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v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Support routines for initializing a PCI subsystem
  4 *
  5 * Extruded from code written by
  6 *      Dave Rusling (david.rusling@reo.mts.dec.com)
  7 *      David Mosberger (davidm@cs.arizona.edu)
  8 *	David Miller (davem@redhat.com)
  9 *
 10 * Fixed for multiple PCI buses, 1999 Andrea Arcangeli <andrea@suse.de>
 11 *
 
 
 
 
 12 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 13 *	     Resource sorting
 14 */
 15
 16#include <linux/kernel.h>
 17#include <linux/export.h>
 18#include <linux/pci.h>
 19#include <linux/errno.h>
 20#include <linux/ioport.h>
 21#include <linux/cache.h>
 22#include <linux/slab.h>
 23#include "pci.h"
 24
 25static void pci_std_update_resource(struct pci_dev *dev, int resno)
 26{
 27	struct pci_bus_region region;
 28	bool disable;
 29	u16 cmd;
 30	u32 new, check, mask;
 31	int reg;
 32	struct resource *res = dev->resource + resno;
 33
 34	/* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
 35	if (dev->is_virtfn)
 36		return;
 37
 38	/*
 39	 * Ignore resources for unimplemented BARs and unused resource slots
 40	 * for 64 bit BARs.
 41	 */
 42	if (!res->flags)
 43		return;
 44
 45	if (res->flags & IORESOURCE_UNSET)
 46		return;
 47
 48	/*
 49	 * Ignore non-moveable resources.  This might be legacy resources for
 50	 * which no functional BAR register exists or another important
 51	 * system resource we shouldn't move around.
 52	 */
 53	if (res->flags & IORESOURCE_PCI_FIXED)
 54		return;
 55
 56	pcibios_resource_to_bus(dev->bus, &region, res);
 57	new = region.start;
 58
 59	if (res->flags & IORESOURCE_IO) {
 60		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
 61		new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
 62	} else if (resno == PCI_ROM_RESOURCE) {
 63		mask = PCI_ROM_ADDRESS_MASK;
 64	} else {
 65		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 66		new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
 67	}
 68
 69	if (resno < PCI_ROM_RESOURCE) {
 70		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
 71	} else if (resno == PCI_ROM_RESOURCE) {
 72
 73		/*
 74		 * Apparently some Matrox devices have ROM BARs that read
 75		 * as zero when disabled, so don't update ROM BARs unless
 76		 * they're enabled.  See
 77		 * https://lore.kernel.org/r/43147B3D.1030309@vc.cvut.cz/
 78		 */
 79		if (!(res->flags & IORESOURCE_ROM_ENABLE))
 80			return;
 81
 82		reg = dev->rom_base_reg;
 83		new |= PCI_ROM_ADDRESS_ENABLE;
 84	} else
 85		return;
 86
 87	/*
 88	 * We can't update a 64-bit BAR atomically, so when possible,
 89	 * disable decoding so that a half-updated BAR won't conflict
 90	 * with another device.
 91	 */
 92	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
 93	if (disable) {
 94		pci_read_config_word(dev, PCI_COMMAND, &cmd);
 95		pci_write_config_word(dev, PCI_COMMAND,
 96				      cmd & ~PCI_COMMAND_MEMORY);
 97	}
 98
 99	pci_write_config_dword(dev, reg, new);
100	pci_read_config_dword(dev, reg, &check);
101
102	if ((new ^ check) & mask) {
103		pci_err(dev, "BAR %d: error updating (%#08x != %#08x)\n",
104			resno, new, check);
105	}
106
107	if (res->flags & IORESOURCE_MEM_64) {
108		new = region.start >> 16 >> 16;
109		pci_write_config_dword(dev, reg + 4, new);
110		pci_read_config_dword(dev, reg + 4, &check);
111		if (check != new) {
112			pci_err(dev, "BAR %d: error updating (high %#08x != %#08x)\n",
113				resno, new, check);
114		}
115	}
116
117	if (disable)
118		pci_write_config_word(dev, PCI_COMMAND, cmd);
119}
120
121void pci_update_resource(struct pci_dev *dev, int resno)
122{
123	if (resno <= PCI_ROM_RESOURCE)
124		pci_std_update_resource(dev, resno);
125#ifdef CONFIG_PCI_IOV
126	else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
127		pci_iov_update_resource(dev, resno);
128#endif
129}
130
131int pci_claim_resource(struct pci_dev *dev, int resource)
132{
133	struct resource *res = &dev->resource[resource];
134	struct resource *root, *conflict;
135
136	if (res->flags & IORESOURCE_UNSET) {
137		pci_info(dev, "can't claim BAR %d %pR: no address assigned\n",
138			 resource, res);
139		return -EINVAL;
140	}
141
142	/*
143	 * If we have a shadow copy in RAM, the PCI device doesn't respond
144	 * to the shadow range, so we don't need to claim it, and upstream
145	 * bridges don't need to route the range to the device.
146	 */
147	if (res->flags & IORESOURCE_ROM_SHADOW)
148		return 0;
149
150	root = pci_find_parent_resource(dev, res);
151	if (!root) {
152		pci_info(dev, "can't claim BAR %d %pR: no compatible bridge window\n",
153			 resource, res);
154		res->flags |= IORESOURCE_UNSET;
155		return -EINVAL;
156	}
157
158	conflict = request_resource_conflict(root, res);
159	if (conflict) {
160		pci_info(dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
161			 resource, res, conflict->name, conflict);
162		res->flags |= IORESOURCE_UNSET;
163		return -EBUSY;
164	}
165
166	return 0;
167}
168EXPORT_SYMBOL(pci_claim_resource);
169
170void pci_disable_bridge_window(struct pci_dev *dev)
171{
 
