xref: /openbmc/linux/arch/powerpc/kernel/pci_32.c (revision db181ce0)
1 /*
2  * Common pmac/prep/chrp pci routines. -- Cort
3  */
4 
5 #include <linux/kernel.h>
6 #include <linux/pci.h>
7 #include <linux/delay.h>
8 #include <linux/string.h>
9 #include <linux/init.h>
10 #include <linux/capability.h>
11 #include <linux/sched.h>
12 #include <linux/errno.h>
13 #include <linux/bootmem.h>
14 #include <linux/irq.h>
15 #include <linux/list.h>
16 #include <linux/of.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 
20 #include <asm/processor.h>
21 #include <asm/io.h>
22 #include <asm/prom.h>
23 #include <asm/sections.h>
24 #include <asm/pci-bridge.h>
25 #include <asm/ppc-pci.h>
26 #include <asm/byteorder.h>
27 #include <asm/uaccess.h>
28 #include <asm/machdep.h>
29 
30 #undef DEBUG
31 
32 unsigned long isa_io_base     = 0;
33 unsigned long pci_dram_offset = 0;
34 int pcibios_assign_bus_offset = 1;
35 
36 void pcibios_make_OF_bus_map(void);
37 
38 static void fixup_cpc710_pci64(struct pci_dev* dev);
39 static u8* pci_to_OF_bus_map;
40 
41 /* By default, we don't re-assign bus numbers. We do this only on
42  * some pmacs
43  */
44 static int pci_assign_all_buses;
45 
46 static int pci_bus_count;
47 
48 /* This will remain NULL for now, until isa-bridge.c is made common
49  * to both 32-bit and 64-bit.
50  */
51 struct pci_dev *isa_bridge_pcidev;
52 EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
53 
54 static void
55 fixup_cpc710_pci64(struct pci_dev* dev)
56 {
57 	/* Hide the PCI64 BARs from the kernel as their content doesn't
58 	 * fit well in the resource management
59 	 */
60 	dev->resource[0].start = dev->resource[0].end = 0;
61 	dev->resource[0].flags = 0;
62 	dev->resource[1].start = dev->resource[1].end = 0;
63 	dev->resource[1].flags = 0;
64 }
65 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM,	PCI_DEVICE_ID_IBM_CPC710_PCI64,	fixup_cpc710_pci64);
66 
67 /*
68  * Functions below are used on OpenFirmware machines.
69  */
70 static void
71 make_one_node_map(struct device_node* node, u8 pci_bus)
72 {
73 	const int *bus_range;
74 	int len;
75 
76 	if (pci_bus >= pci_bus_count)
77 		return;
78 	bus_range = of_get_property(node, "bus-range", &len);
79 	if (bus_range == NULL || len < 2 * sizeof(int)) {
80 		printk(KERN_WARNING "Can't get bus-range for %s, "
81 		       "assuming it starts at 0\n", node->full_name);
82 		pci_to_OF_bus_map[pci_bus] = 0;
83 	} else
84 		pci_to_OF_bus_map[pci_bus] = bus_range[0];
85 
86 	for_each_child_of_node(node, node) {
87 		struct pci_dev* dev;
88 		const unsigned int *class_code, *reg;
89 
90 		class_code = of_get_property(node, "class-code", NULL);
91 		if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
92 			(*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
93 			continue;
94 		reg = of_get_property(node, "reg", NULL);
95 		if (!reg)
96 			continue;
97 		dev = pci_get_bus_and_slot(pci_bus, ((reg[0] >> 8) & 0xff));
98 		if (!dev || !dev->subordinate) {
99 			pci_dev_put(dev);
100 			continue;
101 		}
102 		make_one_node_map(node, dev->subordinate->number);
103 		pci_dev_put(dev);
104 	}
105 }
106 
107 void
108 pcibios_make_OF_bus_map(void)
109 {
110 	int i;
111 	struct pci_controller *hose, *tmp;
112 	struct property *map_prop;
113 	struct device_node *dn;
114 
115 	pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
116 	if (!pci_to_OF_bus_map) {
117 		printk(KERN_ERR "Can't allocate OF bus map !\n");
118 		return;
119 	}
120 
121 	/* We fill the bus map with invalid values, that helps
122 	 * debugging.
123 	 */
124 	for (i=0; i<pci_bus_count; i++)
125 		pci_to_OF_bus_map[i] = 0xff;
126 
127 	/* For each hose, we begin searching bridges */
128 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
129 		struct device_node* node = hose->dn;
130 
131 		if (!node)
132 			continue;
133 		make_one_node_map(node, hose->first_busno);
134 	}
135 	dn = of_find_node_by_path("/");
136 	map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
137 	if (map_prop) {
138 		BUG_ON(pci_bus_count > map_prop->length);
139 		memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
140 	}
141 	of_node_put(dn);
142 #ifdef DEBUG
143 	printk("PCI->OF bus map:\n");
144 	for (i=0; i<pci_bus_count; i++) {
145 		if (pci_to_OF_bus_map[i] == 0xff)
146 			continue;
147 		printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
148 	}
149 #endif
150 }
151 
152 
153 /*
154  * Returns the PCI device matching a given OF node
155  */
156 int pci_device_from_OF_node(struct device_node *node, u8 *bus, u8 *devfn)
157 {
158 	struct pci_dev *dev = NULL;
159 	const __be32 *reg;
160 	int size;
161 
162 	/* Check if it might have a chance to be a PCI device */
163 	if (!pci_find_hose_for_OF_device(node))
164 		return -ENODEV;
165 
166 	reg = of_get_property(node, "reg", &size);
167 	if (!reg || size < 5 * sizeof(u32))
168 		return -ENODEV;
169 
170 	*bus = (be32_to_cpup(&reg[0]) >> 16) & 0xff;
171 	*devfn = (be32_to_cpup(&reg[0]) >> 8) & 0xff;
172 
173 	/* Ok, here we need some tweak. If we have already renumbered
174 	 * all busses, we can't rely on the OF bus number any more.
