xref: /openbmc/u-boot/drivers/pci/pci_auto.c (revision 0e8d1586)
1 /*
2  * arch/ppc/kernel/pci_auto.c
3  *
4  * PCI autoconfiguration library
5  *
6  * Author: Matt Porter <mporter@mvista.com>
7  *
8  * Copyright 2000 MontaVista Software Inc.
9  *
10  * This program is free software; you can redistribute  it and/or modify it
11  * under  the terms of  the GNU General  Public License as published by the
12  * Free Software Foundation;  either version 2 of the  License, or (at your
13  * option) any later version.
14  */
15 
16 #include <common.h>
17 
18 #include <pci.h>
19 
20 #undef DEBUG
21 #ifdef DEBUG
22 #define DEBUGF(x...) printf(x)
23 #else
24 #define DEBUGF(x...)
25 #endif /* DEBUG */
26 
27 #define	PCIAUTO_IDE_MODE_MASK		0x05
28 
29 /* the user can define CFG_PCI_CACHE_LINE_SIZE to avoid problems */
30 #ifndef CFG_PCI_CACHE_LINE_SIZE
31 #define CFG_PCI_CACHE_LINE_SIZE	8
32 #endif
33 
34 /*
35  *
36  */
37 
38 void pciauto_region_init(struct pci_region* res)
39 {
40 	/*
41 	 * Avoid allocating PCI resources from address 0 -- this is illegal
42 	 * according to PCI 2.1 and moreover, this is known to cause Linux IDE
43 	 * drivers to fail. Use a reasonable starting value of 0x1000 instead.
44 	 */
45 	res->bus_lower = res->bus_start ? res->bus_start : 0x1000;
46 }
47 
48 void pciauto_region_align(struct pci_region *res, unsigned long size)
49 {
50 	res->bus_lower = ((res->bus_lower - 1) | (size - 1)) + 1;
51 }
52 
53 int pciauto_region_allocate(struct pci_region* res, unsigned int size, unsigned int *bar)
54 {
55 	unsigned long addr;
56 
57 	if (!res) {
58 		DEBUGF("No resource");
59 		goto error;
60 	}
61 
62 	addr = ((res->bus_lower - 1) | (size - 1)) + 1;
63 
64 	if (addr - res->bus_start + size > res->size) {
65 		DEBUGF("No room in resource");
66 		goto error;
67 	}
68 
69 	res->bus_lower = addr + size;
70 
71 	DEBUGF("address=0x%lx bus_lower=%x", addr, res->bus_lower);
72 
73 	*bar = addr;
74 	return 0;
75 
76  error:
77 	*bar = 0xffffffff;
78 	return -1;
79 }
80 
81 /*
82  *
83  */
84 
85 void pciauto_setup_device(struct pci_controller *hose,
86 			  pci_dev_t dev, int bars_num,
87 			  struct pci_region *mem,
88 			  struct pci_region *prefetch,
89 			  struct pci_region *io)
90 {
91 	unsigned int bar_value, bar_response, bar_size;
92 	unsigned int cmdstat = 0;
93 	struct pci_region *bar_res;
94 	int bar, bar_nr = 0;
95 	int found_mem64 = 0;
96 
97 	pci_hose_read_config_dword(hose, dev, PCI_COMMAND, &cmdstat);
98 	cmdstat = (cmdstat & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) | PCI_COMMAND_MASTER;
99 
100 	for (bar = PCI_BASE_ADDRESS_0; bar < PCI_BASE_ADDRESS_0 + (bars_num*4); bar += 4) {
101 		/* Tickle the BAR and get the response */
102 		pci_hose_write_config_dword(hose, dev, bar, 0xffffffff);
103 		pci_hose_read_config_dword(hose, dev, bar, &bar_response);
104 
105 		/* If BAR is not implemented go to the next BAR */
106 		if (!bar_response)
107 			continue;
108 
109 		found_mem64 = 0;
110 
111 		/* Check the BAR type and set our address mask */
112 		if (bar_response & PCI_BASE_ADDRESS_SPACE) {
113 			bar_size = ((~(bar_response & PCI_BASE_ADDRESS_IO_MASK))
114 				   & 0xffff) + 1;
115 			bar_res = io;
116 
117 			DEBUGF("PCI Autoconfig: BAR %d, I/O, size=0x%x, ", bar_nr, bar_size);
118 		} else {
119 			if ( (bar_response & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
120 			     PCI_BASE_ADDRESS_MEM_TYPE_64)
121 				found_mem64 = 1;
122 
123 			bar_size = ~(bar_response & PCI_BASE_ADDRESS_MEM_MASK) + 1;
124 			if (prefetch && (bar_response & PCI_BASE_ADDRESS_MEM_PREFETCH))
125 				bar_res = prefetch;
126 			else
127 				bar_res = mem;
128 
129 			DEBUGF("PCI Autoconfig: BAR %d, Mem, size=0x%x, ", bar_nr, bar_size);
130 		}
131 
132 		if (pciauto_region_allocate(bar_res, bar_size, &bar_value) == 0) {
133 			/* Write it out and update our limit */
134 			pci_hose_write_config_dword(hose, dev, bar, bar_value);
135 
136 			/*
137 			 * If we are a 64-bit decoder then increment to the
138 			 * upper 32 bits of the bar and force it to locate
139 			 * in the lower 4GB of memory.