 
172	/* MMIO Base/Limit */
173	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
174
175	/* Prefetchable MMIO Base/Limit */
176	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
177	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
178	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
179}
180
181/*
182 * Generic function that returns a value indicating that the device's
183 * original BIOS BAR address was not saved and so is not available for
184 * reinstatement.
185 *
186 * Can be over-ridden by architecture specific code that implements
187 * reinstatement functionality rather than leaving it disabled when
188 * normal allocation attempts fail.
189 */
190resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
191{
192	return 0;
193}
194
195static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
196		int resno, resource_size_t size)
197{
198	struct resource *root, *conflict;
199	resource_size_t fw_addr, start, end;
200
201	fw_addr = pcibios_retrieve_fw_addr(dev, resno);
202	if (!fw_addr)
203		return -ENOMEM;
204
205	start = res->start;
206	end = res->end;
207	res->start = fw_addr;
208	res->end = res->start + size - 1;
209	res->flags &= ~IORESOURCE_UNSET;
210
211	root = pci_find_parent_resource(dev, res);
212	if (!root) {
213		if (res->flags & IORESOURCE_IO)
214			root = &ioport_resource;
215		else
216			root = &iomem_resource;
217	}
218
219	pci_info(dev, "BAR %d: trying firmware assignment %pR\n",
220		 resno, res);
221	conflict = request_resource_conflict(root, res);
222	if (conflict) {
223		pci_info(dev, "BAR %d: %pR conflicts with %s %pR\n",
224			 resno, res, conflict->name, conflict);
225		res->start = start;
226		res->end = end;
227		res->flags |= IORESOURCE_UNSET;
228		return -EBUSY;
229	}
230	return 0;
231}
232
233/*
234 * We don't have to worry about legacy ISA devices, so nothing to do here.
235 * This is marked as __weak because multiple architectures define it; it should
236 * eventually go away.
237 */
238resource_size_t __weak pcibios_align_resource(void *data,
239					      const struct resource *res,
240					      resource_size_t size,
241					      resource_size_t align)
242{
243       return res->start;
244}
245
246static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
247		int resno, resource_size_t size, resource_size_t align)
248{
249	struct resource *res = dev->resource + resno;
250	resource_size_t min;
251	int ret;
252
253	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
254
255	/*
256	 * First, try exact prefetching match.  Even if a 64-bit
257	 * prefetchable bridge window is below 4GB, we can't put a 32-bit
258	 * prefetchable resource in it because pbus_size_mem() assumes a
259	 * 64-bit window will contain no 32-bit resources.  If we assign
260	 * things differently than they were sized, not everything will fit.
261	 */
262	ret = pci_bus_alloc_resource(bus, res, size, align, min,
263				     IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
264				     pcibios_align_resource, dev);
265	if (ret == 0)
266		return 0;
267
268	/*
269	 * If the prefetchable window is only 32 bits wide, we can put
270	 * 64-bit prefetchable resources in it.
271	 */
272	if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
273	     (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
274		ret = pci_bus_alloc_resource(bus, res, size, align, min,
275					     IORESOURCE_PREFETCH,
276					     pcibios_align_resource, dev);
277		if (ret == 0)
278			return 0;
279	}
280
281	/*
282	 * If we didn't find a better match, we can put any memory resource
283	 * in a non-prefetchable window.  If this resource is 32 bits and
284	 * non-prefetchable, the first call already tried the only possibility
285	 * so we don't need to try again.
286	 */
287	if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
288		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
289					     pcibios_align_resource, dev);
290
291	return ret;
292}
293
294static int _pci_assign_resource(struct pci_dev *dev, int resno,
295				resource_size_t size, resource_size_t min_align)
296{
297	struct pci_bus *bus;
298	int ret;
299
300	bus = dev->bus;
301	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
302		if (!bus->parent || !bus->self->transparent)
303			break;
304		bus = bus->parent;
305	}
306
307	return ret;
308}
309
310int pci_assign_resource(struct pci_dev *dev, int resno)
311{
312	struct resource *res = dev->resource + resno;
313	resource_size_t align, size;
314	int ret;
315
316	if (res->flags & IORESOURCE_PCI_FIXED)
317		return 0;
318
319	res->flags |= IORESOURCE_UNSET;
320	align = pci_resource_alignment(dev, res);
321	if (!align) {
322		pci_info(dev, "BAR %d: can't assign %pR (bogus alignment)\n",
323			 resno, res);
324		return -EINVAL;
325	}
326
327	size = resource_size(res);
328	ret = _pci_assign_resource(dev, resno, size, align);
329
330	/*
331	 * If we failed to assign anything, let's try the address
332	 * where firmware left it.  That at least has a chance of
333	 * working, which is better than just leaving it disabled.
334	 */
335	if (ret < 0) {
336		pci_info(dev, "BAR %d: no space for %pR\n", resno, res);
337		ret = pci_revert_fw_address(res, dev, resno, size);
338	}
339
340	if (ret < 0) {
341		pci_info(dev, "BAR %d: failed to assign %pR\n", resno, res);
 
