xref: /openbmc/u-boot/drivers/pci/pci_auto.c (revision 38d299c2)
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 #ifdef CONFIG_PCI
19 
20 #include <pci.h>
21 
22 #undef DEBUG
23 #ifdef DEBUG
24 #define DEBUGF(x...) printf(x)
25 #else
26 #define DEBUGF(x...)
27 #endif /* DEBUG */
28 
29 #define	PCIAUTO_IDE_MODE_MASK		0x05
30 
31 /* the user can define CFG_PCI_CACHE_LINE_SIZE to avoid problems */
32 #ifndef CFG_PCI_CACHE_LINE_SIZE
33 #define CFG_PCI_CACHE_LINE_SIZE	8
34 #endif
35 
36 /*
37  *
38  */
39 
40 void pciauto_region_init(struct pci_region* res)
41 {
42 	/*
43 	 * Avoid allocating PCI resources from address 0 -- this is illegal
44 	 * according to PCI 2.1 and moreover, this is known to cause Linux IDE
45 	 * drivers to fail. Use a reasonable starting value of 0x1000 instead.
46 	 */
47 	res->bus_lower = res->bus_start ? res->bus_start : 0x1000;
48 }
49 
50 void pciauto_region_align(struct pci_region *res, unsigned long size)
51 {
52 	res->bus_lower = ((res->bus_lower - 1) | (size - 1)) + 1;
53 }
54 
55 int pciauto_region_allocate(struct pci_region* res, unsigned int size, unsigned int *bar)
56 {
57 	unsigned long addr;
58 
59 	if (!res) {
60 		DEBUGF("No resource");
61 		goto error;
62 	}
63 
64 	addr = ((res->bus_lower - 1) | (size - 1)) + 1;
65 
66 	if (addr - res->bus_start + size > res->size) {
67 		DEBUGF("No room in resource");
68 		goto error;
69 	}
70 
71 	res->bus_lower = addr + size;
72 
73 	DEBUGF("address=0x%lx bus_lower=%x", addr, res->bus_lower);
74 
75 	*bar = addr;
76 	return 0;
77 
78  error:
79 	*bar = 0xffffffff;
80 	return -1;
81 }
82 
83 /*
84  *
85  */
86 
87 void pciauto_setup_device(struct pci_controller *hose,
88 			  pci_dev_t dev, int bars_num,
89 			  struct pci_region *mem,
90 			  struct pci_region *prefetch,
91 			  struct pci_region *io)
92 {
93 	unsigned int bar_value, bar_response, bar_size;
94 	unsigned int cmdstat = 0;
95 	struct pci_region *bar_res;
96 	int bar, bar_nr = 0;
97 	int found_mem64 = 0;
98 
99 	pci_hose_read_config_dword(hose, dev, PCI_COMMAND, &cmdstat);
100 	cmdstat = (cmdstat & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) | PCI_COMMAND_MASTER;
101 
102 	for (bar = PCI_BASE_ADDRESS_0; bar < PCI_BASE_ADDRESS_0 + (bars_num*4); bar += 4) {
103 		/* Tickle the BAR and get the response */
104 		pci_hose_write_config_dword(hose, dev, bar, 0xffffffff);
105 		pci_hose_read_config_dword(hose, dev, bar, &bar_response);
106 
107 		/* If BAR is not implemented go to the next BAR */
108 		if (!bar_response)
109 			continue;
110 
111 		found_mem64 = 0;
112 
113 		/* Check the BAR type and set our address mask */
114 		if (bar_response & PCI_BASE_ADDRESS_SPACE) {
115 			bar_size = ((~(bar_response & PCI_BASE_ADDRESS_IO_MASK))
116 				   & 0xffff) + 1;
117 			bar_res = io;
118 
119 			DEBUGF("PCI Autoconfig: BAR %d, I/O, size=0x%x, ", bar_nr, bar_size);
120 		} else {
121 			if ( (bar_response & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
122 			     PCI_BASE_ADDRESS_MEM_TYPE_64)
123 				found_mem64 = 1;
124 
125 			bar_size = ~(bar_response & PCI_BASE_ADDRESS_MEM_MASK) + 1;
126 			if (prefetch && (bar_response & PCI_BASE_ADDRESS_MEM_PREFETCH))
127 				bar_res = prefetch;
128 			else
129 				bar_res = mem;
130 
131 			DEBUGF("PCI Autoconfig: BAR %d, Mem, size=0x%x, ", bar_nr, bar_size);
132 		}
133 
134 		if (pciauto_region_allocate(bar_res, bar_size, &bar_value) == 0) {
135 			/* Write it out and update our limit */
136 			pci_hose_write_config_dword(hose, dev, bar, bar_value);
137 
138 			/*
139 			 * If we are a 64-bit decoder then increment to the
140 			 * upper 32 bits of the bar and force it to locate
141 			 * in the lower 4GB of memory.
