xref: /openbmc/linux/arch/sparc/kernel/pci_common.c (revision 83a530e1)
1 // SPDX-License-Identifier: GPL-2.0
2 /* pci_common.c: PCI controller common support.
3  *
4  * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
5  */
6 
7 #include <linux/string.h>
8 #include <linux/slab.h>
9 #include <linux/pci.h>
10 #include <linux/device.h>
11 #include <linux/of_device.h>
12 
13 #include <asm/prom.h>
14 #include <asm/oplib.h>
15 
16 #include "pci_impl.h"
17 #include "pci_sun4v.h"
18 
19 static int config_out_of_range(struct pci_pbm_info *pbm,
20 			       unsigned long bus,
21 			       unsigned long devfn,
22 			       unsigned long reg)
23 {
24 	if (bus < pbm->pci_first_busno ||
25 	    bus > pbm->pci_last_busno)
26 		return 1;
27 	return 0;
28 }
29 
30 static void *sun4u_config_mkaddr(struct pci_pbm_info *pbm,
31 				 unsigned long bus,
32 				 unsigned long devfn,
33 				 unsigned long reg)
34 {
35 	unsigned long rbits = pbm->config_space_reg_bits;
36 
37 	if (config_out_of_range(pbm, bus, devfn, reg))
38 		return NULL;
39 
40 	reg = (reg & ((1 << rbits) - 1));
41 	devfn <<= rbits;
42 	bus <<= rbits + 8;
43 
44 	return (void *)	(pbm->config_space | bus | devfn | reg);
45 }
46 
47 /* At least on Sabre, it is necessary to access all PCI host controller
48  * registers at their natural size, otherwise zeros are returned.
49  * Strange but true, and I see no language in the UltraSPARC-IIi
50  * programmer's manual that mentions this even indirectly.
51  */
52 static int sun4u_read_pci_cfg_host(struct pci_pbm_info *pbm,
53 				   unsigned char bus, unsigned int devfn,
54 				   int where, int size, u32 *value)
55 {
56 	u32 tmp32, *addr;
57 	u16 tmp16;
58 	u8 tmp8;
59 
60 	addr = sun4u_config_mkaddr(pbm, bus, devfn, where);
61 	if (!addr)
62 		return PCIBIOS_SUCCESSFUL;
63 
64 	switch (size) {
65 	case 1:
66 		if (where < 8) {
67 			unsigned long align = (unsigned long) addr;
68 
69 			align &= ~1;
70 			pci_config_read16((u16 *)align, &tmp16);
71 			if (where & 1)
72 				*value = tmp16 >> 8;
73 			else
74 				*value = tmp16 & 0xff;
75 		} else {
76 			pci_config_read8((u8 *)addr, &tmp8);
77 			*value = (u32) tmp8;
78 		}
79 		break;
80 
81 	case 2:
82 		if (where < 8) {
83 			pci_config_read16((u16 *)addr, &tmp16);
84 			*value = (u32) tmp16;
85 		} else {
86 			pci_config_read8((u8 *)addr, &tmp8);
87 			*value = (u32) tmp8;
88 			pci_config_read8(((u8 *)addr) + 1, &tmp8);
89 			*value |= ((u32) tmp8) << 8;
90 		}
91 		break;
92 
93 	case 4:
94 		tmp32 = 0xffffffff;
95 		sun4u_read_pci_cfg_host(pbm, bus, devfn,
96 					where, 2, &tmp32);
97 		*value = tmp32;
98 
99 		tmp32 = 0xffffffff;
100 		sun4u_read_pci_cfg_host(pbm, bus, devfn,
101 					where + 2, 2, &tmp32);
102 		*value |= tmp32 << 16;
103 		break;
104 	}
105 	return PCIBIOS_SUCCESSFUL;
106 }
107 
108 static int sun4u_read_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
109 			      int where, int size, u32 *value)
110 {
111 	struct pci_pbm_info *pbm = bus_dev->sysdata;
112 	unsigned char bus = bus_dev->number;
113 	u32 *addr;
114 	u16 tmp16;
115 	u8 tmp8;
116 
117 	switch (size) {
118 	case 1:
119 		*value = 0xff;
120 		break;
121 	case 2:
122 		*value = 0xffff;
123 		break;