175 	 * the pci_to_OF_bus_map is not enough as several PCI busses
176 	 * may match the same OF bus number.
177 	 */
178 	if (!pci_to_OF_bus_map)
179 		return 0;
180 
181 	for_each_pci_dev(dev)
182 		if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
183 				dev->devfn == *devfn) {
184 			*bus = dev->bus->number;
185 			pci_dev_put(dev);
186 			return 0;
187 		}
188 
189 	return -ENODEV;
190 }
191 EXPORT_SYMBOL(pci_device_from_OF_node);
192 
193 /* We create the "pci-OF-bus-map" property now so it appears in the
194  * /proc device tree
195  */
196 void __init
197 pci_create_OF_bus_map(void)
198 {
199 	struct property* of_prop;
200 	struct device_node *dn;
201 
202 	of_prop = (struct property*) alloc_bootmem(sizeof(struct property) + 256);
203 	if (!of_prop)
204 		return;
205 	dn = of_find_node_by_path("/");
206 	if (dn) {
207 		memset(of_prop, -1, sizeof(struct property) + 256);
208 		of_prop->name = "pci-OF-bus-map";
209 		of_prop->length = 256;
210 		of_prop->value = &of_prop[1];
211 		of_add_property(dn, of_prop);
212 		of_node_put(dn);
213 	}
214 }
215 
216 void pcibios_setup_phb_io_space(struct pci_controller *hose)
217 {
218 	unsigned long io_offset;
219 	struct resource *res = &hose->io_resource;
220 
221 	/* Fixup IO space offset */
222 	io_offset = pcibios_io_space_offset(hose);
223 	res->start += io_offset;
224 	res->end += io_offset;
225 }
226 
227 static int __init pcibios_init(void)
228 {
229 	struct pci_controller *hose, *tmp;
230 	int next_busno = 0;
231 
232 	printk(KERN_INFO "PCI: Probing PCI hardware\n");
233 
234 	if (pci_has_flag(PCI_REASSIGN_ALL_BUS))
235 		pci_assign_all_buses = 1;
236 
237 	/* Scan all of the recorded PCI controllers.  */
238 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
239 		if (pci_assign_all_buses)
240 			hose->first_busno = next_busno;
241 		hose->last_busno = 0xff;
242 		pcibios_scan_phb(hose);
243 		pci_bus_add_devices(hose->bus);
244 		if (pci_assign_all_buses || next_busno <= hose->last_busno)
245 			next_busno = hose->last_busno + pcibios_assign_bus_offset;
246 	}
247 	pci_bus_count = next_busno;
248 
249 	/* OpenFirmware based machines need a map of OF bus
250 	 * numbers vs. kernel bus numbers since we may have to
251 	 * remap them.
252 	 */
253 	if (pci_assign_all_buses)
254 		pcibios_make_OF_bus_map();
255 
256 	/* Call common code to handle resource allocation */
257 	pcibios_resource_survey();
258 
259 	/* Call machine dependent post-init code */
260 	if (ppc_md.pcibios_after_init)
261 		ppc_md.pcibios_after_init();
262 
263 	return 0;
264 }
265 
266 subsys_initcall(pcibios_init);
267 
268 static struct pci_controller*
269 pci_bus_to_hose(int bus)
270 {
271 	struct pci_controller *hose, *tmp;
272 
273 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
274 		if (bus >= hose->first_busno && bus <= hose->last_busno)
275 			return hose;
276 	return NULL;
277 }
278 
279 /* Provide information on locations of various I/O regions in physical
280  * memory.  Do this on a per-card basis so that we choose the right
281  * root bridge.
282  * Note that the returned IO or memory base is a physical address
283  */
284 
285 long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
286 {
287 	struct pci_controller* hose;
288 	long result = -EOPNOTSUPP;
289 
290 	hose = pci_bus_to_hose(bus);
291 	if (!hose)
292 		return -ENODEV;
293 
294 	switch (which) {
295 	case IOBASE_BRIDGE_NUMBER:
296 		return (long)hose->first_busno;
297 	case IOBASE_MEMORY:
298 		return (long)hose->mem_offset[0];
299 	case IOBASE_IO:
300 		return (long)hose->io_base_phys;
301 	case IOBASE_ISA_IO:
302 		return (long)isa_io_base;
303 	case IOBASE_ISA_MEM:
304 		return (long)isa_mem_base;
305 	}
306 
307 	return result;
308 }
309 
310 
311