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