124 	case 4:
125 		*value = 0xffffffff;
126 		break;
127 	}
128 
129 	if (!bus_dev->number && !PCI_SLOT(devfn))
130 		return sun4u_read_pci_cfg_host(pbm, bus, devfn, where,
131 					       size, value);
132 
133 	addr = sun4u_config_mkaddr(pbm, bus, devfn, where);
134 	if (!addr)
135 		return PCIBIOS_SUCCESSFUL;
136 
137 	switch (size) {
138 	case 1:
139 		pci_config_read8((u8 *)addr, &tmp8);
140 		*value = (u32) tmp8;
141 		break;
142 
143 	case 2:
144 		if (where & 0x01) {
145 			printk("pci_read_config_word: misaligned reg [%x]\n",
146 			       where);
147 			return PCIBIOS_SUCCESSFUL;
148 		}
149 		pci_config_read16((u16 *)addr, &tmp16);
150 		*value = (u32) tmp16;
151 		break;
152 
153 	case 4:
154 		if (where & 0x03) {
155 			printk("pci_read_config_dword: misaligned reg [%x]\n",
156 			       where);
157 			return PCIBIOS_SUCCESSFUL;
158 		}
159 		pci_config_read32(addr, value);
160 		break;
161 	}
162 	return PCIBIOS_SUCCESSFUL;
163 }
164 
165 static int sun4u_write_pci_cfg_host(struct pci_pbm_info *pbm,
166 				    unsigned char bus, unsigned int devfn,
167 				    int where, int size, u32 value)
168 {
169 	u32 *addr;
170 
171 	addr = sun4u_config_mkaddr(pbm, bus, devfn, where);
172 	if (!addr)
173 		return PCIBIOS_SUCCESSFUL;
174 
175 	switch (size) {
176 	case 1:
177 		if (where < 8) {
178 			unsigned long align = (unsigned long) addr;
179 			u16 tmp16;
180 
181 			align &= ~1;
182 			pci_config_read16((u16 *)align, &tmp16);
183 			if (where & 1) {
184 				tmp16 &= 0x00ff;
185 				tmp16 |= value << 8;
186 			} else {
187 				tmp16 &= 0xff00;
188 				tmp16 |= value;
189 			}
190 			pci_config_write16((u16 *)align, tmp16);
191 		} else
192 			pci_config_write8((u8 *)addr, value);
193 		break;
194 	case 2:
195 		if (where < 8) {
196 			pci_config_write16((u16 *)addr, value);
197 		} else {
198 			pci_config_write8((u8 *)addr, value & 0xff);
199 			pci_config_write8(((u8 *)addr) + 1, value >> 8);
200 		}
201 		break;
202 	case 4:
203 		sun4u_write_pci_cfg_host(pbm, bus, devfn,
204 					 where, 2, value & 0xffff);
205 		sun4u_write_pci_cfg_host(pbm, bus, devfn,
206 					 where + 2, 2, value >> 16);
207 		break;
208 	}
209 	return PCIBIOS_SUCCESSFUL;
210 }
211 
212 static int sun4u_write_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
213 			       int where, int size, u32 value)
214 {
215 	struct pci_pbm_info *pbm = bus_dev->sysdata;
216 	unsigned char bus = bus_dev->number;
217 	u32 *addr;
218 
219 	if (!bus_dev->number && !PCI_SLOT(devfn))
220 		return sun4u_write_pci_cfg_host(pbm, bus, devfn, where,
221 						size, value);
222 
223 	addr = sun4u_config_mkaddr(pbm, bus, devfn, where);
224 	if (!addr)
225 		return PCIBIOS_SUCCESSFUL;
226 
227 	switch (size) {
228 	case 1:
229 		pci_config_write8((u8 *)addr, value);
230 		break;
231 
232 	case 2:
233 		if (where & 0x01) {
234 			printk("pci_write_config_word: misaligned reg [%x]\n",
235 			       where);
236 			return PCIBIOS_SUCCESSFUL;
237 		}
238 		pci_config_write16((u16 *)addr, value);
239 		break;
240 
241 	case 4:
242 		if (where & 0x03) {
243 			printk("pci_write_config_dword: misaligned reg [%x]\n",
244 			       where);
245 			return PCIBIOS_SUCCESSFUL;
246 		}