140 			 */
141 			if (found_mem64) {
142 				bar += 4;
143 				pci_hose_write_config_dword(hose, dev, bar, 0x00000000);
144 			}
145 
146 			cmdstat |= (bar_response & PCI_BASE_ADDRESS_SPACE) ?
147 				PCI_COMMAND_IO : PCI_COMMAND_MEMORY;
148 		}
149 
150 		DEBUGF("\n");
151 
152 		bar_nr++;
153 	}
154 
155 	pci_hose_write_config_dword(hose, dev, PCI_COMMAND, cmdstat);
156 	pci_hose_write_config_byte(hose, dev, PCI_CACHE_LINE_SIZE,
157 		CFG_PCI_CACHE_LINE_SIZE);
158 	pci_hose_write_config_byte(hose, dev, PCI_LATENCY_TIMER, 0x80);
159 }
160 
161 void pciauto_prescan_setup_bridge(struct pci_controller *hose,
162 					 pci_dev_t dev, int sub_bus)
163 {
164 	struct pci_region *pci_mem = hose->pci_mem;
165 	struct pci_region *pci_prefetch = hose->pci_prefetch;
166 	struct pci_region *pci_io = hose->pci_io;
167 	unsigned int cmdstat;
168 
169 	pci_hose_read_config_dword(hose, dev, PCI_COMMAND, &cmdstat);
170 
171 	/* Configure bus number registers */
172 	pci_hose_write_config_byte(hose, dev, PCI_PRIMARY_BUS,
173 				   PCI_BUS(dev) - hose->first_busno);
174 	pci_hose_write_config_byte(hose, dev, PCI_SECONDARY_BUS,
175 				   sub_bus - hose->first_busno);
176 	pci_hose_write_config_byte(hose, dev, PCI_SUBORDINATE_BUS, 0xff);
177 
178 	if (pci_mem) {
179 		/* Round memory allocator to 1MB boundary */
180 		pciauto_region_align(pci_mem, 0x100000);
181 
182 		/* Set up memory and I/O filter limits, assume 32-bit I/O space */
183 		pci_hose_write_config_word(hose, dev, PCI_MEMORY_BASE,
184 					(pci_mem->bus_lower & 0xfff00000) >> 16);
185 
186 		cmdstat |= PCI_COMMAND_MEMORY;
187 	}
188 
189 	if (pci_prefetch) {
190 		/* Round memory allocator to 1MB boundary */
191 		pciauto_region_align(pci_prefetch, 0x100000);
192 
193 		/* Set up memory and I/O filter limits, assume 32-bit I/O space */
194 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
195 					(pci_prefetch->bus_lower & 0xfff00000) >> 16);
196 
197 		cmdstat |= PCI_COMMAND_MEMORY;
198 	} else {
199 		/* We don't support prefetchable memory for now, so disable */
200 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE, 0x1000);
201 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT, 0x0);
202 	}
203 
204 	if (pci_io) {
205 		/* Round I/O allocator to 4KB boundary */
206 		pciauto_region_align(pci_io, 0x1000);
207 
208 		pci_hose_write_config_byte(hose, dev, PCI_IO_BASE,
209 					(pci_io->bus_lower & 0x0000f000) >> 8);
210 		pci_hose_write_config_word(hose, dev, PCI_IO_BASE_UPPER16,
211 					(pci_io->bus_lower & 0xffff0000) >> 16);
212 
213 		cmdstat |= PCI_COMMAND_IO;
214 	}
215 
216 	/* Enable memory and I/O accesses, enable bus master */
217 	pci_hose_write_config_dword(hose, dev, PCI_COMMAND, cmdstat | PCI_COMMAND_MASTER);
218 }
219 
220 void pciauto_postscan_setup_bridge(struct pci_controller *hose,
221 					  pci_dev_t dev, int sub_bus)
222 {
223 	struct pci_region *pci_mem = hose->pci_mem;
224 	struct pci_region *pci_prefetch = hose->pci_prefetch;
225 	struct pci_region *pci_io = hose->pci_io;