342		return ret;
343	}
344
345	res->flags &= ~IORESOURCE_UNSET;
346	res->flags &= ~IORESOURCE_STARTALIGN;
347	pci_info(dev, "BAR %d: assigned %pR\n", resno, res);
348	if (resno < PCI_BRIDGE_RESOURCES)
349		pci_update_resource(dev, resno);
350
351	return 0;
352}
353EXPORT_SYMBOL(pci_assign_resource);
354
355int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
356			resource_size_t min_align)
357{
358	struct resource *res = dev->resource + resno;
359	unsigned long flags;
360	resource_size_t new_size;
361	int ret;
362
363	if (res->flags & IORESOURCE_PCI_FIXED)
364		return 0;
365
366	flags = res->flags;
367	res->flags |= IORESOURCE_UNSET;
368	if (!res->parent) {
369		pci_info(dev, "BAR %d: can't reassign an unassigned resource %pR\n",
370			 resno, res);
371		return -EINVAL;
372	}
373
374	/* already aligned with min_align */
375	new_size = resource_size(res) + addsize;
376	ret = _pci_assign_resource(dev, resno, new_size, min_align);
377	if (ret) {
378		res->flags = flags;
379		pci_info(dev, "BAR %d: %pR (failed to expand by %#llx)\n",
380			 resno, res, (unsigned long long) addsize);
381		return ret;
382	}
383
384	res->flags &= ~IORESOURCE_UNSET;
385	res->flags &= ~IORESOURCE_STARTALIGN;
386	pci_info(dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
387		 resno, res, (unsigned long long) addsize);
388	if (resno < PCI_BRIDGE_RESOURCES)
389		pci_update_resource(dev, resno);
390
391	return 0;
392}
393
394void pci_release_resource(struct pci_dev *dev, int resno)
395{
396	struct resource *res = dev->resource + resno;
397
398	pci_info(dev, "BAR %d: releasing %pR\n", resno, res);
399
400	if (!res->parent)
401		return;
402
403	release_resource(res);
404	res->end = resource_size(res) - 1;
405	res->start = 0;
406	res->flags |= IORESOURCE_UNSET;
407}
408EXPORT_SYMBOL(pci_release_resource);
409
410int pci_resize_resource(struct pci_dev *dev, int resno, int size)
411{
412	struct resource *res = dev->resource + resno;
413	int old, ret;
414	u32 sizes;
415	u16 cmd;
416
417	/* Make sure the resource isn't assigned before resizing it. */
418	if (!(res->flags & IORESOURCE_UNSET))
419		return -EBUSY;
420
421	pci_read_config_word(dev, PCI_COMMAND, &cmd);
422	if (cmd & PCI_COMMAND_MEMORY)
423		return -EBUSY;
424
425	sizes = pci_rebar_get_possible_sizes(dev, resno);
426	if (!sizes)
427		return -ENOTSUPP;
428
429	if (!(sizes & BIT(size)))
430		return -EINVAL;
431
432	old = pci_rebar_get_current_size(dev, resno);
433	if (old < 0)
434		return old;
435
436	ret = pci_rebar_set_size(dev, resno, size);
437	if (ret)
438		return ret;
439
440	res->end = res->start + pci_rebar_size_to_bytes(size) - 1;
441
442	/* Check if the new config works by trying to assign everything. */
443	if (dev->bus->self) {
444		ret = pci_reassign_bridge_resources(dev->bus->self, res->flags);
445		if (ret)
446			goto error_resize;
447	}
448	return 0;
449
450error_resize:
451	pci_rebar_set_size(dev, resno, old);
452	res->end = res->start + pci_rebar_size_to_bytes(old) - 1;
453	return ret;
454}
455EXPORT_SYMBOL(pci_resize_resource);
456
457int pci_enable_resources(struct pci_dev *dev, int mask)
458{
459	u16 cmd, old_cmd;
460	int i;
461	struct resource *r;
462
463	pci_read_config_word(dev, PCI_COMMAND, &cmd);
464	old_cmd = cmd;
465
466	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
467		if (!(mask & (1 << i)))
468			continue;
469
470		r = &dev->resource[i];
471
472		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
473			continue;
474		if ((i == PCI_ROM_RESOURCE) &&
475				(!(r->flags & IORESOURCE_ROM_ENABLE)))
476			continue;
477
478		if (r->flags & IORESOURCE_UNSET) {
479			pci_err(dev, "can't enable device: BAR %d %pR not assigned\n",
480				i, r);
481			return -EINVAL;
482		}
483
484		if (!r->parent) {
485			pci_err(dev, "can't enable device: BAR %d %pR not claimed\n",
486				i, r);
487			return -EINVAL;
488		}
489
490		if (r->flags & IORESOURCE_IO)
491			cmd |= PCI_COMMAND_IO;
492		if (r->flags & IORESOURCE_MEM)
493			cmd |= PCI_COMMAND_MEMORY;
494	}
495
496	if (cmd != old_cmd) {
497		pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
 