142 			 */
143 			if (found_mem64) {
144 				bar += 4;
145 				pci_hose_write_config_dword(hose, dev, bar, 0x00000000);
146 			}
147 
148 			cmdstat |= (bar_response & PCI_BASE_ADDRESS_SPACE) ?
149 				PCI_COMMAND_IO : PCI_COMMAND_MEMORY;
150 		}
151 
152 		DEBUGF("\n");
153 
154 		bar_nr++;
155 	}
156 
157 	pci_hose_write_config_dword(hose, dev, PCI_COMMAND, cmdstat);
158 	pci_hose_write_config_byte(hose, dev, PCI_CACHE_LINE_SIZE,
159 		CFG_PCI_CACHE_LINE_SIZE);
160 	pci_hose_write_config_byte(hose, dev, PCI_LATENCY_TIMER, 0x80);
161 }
162 
163 void pciauto_prescan_setup_bridge(struct pci_controller *hose,
164 					 pci_dev_t dev, int sub_bus)
165 {
166 	struct pci_region *pci_mem = hose->pci_mem;
167 	struct pci_region *pci_prefetch = hose->pci_prefetch;
168 	struct pci_region *pci_io = hose->pci_io;
169 	unsigned int cmdstat;
170 
171 	pci_hose_read_config_dword(hose, dev, PCI_COMMAND, &cmdstat);
172 
173 	/* Configure bus number registers */
174 	pci_hose_write_config_byte(hose, dev, PCI_PRIMARY_BUS,
175 				   PCI_BUS(dev) - hose->first_busno);
176 	pci_hose_write_config_byte(hose, dev, PCI_SECONDARY_BUS,
177 				   sub_bus - hose->first_busno);
178 	pci_hose_write_config_byte(hose, dev, PCI_SUBORDINATE_BUS, 0xff);
179 
180 	if (pci_mem) {
181 		/* Round memory allocator to 1MB boundary */
182 		pciauto_region_align(pci_mem, 0x100000);
183 
184 		/* Set up memory and I/O filter limits, assume 32-bit I/O space */
185 		pci_hose_write_config_word(hose, dev, PCI_MEMORY_BASE,
186 					(pci_mem->bus_lower & 0xfff00000) >> 16);
187 
188 		cmdstat |= PCI_COMMAND_MEMORY;
189 	}
190 
191 	if (pci_prefetch) {
192 		/* Round memory allocator to 1MB boundary */
193 		pciauto_region_align(pci_prefetch, 0x100000);
194 
195 		/* Set up memory and I/O filter limits, assume 32-bit I/O space */
196 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
197 					(pci_prefetch->bus_lower & 0xfff00000) >> 16);
198 
199 		cmdstat |= PCI_COMMAND_MEMORY;
200 	} else {
201 		/* We don't support prefetchable memory for now, so disable */
202 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE, 0x1000);
203 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT, 0x0);
204 	}
205 
206 	if (pci_io) {
207 		/* Round I/O allocator to 4KB boundary */
208 		pciauto_region_align(pci_io, 0x1000);
209 
210 		pci_hose_write_config_byte(hose, dev, PCI_IO_BASE,
211 					(pci_io->bus_lower & 0x0000f000) >> 8);
212 		pci_hose_write_config_word(hose, dev, PCI_IO_BASE_UPPER16,
213 					(pci_io->bus_lower & 0xffff0000) >> 16);
214 
215 		cmdstat |= PCI_COMMAND_IO;
216 	}
217 
218 	/* Enable memory and I/O accesses, enable bus master */
219 	pci_hose_write_config_dword(hose, dev, PCI_COMMAND, cmdstat | PCI_COMMAND_MASTER);
220 }
221 
222 void pciauto_postscan_setup_bridge(struct pci_controller *hose,
223 					  pci_dev_t dev, int sub_bus)
224 {
225 	struct pci_region *pci_mem = hose->pci_mem;
226 	struct pci_region *pci_prefetch = hose->pci_prefetch;
227 	struct pci_region *pci_io = hose->pci_io;