247 		pci_config_write32(addr, value);
248 	}
249 	return PCIBIOS_SUCCESSFUL;
250 }
251 
252 struct pci_ops sun4u_pci_ops = {
253 	.read =		sun4u_read_pci_cfg,
254 	.write =	sun4u_write_pci_cfg,
255 };
256 
257 static int sun4v_read_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
258 			      int where, int size, u32 *value)
259 {
260 	struct pci_pbm_info *pbm = bus_dev->sysdata;
261 	u32 devhandle = pbm->devhandle;
262 	unsigned int bus = bus_dev->number;
263 	unsigned int device = PCI_SLOT(devfn);
264 	unsigned int func = PCI_FUNC(devfn);
265 	unsigned long ret;
266 
267 	if (config_out_of_range(pbm, bus, devfn, where)) {
268 		ret = ~0UL;
269 	} else {
270 		ret = pci_sun4v_config_get(devhandle,
271 				HV_PCI_DEVICE_BUILD(bus, device, func),
272 				where, size);
273 	}
274 	switch (size) {
275 	case 1:
276 		*value = ret & 0xff;
277 		break;
278 	case 2:
279 		*value = ret & 0xffff;
280 		break;
281 	case 4:
282 		*value = ret & 0xffffffff;
283 		break;
284 	}
285 
286 
287 	return PCIBIOS_SUCCESSFUL;
288 }
289 
290 static int sun4v_write_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
291 			       int where, int size, u32 value)
292 {
293 	struct pci_pbm_info *pbm = bus_dev->sysdata;
294 	u32 devhandle = pbm->devhandle;
295 	unsigned int bus = bus_dev->number;
296 	unsigned int device = PCI_SLOT(devfn);
297 	unsigned int func = PCI_FUNC(devfn);
298 
299 	if (config_out_of_range(pbm, bus, devfn, where)) {
300 		/* Do nothing. */
301 	} else {
302 		/* We don't check for hypervisor errors here, but perhaps
303 		 * we should and influence our return value depending upon
304 		 * what kind of error is thrown.
305 		 */
306 		pci_sun4v_config_put(devhandle,
307 				     HV_PCI_DEVICE_BUILD(bus, device, func),
308 				     where, size, value);
309 	}
310 	return PCIBIOS_SUCCESSFUL;
311 }
312 
313 struct pci_ops sun4v_pci_ops = {
314 	.read =		sun4v_read_pci_cfg,
315 	.write =	sun4v_write_pci_cfg,
316 };
317 
318 void pci_get_pbm_props(struct pci_pbm_info *pbm)
319 {
320 	const u32 *val = of_get_property(pbm->op->dev.of_node, "bus-range", NULL);
321 
322 	pbm->pci_first_busno = val[0];
323 	pbm->pci_last_busno = val[1];
324 
325 	val = of_get_property(pbm->op->dev.of_node, "ino-bitmap", NULL);
326 	if (val) {
327 		pbm->ino_bitmap = (((u64)val[1] << 32UL) |
328 				   ((u64)val[0] <<  0UL));
329 	}
330 }
331 
332 static void pci_register_legacy_regions(struct resource *io_res,
333 					struct resource *mem_res)
334 {
335 	struct resource *p;
336 
337 	/* VGA Video RAM. */
338 	p = kzalloc(sizeof(*p), GFP_KERNEL);
339 	if (!p)
340 		return;
341 
342 	p->name = "Video RAM area";
343 	p->start = mem_res->start + 0xa0000UL;
344 	p->end = p->start + 0x1ffffUL;
345 	p->flags = IORESOURCE_BUSY;
346 	request_resource(mem_res, p);
347 }
348 
349 static void pci_register_iommu_region(struct pci_pbm_info *pbm)
350 {
351 	const u32 *vdma = of_get_property(pbm->op->dev.of_node, "virtual-dma",
352 					  NULL);
353 
354 	if (vdma) {
355 		struct resource *rp = kzalloc(sizeof(*rp), GFP_KERNEL);
356 
357 		if (!rp) {
358 			pr_info("%s: Cannot allocate IOMMU resource.\n",
359 				pbm->name);
360 			return;
361 		}
362 		rp->name = "IOMMU";