498		pci_write_config_word(dev, PCI_COMMAND, cmd);
499	}
500	return 0;
501}
v4.10.11
 
  1/*
  2 *	drivers/pci/setup-res.c
  3 *
  4 * Extruded from code written by
  5 *      Dave Rusling (david.rusling@reo.mts.dec.com)
  6 *      David Mosberger (davidm@cs.arizona.edu)
  7 *	David Miller (davem@redhat.com)
  8 *
  9 * Support routines for initializing a PCI subsystem.
 10 */
 11
 12/* fixed for multiple pci buses, 1999 Andrea Arcangeli <andrea@suse.de> */
 13
 14/*
 15 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 16 *	     Resource sorting
 17 */
 18
 19#include <linux/kernel.h>
 20#include <linux/export.h>
 21#include <linux/pci.h>
 22#include <linux/errno.h>
 23#include <linux/ioport.h>
 24#include <linux/cache.h>
 25#include <linux/slab.h>
 26#include "pci.h"
 27
 28static void pci_std_update_resource(struct pci_dev *dev, int resno)
 29{
 30	struct pci_bus_region region;
 31	bool disable;
 32	u16 cmd;
 33	u32 new, check, mask;
 34	int reg;
 35	struct resource *res = dev->resource + resno;
 36
 37	/* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
 38	if (dev->is_virtfn)
 39		return;
 40
 41	/*
 42	 * Ignore resources for unimplemented BARs and unused resource slots
 43	 * for 64 bit BARs.
 44	 */
 45	if (!res->flags)
 46		return;
 47
 48	if (res->flags & IORESOURCE_UNSET)
 49		return;
 50
 51	/*
 52	 * Ignore non-moveable resources.  This might be legacy resources for
 53	 * which no functional BAR register exists or another important
 54	 * system resource we shouldn't move around.
 55	 */
 56	if (res->flags & IORESOURCE_PCI_FIXED)
 57		return;
 58
 59	pcibios_resource_to_bus(dev->bus, &region, res);
 60	new = region.start;
 61
 62	if (res->flags & IORESOURCE_IO) {
 63		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
 64		new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
 65	} else if (resno == PCI_ROM_RESOURCE) {
 66		mask = (u32)PCI_ROM_ADDRESS_MASK;
 67	} else {
 68		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 69		new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
 70	}
 71
 72	if (resno < PCI_ROM_RESOURCE) {
 73		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
 74	} else if (resno == PCI_ROM_RESOURCE) {
 75
 76		/*
 77		 * Apparently some Matrox devices have ROM BARs that read
 78		 * as zero when disabled, so don't update ROM BARs unless
 79		 * they're enabled.  See https://lkml.org/lkml/2005/8/30/138.
 
 80		 */
 81		if (!(res->flags & IORESOURCE_ROM_ENABLE))
 82			return;
 83
 84		reg = dev->rom_base_reg;
 85		new |= PCI_ROM_ADDRESS_ENABLE;
 86	} else
 87		return;
 88
 89	/*
 90	 * We can't update a 64-bit BAR atomically, so when possible,
 91	 * disable decoding so that a half-updated BAR won't conflict
 92	 * with another device.
 93	 */
 94	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
 95	if (disable) {
 96		pci_read_config_word(dev, PCI_COMMAND, &cmd);
 97		pci_write_config_word(dev, PCI_COMMAND,
 98				      cmd & ~PCI_COMMAND_MEMORY);
 99	}
100
101	pci_write_config_dword(dev, reg, new);
102	pci_read_config_dword(dev, reg, &check);
103
104	if ((new ^ check) & mask) {
105		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
106			resno, new, check);
107	}
108
109	if (res->flags & IORESOURCE_MEM_64) {
110		new = region.start >> 16 >> 16;
111		pci_write_config_dword(dev, reg + 4, new);
112		pci_read_config_dword(dev, reg + 4, &check);
113		if (check != new) {
114			dev_err(&dev->dev, "BAR %d: error updating (high %#08x != %#08x)\n",