228 
229 	/* Configure bus number registers */
230 	pci_hose_write_config_byte(hose, dev, PCI_SUBORDINATE_BUS,
231 				   sub_bus - hose->first_busno);
232 
233 	if (pci_mem) {
234 		/* Round memory allocator to 1MB boundary */
235 		pciauto_region_align(pci_mem, 0x100000);
236 
237 		pci_hose_write_config_word(hose, dev, PCI_MEMORY_LIMIT,
238 					(pci_mem->bus_lower-1) >> 16);
239 	}
240 
241 	if (pci_prefetch) {
242 		/* Round memory allocator to 1MB boundary */
243 		pciauto_region_align(pci_prefetch, 0x100000);
244 
245 		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT,
246 					(pci_prefetch->bus_lower-1) >> 16);
247 	}
248 
249 	if (pci_io) {
250 		/* Round I/O allocator to 4KB boundary */
251 		pciauto_region_align(pci_io, 0x1000);
252 
253 		pci_hose_write_config_byte(hose, dev, PCI_IO_LIMIT,
254 					((pci_io->bus_lower-1) & 0x0000f000) >> 8);
255 		pci_hose_write_config_word(hose, dev, PCI_IO_LIMIT_UPPER16,
256 					((pci_io->bus_lower-1) & 0xffff0000) >> 16);
257 	}
258 }
259 
260 /*
261  *
262  */
263 
264 void pciauto_config_init(struct pci_controller *hose)
265 {
266 	int i;
267 
268 	hose->pci_io = hose->pci_mem = NULL;
269 
270 	for (i=0; i<hose->region_count; i++) {
271 		switch(hose->regions[i].flags) {
272 		case PCI_REGION_IO:
273 			if (!hose->pci_io ||
274 			    hose->pci_io->size < hose->regions[i].size)
275 				hose->pci_io = hose->regions + i;
276 			break;
277 		case PCI_REGION_MEM:
278 			if (!hose->pci_mem ||
279 			    hose->pci_mem->size < hose->regions[i].size)
280 				hose->pci_mem = hose->regions + i;
281 			break;
282 		case (PCI_REGION_MEM | PCI_REGION_PREFETCH):
283 			if (!hose->pci_prefetch ||
284 			    hose->pci_prefetch->size < hose->regions[i].size)
285 				hose->pci_prefetch = hose->regions + i;
286 			break;
287 		}
288 	}
289 
290 
291 	if (hose->pci_mem) {
292 		pciauto_region_init(hose->pci_mem);
293 
294 		DEBUGF("PCI Autoconfig: Bus Memory region: [%lx-%lx],\n"
295 		       "\t\tPhysical Memory [%x-%x]\n",
296 		    hose->pci_mem->bus_start,
297 		    hose->pci_mem->bus_start + hose->pci_mem->size - 1,
298 		    hose->pci_mem->phys_start,
299 		    hose->pci_mem->phys_start + hose->pci_mem->size - 1);
300 	}
301 
302 	if (hose->pci_prefetch) {
303 		pciauto_region_init(hose->pci_prefetch);
304 
305 		DEBUGF("PCI Autoconfig: Bus Prefetchable Mem: [%lx-%lx],\n"
306 		       "\t\tPhysical Memory [%x-%x]\n",
307 		    hose->pci_prefetch->bus_start,
308 		    hose->pci_prefetch->bus_start + hose->pci_prefetch->size - 1,
309 		    hose->pci_prefetch->phys_start,
310 		    hose->pci_prefetch->phys_start +
311 				hose->pci_prefetch->size - 1);
312 	}
313 
314 	if (hose->pci_io) {
315 		pciauto_region_init(hose->pci_io);
316 
317 		DEBUGF("PCI Autoconfig: Bus I/O region: [%lx-%lx],\n"
318 		       "\t\tPhysical Memory: [%x-%x]\n",
319 		    hose->pci_io->bus_start,
320 		    hose->pci_io->bus_start + hose->pci_io->size - 1,
321 		    hose->pci_io->phys_start,
322 		    hose->pci_io->phys_start + hose->pci_io->size - 1);
