_bus_map) {
122 printk(KERN_ERR "Can't allocate OF bus map !\n");
123 return;
124 }
125
126 /* We fill the bus map with invalid values, that helps
127 * debugging.
128 */
129 for (i=0; i<pci_bus_count; i++)
130 pci_to_OF_bus_map[i] = 0xff;
131
132 /* For each hose, we begin searching bridges */
133 list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
134 struct device_node* node = hose->dn;
135
136 if (!node)
137 continue;
138 make_one_node_map(node, hose->first_busno);
139 }
140 dn = of_find_node_by_path("/");
141 map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
142 if (map_prop) {
143 BUG_ON(pci_bus_count > map_prop->length);
144 memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
145 }
146 of_node_put(dn);
147 #ifdef DEBUG
148 printk("PCI->OF bus map:\n");
149 for (i=0; i<pci_bus_count; i++) {
150 if (pci_to_OF_bus_map[i] == 0xff)
151 continue;
152 printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
153 }
154 #endif
155 }
156
157
158 /*
159 * Returns the PCI device matching a given OF node
160 */
pci_device_from_OF_node(struct device_node * node,u8 * bus,u8 * devfn)161 int pci_device_from_OF_node(struct device_node *node, u8 *bus, u8 *devfn)
162 {
163 struct pci_dev *dev = NULL;
164 const __be32 *reg;
165 int size;
166
167 /* Check if it might have a chance to be a PCI device */
168 if (!pci_find_hose_for_OF_device(node))
169 return -ENODEV;
170
171 reg = of_get_property(node, "reg", &size);
172 if (!reg || size < 5 * sizeof(u32))
173 return -ENODEV;
174
175 *bus = (be32_to_cpup(®[0]) >> 16) & 0xff;
176 *devfn = (be32_to_cpup(®[0]) >> 8) & 0xff;
177
178 /* Ok, here we need some tweak. If we have already renumbered
179 * all busses, we can't rely on the OF bus number any more.
180 * the pci_to_OF_bus_map is not enough as several PCI busses
181 * may match the same OF bus number.
182 */
183 if (!pci_to_OF_bus_map)
184 return 0;
185
186 for_each_pci_dev(dev)
187 if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
188 dev->devfn == *devfn) {
189 *bus = dev->bus->number;
190 pci_dev_put(dev);
191 return 0;
192 }
193
194 return -ENODEV;
195 }
196 EXPORT_SYMBOL(pci_device_from_OF_node);
197
198 /* We create the "pci-OF-bus-map" property now so it appears in the
199 * /proc device tree
200 */
201 void __init
pci_create_OF_bus_map(void)202 pci_create_OF_bus_map(void)
203 {
204 struct property* of_prop;
205 struct device_node *dn;
206
207 of_prop = memblock_alloc(sizeof(struct property) + 256,
208 SMP_CACHE_BYTES);
209 if (!of_prop)
210 panic("%s: Failed to allocate %zu bytes\n", __func__,
211 sizeof(struct property) + 256);
212 dn = of_find_node_by_path("/");
213 if (dn) {
214 memset(of_prop, -1, sizeof(struct property) + 256);
215 of_prop->name = "pci-OF-bus-map";
216 of_prop->length = 256;
217 of_prop->value = &of_prop[1];
218 of_add_property(dn, of_prop);
219 of_node_put(dn);
220 }
221 }
222
pcibios_setup_phb_io_space(struct pci_controller * hose)223 void pcibios_setup_phb_io_space(struct pci_controller *hose)
224 {
225 unsigned long io_offset;
226 struct resource *res = &hose->io_resource;
227
228 /* Fixup IO space offset */
229 io_offset = pcibios_io_space_offset(hose);
230 res->start += io_offset;
231 res->end += io_offset;
232 }
233
pcibios_init(void)234 static int __init pcibios_init(void)
235 {
236 struct pci_controller *hose, *tmp;
237 int next_busno = 0;
238
239 printk(KERN_INFO "PCI: Probing PCI hardware\n");
240
241 if (pci_has_flag(PCI_REASSIGN_ALL_BUS))
242 pci_assign_all_buses = 1;
243
244 /* Scan all of the recorded PCI controllers. */
245 list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
246 if (pci_assign_all_buses)
247 hose->first_busno = next_busno;
248 hose->last_busno = 0xff;
249 pcibios_scan_phb(hose);
250 pci_bus_add_devices(hose->bus);
251 if (pci_assign_all_buses || next_busno <= hose->last_busno)
252 next_busno = hose->last_busno + pcibios_assign_bus_offset;
253 }
254 pci_bus_count = next_busno;
255
256 /* OpenFirmware based machines need a map of OF bus
257 * numbers vs. kernel bus numbers since we may have to
258 * remap them.
259 */
260 if (pci_assign_all_buses)
261 pcibios_make_OF_bus_map();
262
263 /* Call common code to handle resource allocation */
264 pcibios_resource_survey();
265
266 /* Call machine dependent fixup */
267 if (ppc_md.pcibios_fixup)
268 ppc_md.pcibios_fixup();
269
270 /* Call machine dependent post-init code */
271 if (ppc_md.pcibios_after_init)
272 ppc_md.pcibios_after_init();
273
274 return 0;
275 }
276
277 subsys_initcall(pcibios_init);
278
279 static struct pci_controller*
pci_bus_to_hose(int bus)280 pci_bus_to_hose(int bus)
281 {
282 struct pci_controller *hose, *tmp;
283
284 list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
285 if (bus >= hose->first_busno && bus <= hose->last_busno)
286 return hose;
287 return NULL;
288 }
289
290 /* Provide information on locations of various I/O regions in physical
291 * memory. Do this on a per-card basis so that we choose the right
292 * root bridge.
293 * Note that the returned IO or memory base is a physical address
294 */
295
SYSCALL_DEFINE3(pciconfig_iobase,long,which,unsigned long,bus,unsigned long,devfn)296 SYSCALL_DEFINE3(pciconfig_iobase, long, which,
297 unsigned long, bus, unsigned long, devfn)
298 {
299 struct pci_controller* hose;
300 long result = -EOPNOTSUPP;
301
302 hose = pci_bus_to_hose(bus);
303 if (!hose)
304 return -ENODEV;
305
306 switch (which) {
307 case IOBASE_BRIDGE_NUMBER:
308 return (long)hose->first_busno;
309 case IOBASE_MEMORY:
310 return (long)hose->mem_offset[0];
311 case IOBASE_IO:
312 return (long)hose->io_base_phys;
313 case IOBASE_ISA_IO:
314 return (long)isa_io_base;
315 case IOBASE_ISA_MEM:
316 return (long)isa_mem_base;
317 }
318
319 return result;
320 }
321