115				resno, new, check);
116		}
117	}
118
119	if (disable)
120		pci_write_config_word(dev, PCI_COMMAND, cmd);
121}
122
123void pci_update_resource(struct pci_dev *dev, int resno)
124{
125	if (resno <= PCI_ROM_RESOURCE)
126		pci_std_update_resource(dev, resno);
127#ifdef CONFIG_PCI_IOV
128	else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
129		pci_iov_update_resource(dev, resno);
130#endif
131}
132
133int pci_claim_resource(struct pci_dev *dev, int resource)
134{
135	struct resource *res = &dev->resource[resource];
136	struct resource *root, *conflict;
137
138	if (res->flags & IORESOURCE_UNSET) {
139		dev_info(&dev->dev, "can't claim BAR %d %pR: no address assigned\n",
140			 resource, res);
141		return -EINVAL;
142	}
143
144	/*
145	 * If we have a shadow copy in RAM, the PCI device doesn't respond
146	 * to the shadow range, so we don't need to claim it, and upstream
147	 * bridges don't need to route the range to the device.
148	 */
149	if (res->flags & IORESOURCE_ROM_SHADOW)
150		return 0;
151
152	root = pci_find_parent_resource(dev, res);
153	if (!root) {
154		dev_info(&dev->dev, "can't claim BAR %d %pR: no compatible bridge window\n",
155			 resource, res);
156		res->flags |= IORESOURCE_UNSET;
157		return -EINVAL;
158	}
159
160	conflict = request_resource_conflict(root, res);
161	if (conflict) {
162		dev_info(&dev->dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
163			 resource, res, conflict->name, conflict);
164		res->flags |= IORESOURCE_UNSET;
165		return -EBUSY;
166	}
167
168	return 0;
169}
170EXPORT_SYMBOL(pci_claim_resource);
171
172void pci_disable_bridge_window(struct pci_dev *dev)
173{
174	dev_info(&dev->dev, "disabling bridge mem windows\n");
175
176	/* MMIO Base/Limit */
177	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
178
179	/* Prefetchable MMIO Base/Limit */
180	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
181	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
182	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
183}
184
185/*
186 * Generic function that returns a value indicating that the device's
187 * original BIOS BAR address was not saved and so is not available for
188 * reinstatement.
189 *
190 * Can be over-ridden by architecture specific code that implements
191 * reinstatement functionality rather than leaving it disabled when
192 * normal allocation attempts fail.
193 */
194resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
195{
196	return 0;
197}
198
199static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
200		int resno, resource_size_t size)
201{
202	struct resource *root, *conflict;
203	resource_size_t fw_addr, start, end;
204
205	fw_addr = pcibios_retrieve_fw_addr(dev, resno);
206	if (!fw_addr)
207		return -ENOMEM;
208
209	start = res->start;
210	end = res->end;
211	res->start = fw_addr;
212	res->end = res->start + size - 1;
213	res->flags &= ~IORESOURCE_UNSET;
214
215	root = pci_find_parent_resource(dev, res);
216	if (!root) {
217		if (res->flags & IORESOURCE_IO)
218			root = &ioport_resource;
219		else
220			root = &iomem_resource;
221	}
222
223	dev_info(&dev->dev, "BAR %d: trying firmware assignment %pR\n",
224		 resno, res);
225	conflict = request_resource_conflict(root, res);
226	if (conflict) {
227		dev_info(&dev->dev, "BAR %d: %pR conflicts with %s %pR\n",
228			 resno, res, conflict->name, conflict);
229		res->start = start;
230		res->end = end;
231		res->flags |= IORESOURCE_UNSET;
232		return -EBUSY;
233	}
234	return 0;
235}
236
 