323 
324 	}
325 }
326 
327 /* HJF: Changed this to return int. I think this is required
328  * to get the correct result when scanning bridges
329  */
330 int pciauto_config_device(struct pci_controller *hose, pci_dev_t dev)
331 {
332 	unsigned int sub_bus = PCI_BUS(dev);
333 	unsigned short class;
334 	unsigned char prg_iface;
335 	int n;
336 
337 	pci_hose_read_config_word(hose, dev, PCI_CLASS_DEVICE, &class);
338 
339 	switch(class) {
340 	case PCI_CLASS_PROCESSOR_POWERPC: /* an agent or end-point */
341 		DEBUGF("PCI AutoConfig: Found PowerPC device\n");
342 		pciauto_setup_device(hose, dev, 6, hose->pci_mem,
343 				     hose->pci_prefetch, hose->pci_io);
344 		break;
345 
346 	case PCI_CLASS_BRIDGE_PCI:
347 		hose->current_busno++;
348 		pciauto_setup_device(hose, dev, 2, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
349 
350 		DEBUGF("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_DEV(dev));
351 
352 		/* Passing in current_busno allows for sibling P2P bridges */
353 		pciauto_prescan_setup_bridge(hose, dev, hose->current_busno);
354 		/*
355 		 * need to figure out if this is a subordinate bridge on the bus
356 		 * to be able to properly set the pri/sec/sub bridge registers.
357 		 */
358 		n = pci_hose_scan_bus(hose, hose->current_busno);
359 
360 		/* figure out the deepest we've gone for this leg */
361 		sub_bus = max(n, sub_bus);
362 		pciauto_postscan_setup_bridge(hose, dev, sub_bus);
363 
364 		sub_bus = hose->current_busno;
365 		break;
366 
367 	case PCI_CLASS_STORAGE_IDE:
368 		pci_hose_read_config_byte(hose, dev, PCI_CLASS_PROG, &prg_iface);
369 		if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
370 			DEBUGF("PCI Autoconfig: Skipping legacy mode IDE controller\n");
371 			return sub_bus;
372 		}
373 
374 		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
375 		break;
376 
377 	case PCI_CLASS_BRIDGE_CARDBUS:
378 		/* just do a minimal setup of the bridge, let the OS take care of the rest */
379 		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
380 
381 		DEBUGF("PCI Autoconfig: Found P2CardBus bridge, device %d\n", PCI_DEV(dev));
382 
383 		hose->current_busno++;
384 		break;
385 
386 #ifdef CONFIG_MPC5200
387 	case PCI_CLASS_BRIDGE_OTHER:
388 		DEBUGF("PCI Autoconfig: Skipping bridge device %d\n",
389 		       PCI_DEV(dev));
390 		break;
391 #endif
392 #ifdef CONFIG_MPC834X
393 	case PCI_CLASS_BRIDGE_OTHER:
394 		/*
395 		 * The host/PCI bridge 1 seems broken in 8349 - it presents
396 		 * itself as 'PCI_CLASS_BRIDGE_OTHER' and appears as an _agent_
397 		 * device claiming resources io/mem/irq.. we only allow for
398 		 * the PIMMR window to be allocated (BAR0 - 1MB size)
399 		 */
400 		DEBUGF("PCI Autoconfig: Broken bridge found, only minimal config\n");
401 		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
402 		break;
403 #endif
404 	default:
405 		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
406 		break;
407 	}
408 
409 	return sub_bus;
410 }
411 
412 #endif /* CONFIG_PCI */
413