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
20static 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
31static 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 */
53static 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
109static 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
166static 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
213static 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
253struct pci_ops sun4u_pci_ops = {
254	.read =		sun4u_read_pci_cfg,
255	.write =	sun4u_write_pci_cfg,
256};
257
258static 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
291static 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
314struct pci_ops sun4v_pci_ops = {
315	.read =		sun4v_read_pci_cfg,
316	.write =	sun4v_write_pci_cfg,
317};
318
319void 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
333static 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
358void 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. */
478void 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
502void 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
525void 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