 
 
 
 
 
 
 
 
 
 
 
 
237static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
238		int resno, resource_size_t size, resource_size_t align)
239{
240	struct resource *res = dev->resource + resno;
241	resource_size_t min;
242	int ret;
243
244	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
245
246	/*
247	 * First, try exact prefetching match.  Even if a 64-bit
248	 * prefetchable bridge window is below 4GB, we can't put a 32-bit
249	 * prefetchable resource in it because pbus_size_mem() assumes a
250	 * 64-bit window will contain no 32-bit resources.  If we assign
251	 * things differently than they were sized, not everything will fit.
252	 */
253	ret = pci_bus_alloc_resource(bus, res, size, align, min,
254				     IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
255				     pcibios_align_resource, dev);
256	if (ret == 0)
257		return 0;
258
259	/*
260	 * If the prefetchable window is only 32 bits wide, we can put
261	 * 64-bit prefetchable resources in it.
262	 */
263	if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
264	     (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
265		ret = pci_bus_alloc_resource(bus, res, size, align, min,
266					     IORESOURCE_PREFETCH,
267					     pcibios_align_resource, dev);
268		if (ret == 0)
269			return 0;
270	}
271
272	/*
273	 * If we didn't find a better match, we can put any memory resource
274	 * in a non-prefetchable window.  If this resource is 32 bits and
275	 * non-prefetchable, the first call already tried the only possibility
276	 * so we don't need to try again.
277	 */
278	if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
279		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
280					     pcibios_align_resource, dev);
281
282	return ret;
283}
284
285static int _pci_assign_resource(struct pci_dev *dev, int resno,
286				resource_size_t size, resource_size_t min_align)
287{
288	struct pci_bus *bus;
289	int ret;
290
291	bus = dev->bus;
292	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
293		if (!bus->parent || !bus->self->transparent)
294			break;
295		bus = bus->parent;
296	}
297
298	return ret;
299}
300
301int pci_assign_resource(struct pci_dev *dev, int resno)
302{
303	struct resource *res = dev->resource + resno;
304	resource_size_t align, size;
305	int ret;
306
307	if (res->flags & IORESOURCE_PCI_FIXED)
308		return 0;
309
310	res->flags |= IORESOURCE_UNSET;
311	align = pci_resource_alignment(dev, res);
312	if (!align) {
313		dev_info(&dev->dev, "BAR %d: can't assign %pR (bogus alignment)\n",
314			 resno, res);
315		return -EINVAL;
316	}
317
318	size = resource_size(res);
319	ret = _pci_assign_resource(dev, resno, size, align);
320
321	/*
322	 * If we failed to assign anything, let's try the address
323	 * where firmware left it.  That at least has a chance of
324	 * working, which is better than just leaving it disabled.
325	 */