226 
227 	/* Configure bus number registers */
228 	pci_hose_write_config_byte(hose, dev, PCI_SUBORDINATE_BUS,
229 				   sub_bus - hose->first_busno);
230 
231 	if (pci_mem) {
232 		/* Round memory allocator to 1MB boundary */
233 		pciauto_region_align(pci_mem, 0x100000);
234 
235 		pci_hose_write_config_word(hose, dev, PCI_MEMORY_LIMIT,
236 					(pci_mem->bus_lower-1) >> 16);
237 	}
238 
239 	if (pci_prefetch) {
240 		/* Round memory allocator to 1MB boundary */
241 		pciauto_region_align(pci_prefetch, 0x100000);
242 
243 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT,
244 					(pci_prefetch->bus_lower-1) >> 16);
245 	}
246 
247 	if (pci_io) {
248 		/* Round I/O allocator to 4KB boundary */
249 		pciauto_region_align(pci_io, 0x1000);
250 
251 		pci_hose_write_config_byte(hose, dev, PCI_IO_LIMIT,
252 					((pci_io->bus_lower-1) & 0x0000f000) >> 8);
253 		pci_hose_write_config_word(hose, dev, PCI_IO_LIMIT_UPPER16,
254 					((pci_io->bus_lower-1) & 0xffff0000) >> 16);
255 	}
256 }
257 
258 /*
259  *
260  */
261 
262 void pciauto_config_init(struct pci_controller *hose)
263 {
264 	int i;
265 
266 	hose->pci_io = hose->pci_mem = NULL;
267 
268 	for (i=0; i<hose->region_count; i++) {
269 		switch(hose->regions[i].flags) {
270 		case PCI_REGION_IO:
271 			if (!hose->pci_io ||
272 			    hose->pci_io->size < hose->regions[i].size)
273 				hose->pci_io = hose->regions + i;
274 			break;
275 		case PCI_REGION_MEM:
276 			if (!hose->pci_mem ||
277 			    hose->pci_mem->size < hose->regions[i].size)
278 				hose->pci_mem = hose->regions + i;
279 			break;
280 		case (PCI_REGION_MEM | PCI_REGION_PREFETCH):
281 			if (!hose->pci_prefetch ||
282 			    hose->pci_prefetch->size < hose->regions[i].size)
283 				hose->pci_prefetch = hose->regions + i;
284 			break;
285 		}
286 	}
287 
288 
289 	if (hose->pci_mem) {
290 		pciauto_region_init(hose->pci_mem);
291 
292 		DEBUGF("PCI Autoconfig: Bus Memory region: [%lx-%lx],\n"
293 		       "\t\tPhysical Memory [%x-%x]\n",
294 		    hose->pci_mem->bus_start,
295 		    hose->pci_mem->bus_start + hose->pci_mem->size - 1,
296 		    hose->pci_mem->phys_start,
297 		    hose->pci_mem->phys_start + hose->pci_mem->size - 1);
298 	}
299 
300 	if (hose->pci_prefetch) {
301 		pciauto_region_init(hose->pci_prefetch);
302 
303 		DEBUGF("PCI Autoconfig: Bus Prefetchable Mem: [%lx-%lx],\n"
304 		       "\t\tPhysical Memory [%x-%x]\n",
305 		    hose->pci_prefetch->bus_start,
306 		    hose->pci_prefetch->bus_start + hose->pci_prefetch->size - 1,
307 		    hose->pci_prefetch->phys_start,
308 		    hose->pci_prefetch->phys_start +
309 				hose->pci_prefetch->size - 1);
310 	}
311 
312 	if (hose->pci_io) {
313 		pciauto_region_init(hose->pci_io);
314 
315 		DEBUGF("PCI Autoconfig: Bus I/O region: [%lx-%lx],\n"
316 		       "\t\tPhysical Memory: [%x-%x]\n",
317 		    hose->pci_io->bus_start,
318 		    hose->pci_io->bus_start + hose->pci_io->size - 1,
319 		    hose->pci_io->phys_start,
320 		    hose->pci_io->phys_start + hose->pci_io->size - 1);