363 		rp->start = pbm->mem_space.start + (unsigned long) vdma[0];
364 		rp->end = rp->start + (unsigned long) vdma[1] - 1UL;
365 		rp->flags = IORESOURCE_BUSY;
366 		if (request_resource(&pbm->mem_space, rp)) {
367 			pr_info("%s: Unable to request IOMMU resource.\n",
368 				pbm->name);
369 			kfree(rp);
370 		}
371 	}
372 }
373 
374 void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
375 {
376 	const struct linux_prom_pci_ranges *pbm_ranges;
377 	int i, saw_mem, saw_io;
378 	int num_pbm_ranges;
379 
380 	/* Corresponding generic code in of_pci_get_host_bridge_resources() */
381 
382 	saw_mem = saw_io = 0;
383 	pbm_ranges = of_get_property(pbm->op->dev.of_node, "ranges", &i);
384 	if (!pbm_ranges) {
385 		prom_printf("PCI: Fatal error, missing PBM ranges property "
386 			    " for %s\n",
387 			    pbm->name);
388 		prom_halt();
389 	}
390 
391 	num_pbm_ranges = i / sizeof(*pbm_ranges);
392 	memset(&pbm->mem64_space, 0, sizeof(struct resource));
393 
394 	for (i = 0; i < num_pbm_ranges; i++) {
395 		const struct linux_prom_pci_ranges *pr = &pbm_ranges[i];
396 		unsigned long a, size, region_a;
397 		u32 parent_phys_hi, parent_phys_lo;
398 		u32 child_phys_mid, child_phys_lo;
399 		u32 size_hi, size_lo;
400 		int type;
401 
402 		parent_phys_hi = pr->parent_phys_hi;
403 		parent_phys_lo = pr->parent_phys_lo;
404 		child_phys_mid = pr->child_phys_mid;
405 		child_phys_lo = pr->child_phys_lo;
406 		if (tlb_type == hypervisor)
407 			parent_phys_hi &= 0x0fffffff;
408 
409 		size_hi = pr->size_hi;
410 		size_lo = pr->size_lo;
411 
412 		type = (pr->child_phys_hi >> 24) & 0x3;
413 		a = (((unsigned long)parent_phys_hi << 32UL) |
414 		     ((unsigned long)parent_phys_lo  <<  0UL));
415 		region_a = (((unsigned long)child_phys_mid << 32UL) |
416 		     ((unsigned long)child_phys_lo  <<  0UL));
417 		size = (((unsigned long)size_hi << 32UL) |
418 			((unsigned long)size_lo  <<  0UL));
419 
420 		switch (type) {
421 		case 0:
422 			/* PCI config space, 16MB */
423 			pbm->config_space = a;
424 			break;
425 
426 		case 1:
427 			/* 16-bit IO space, 16MB */
428 			pbm->io_space.start = a;
429 			pbm->io_space.end = a + size - 1UL;
430 			pbm->io_space.flags = IORESOURCE_IO;
431 			pbm->io_offset = a - region_a;
432 			saw_io = 1;
433 			break;
434 
435 		case 2:
436 			/* 32-bit MEM space, 2GB */
437 			pbm->mem_space.start = a;
438 			pbm->mem_space.end = a + size - 1UL;
439 			pbm->mem_space.flags = IORESOURCE_MEM;
440 			pbm->mem_offset = a - region_a;
441 			saw_mem = 1;
442 			break;
443 
444 		case 3:
445 			/* 64-bit MEM handling */
446 			pbm->mem64_space.start = a;
447 			pbm->mem64_space.end = a + size - 1UL;
448 			pbm->mem64_space.flags = IORESOURCE_MEM;
449 			pbm->mem64_offset = a - region_a;
450 			saw_mem = 1;
451 			break;
452 
453 		default:
454 			break;
455 		}
456 	}
457 
458 	if (!saw_io || !saw_mem) {
459 		prom_printf("%s: Fatal error, missing %s PBM range.\n",
460 			    pbm->name,
461 			    (!saw_io ? "IO" : "MEM"));
462 		prom_halt();
463 	}
464 
465 	if (pbm->io_space.flags)
466 		printk("%s: PCI IO %pR offset %llx\n",
467 		       pbm->name, &pbm->io_space, pbm->io_offset);
468 	if (pbm->mem_space.flags)