326	if (ret < 0) {
327		dev_info(&dev->dev, "BAR %d: no space for %pR\n", resno, res);
328		ret = pci_revert_fw_address(res, dev, resno, size);
329	}
330
331	if (ret < 0) {
332		dev_info(&dev->dev, "BAR %d: failed to assign %pR\n", resno,
333			 res);
334		return ret;
335	}
336
337	res->flags &= ~IORESOURCE_UNSET;
338	res->flags &= ~IORESOURCE_STARTALIGN;
339	dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
340	if (resno < PCI_BRIDGE_RESOURCES)
341		pci_update_resource(dev, resno);
342
343	return 0;
344}
345EXPORT_SYMBOL(pci_assign_resource);
346
347int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
348			resource_size_t min_align)
349{
350	struct resource *res = dev->resource + resno;
351	unsigned long flags;
352	resource_size_t new_size;
353	int ret;
354
355	if (res->flags & IORESOURCE_PCI_FIXED)
356		return 0;
357
358	flags = res->flags;
359	res->flags |= IORESOURCE_UNSET;
360	if (!res->parent) {
361		dev_info(&dev->dev, "BAR %d: can't reassign an unassigned resource %pR\n",
362			 resno, res);
363		return -EINVAL;
364	}
365
366	/* already aligned with min_align */
367	new_size = resource_size(res) + addsize;
368	ret = _pci_assign_resource(dev, resno, new_size, min_align);
369	if (ret) {
370		res->flags = flags;
371		dev_info(&dev->dev, "BAR %d: %pR (failed to expand by %#llx)\n",
372			 resno, res, (unsigned long long) addsize);
373		return ret;
374	}
375
376	res->flags &= ~IORESOURCE_UNSET;
377	res->flags &= ~IORESOURCE_STARTALIGN;
378	dev_info(&dev->dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
379		 resno, res, (unsigned long long) addsize);
380	if (resno < PCI_BRIDGE_RESOURCES)
381		pci_update_resource(dev, resno);
382
383	return 0;
384}
385
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
386int pci_enable_resources(struct pci_dev *dev, int mask)
387{
388	u16 cmd, old_cmd;
389	int i;
390	struct resource *r;
391
392	pci_read_config_word(dev, PCI_COMMAND, &cmd);
393	old_cmd = cmd;
394
395	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
396		if (!(mask & (1 << i)))
397			continue;
398
399		r = &dev->resource[i];
400
401		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
402			continue;
403		if ((i == PCI_ROM_RESOURCE) &&
404				(!(r->flags & IORESOURCE_ROM_ENABLE)))
405			continue;
406
407		if (r->flags & IORESOURCE_UNSET) {
408			dev_err(&dev->dev, "can't enable device: BAR %d %pR not assigned\n",
409				i, r);
410			return -EINVAL;
411		}
412
413		if (!r->parent) {
414			dev_err(&dev->dev, "can't enable device: BAR %d %pR not claimed\n",
415				i, r);
416			return -EINVAL;
417		}
418
419		if (r->flags & IORESOURCE_IO)
420			cmd |= PCI_COMMAND_IO;
421		if (r->flags & IORESOURCE_MEM)
422			cmd |= PCI_COMMAND_MEMORY;
423	}
424
425	if (cmd != old_cmd) {
426		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
427			 old_cmd, cmd);
428		pci_write_config_word(dev, PCI_COMMAND, cmd);
429	}
430	return 0;
431}