321 
322 	}
323 }
324 
325 /* HJF: Changed this to return int. I think this is required
326  * to get the correct result when scanning bridges
327  */
328 int pciauto_config_device(struct pci_controller *hose, pci_dev_t dev)
329 {
330 	unsigned int sub_bus = PCI_BUS(dev);
331 	unsigned short class;
332 	unsigned char prg_iface;
333 	int n;
334 
335 	pci_hose_read_config_word(hose, dev, PCI_CLASS_DEVICE, &class);
336 
337 	switch(class) {
338 	case PCI_CLASS_PROCESSOR_POWERPC: /* an agent or end-point */
339 		DEBUGF("PCI AutoConfig: Found PowerPC device\n");
340 		pciauto_setup_device(hose, dev, 6, hose->pci_mem,
341 				     hose->pci_prefetch, hose->pci_io);
342 		break;
343 
344 	case PCI_CLASS_BRIDGE_PCI:
345 		hose->current_busno++;
346 		pciauto_setup_device(hose, dev, 2, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
347 
348 		DEBUGF("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_DEV(dev));
349 
350 		/* Passing in current_busno allows for sibling P2P bridges */
351 		pciauto_prescan_setup_bridge(hose, dev, hose->current_busno);
352 		/*
353 		 * need to figure out if this is a subordinate bridge on the bus
354 		 * to be able to properly set the pri/sec/sub bridge registers.
355 		 */
356 		n = pci_hose_scan_bus(hose, hose->current_busno);
357 
358 		/* figure out the deepest we've gone for this leg */
359 		sub_bus = max(n, sub_bus);
360 		pciauto_postscan_setup_bridge(hose, dev, sub_bus);
361 
362 		sub_bus = hose->current_busno;
363 		break;
364 
365 	case PCI_CLASS_STORAGE_IDE:
366 		pci_hose_read_config_byte(hose, dev, PCI_CLASS_PROG, &prg_iface);
367 		if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
368 			DEBUGF("PCI Autoconfig: Skipping legacy mode IDE controller\n");
369 			return sub_bus;
370 		}
371 
372 		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
373 		break;
374 
375 	case PCI_CLASS_BRIDGE_CARDBUS:
376 		/* just do a minimal setup of the bridge, let the OS take care of the rest */
377 		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
378 
379 		DEBUGF("PCI Autoconfig: Found P2CardBus bridge, device %d\n", PCI_DEV(dev));
380 
381 		hose->current_busno++;
382 		break;
383 
384 #if defined(CONFIG_PCIAUTO_SKIP_HOST_BRIDGE)
385 	case PCI_CLASS_BRIDGE_OTHER:
386 		DEBUGF("PCI Autoconfig: Skipping bridge device %d\n",
387 		       PCI_DEV(dev));
388 		break;
389 #endif
390 #ifdef CONFIG_MPC834X
391 	case PCI_CLASS_BRIDGE_OTHER:
392 		/*
393 		 * The host/PCI bridge 1 seems broken in 8349 - it presents
394 		 * itself as 'PCI_CLASS_BRIDGE_OTHER' and appears as an _agent_
395 		 * device claiming resources io/mem/irq.. we only allow for
396 		 * the PIMMR window to be allocated (BAR0 - 1MB size)
397 		 */
398 		DEBUGF("PCI Autoconfig: Broken bridge found, only minimal config\n");
399 		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
400 		break;
401 #endif
402 	default:
403 		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
404 		break;
405 	}
406 
407 	return sub_bus;
408 }
409