469 		printk("%s: PCI MEM %pR offset %llx\n",
470 		       pbm->name, &pbm->mem_space, pbm->mem_offset);
471 	if (pbm->mem64_space.flags && pbm->mem_space.flags) {
472 		if (pbm->mem64_space.start <= pbm->mem_space.end)
473 			pbm->mem64_space.start = pbm->mem_space.end + 1;
474 		if (pbm->mem64_space.start > pbm->mem64_space.end)
475 			pbm->mem64_space.flags = 0;
476 	}
477 
478 	if (pbm->mem64_space.flags)
479 		printk("%s: PCI MEM64 %pR offset %llx\n",
480 		       pbm->name, &pbm->mem64_space, pbm->mem64_offset);
481 
482 	pbm->io_space.name = pbm->mem_space.name = pbm->name;
483 	pbm->mem64_space.name = pbm->name;
484 
485 	request_resource(&ioport_resource, &pbm->io_space);
486 	request_resource(&iomem_resource, &pbm->mem_space);
487 	if (pbm->mem64_space.flags)
488 		request_resource(&iomem_resource, &pbm->mem64_space);
489 
490 	pci_register_legacy_regions(&pbm->io_space,
491 				    &pbm->mem_space);
492 	pci_register_iommu_region(pbm);
493 }
494 
495 /* Generic helper routines for PCI error reporting. */
496 void pci_scan_for_target_abort(struct pci_pbm_info *pbm,
497 			       struct pci_bus *pbus)
498 {
499 	struct pci_dev *pdev;
500 	struct pci_bus *bus;
501 
502 	list_for_each_entry(pdev, &pbus->devices, bus_list) {
503 		u16 status, error_bits;
504 
505 		pci_read_config_word(pdev, PCI_STATUS, &status);
506 		error_bits =
507 			(status & (PCI_STATUS_SIG_TARGET_ABORT |
508 				   PCI_STATUS_REC_TARGET_ABORT));
509 		if (error_bits) {
510 			pci_write_config_word(pdev, PCI_STATUS, error_bits);
511 			printk("%s: Device %s saw Target Abort [%016x]\n",
512 			       pbm->name, pci_name(pdev), status);
513 		}
514 	}
515 
516 	list_for_each_entry(bus, &pbus->children, node)
517 		pci_scan_for_target_abort(pbm, bus);
518 }
519 
520 void pci_scan_for_master_abort(struct pci_pbm_info *pbm,
521 			       struct pci_bus *pbus)
522 {
523 	struct pci_dev *pdev;
524 	struct pci_bus *bus;
525 
526 	list_for_each_entry(pdev, &pbus->devices, bus_list) {
527 		u16 status, error_bits;
528 
529 		pci_read_config_word(pdev, PCI_STATUS, &status);
530 		error_bits =
531 			(status & (PCI_STATUS_REC_MASTER_ABORT));
532 		if (error_bits) {
533 			pci_write_config_word(pdev, PCI_STATUS, error_bits);
534 			printk("%s: Device %s received Master Abort [%016x]\n",
535 			       pbm->name, pci_name(pdev), status);
536 		}
537 	}
538 
539 	list_for_each_entry(bus, &pbus->children, node)
540 		pci_scan_for_master_abort(pbm, bus);
541 }
542 
543 void pci_scan_for_parity_error(struct pci_pbm_info *pbm,
544 			       struct pci_bus *pbus)
545 {
546 	struct pci_dev *pdev;
547 	struct pci_bus *bus;
548 
549 	list_for_each_entry(pdev, &pbus->devices, bus_list) {
550 		u16 status, error_bits;
551 
552 		pci_read_config_word(pdev, PCI_STATUS, &status);
553 		error_bits =
554 			(status & (PCI_STATUS_PARITY |
555 				   PCI_STATUS_DETECTED_PARITY));
556 		if (error_bits) {
557 			pci_write_config_word(pdev, PCI_STATUS, error_bits);
558 			printk("%s: Device %s saw Parity Error [%016x]\n",
559 			       pbm->name, pci_name(pdev), status);
560 		}
561 	}
562 
563 	list_for_each_entry(bus, &pbus->children, node)
564 		pci_scan_for_parity_error(pbm, bus);
565 }
566