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v3.15
 
  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/init.h>
 20#include <linux/kernel.h>
 21#include <linux/export.h>
 22#include <linux/pci.h>
 23#include <linux/errno.h>
 24#include <linux/ioport.h>
 25#include <linux/cache.h>
 26#include <linux/slab.h>
 27#include "pci.h"
 28
 29
 30void pci_update_resource(struct pci_dev *dev, int resno)
 31{
 32	struct pci_bus_region region;
 33	bool disable;
 34	u16 cmd;
 35	u32 new, check, mask;
 36	int reg;
 37	enum pci_bar_type type;
 38	struct resource *res = dev->resource + resno;
 39
 
 
 
 
 40	/*
 41	 * Ignore resources for unimplemented BARs and unused resource slots
 42	 * for 64 bit BARs.
 43	 */
 44	if (!res->flags)
 45		return;
 46
 47	if (res->flags & IORESOURCE_UNSET)
 48		return;
 49
 50	/*
 51	 * Ignore non-moveable resources.  This might be legacy resources for
 52	 * which no functional BAR register exists or another important
 53	 * system resource we shouldn't move around.
 54	 */
 55	if (res->flags & IORESOURCE_PCI_FIXED)
 56		return;
 57
 58	pcibios_resource_to_bus(dev->bus, &region, res);
 
 59
 60	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
 61	if (res->flags & IORESOURCE_IO)
 62		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
 63	else
 
 
 
 64		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 
 
 65
 66	reg = pci_resource_bar(dev, resno, &type);
 67	if (!reg)
 68		return;
 69	if (type != pci_bar_unknown) {
 70		if (!(res->flags & IORESOURCE_ROM_ENABLE))
 
 
 
 
 
 
 
 
 
 71			return;
 72		new |= PCI_ROM_ADDRESS_ENABLE;
 73	}
 
 
 
 
 74
 75	/*
 76	 * We can't update a 64-bit BAR atomically, so when possible,
 77	 * disable decoding so that a half-updated BAR won't conflict
 78	 * with another device.
 79	 */
 80	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
 81	if (disable) {
 82		pci_read_config_word(dev, PCI_COMMAND, &cmd);
 83		pci_write_config_word(dev, PCI_COMMAND,
 84				      cmd & ~PCI_COMMAND_MEMORY);
 85	}
 86
 87	pci_write_config_dword(dev, reg, new);
 88	pci_read_config_dword(dev, reg, &check);
 89
 90	if ((new ^ check) & mask) {
 91		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
 92			resno, new, check);
 93	}
 94
 95	if (res->flags & IORESOURCE_MEM_64) {
 96		new = region.start >> 16 >> 16;
 97		pci_write_config_dword(dev, reg + 4, new);
 98		pci_read_config_dword(dev, reg + 4, &check);
 99		if (check != new) {
100			dev_err(&dev->dev, "BAR %d: error updating "
101			       "(high %#08x != %#08x)\n", resno, new, check);
102		}
103	}
104
105	if (disable)
106		pci_write_config_word(dev, PCI_COMMAND, cmd);
107}
108
 
 
 
 
 
 
 
 
 
 
109int pci_claim_resource(struct pci_dev *dev, int resource)
110{
111	struct resource *res = &dev->resource[resource];
112	struct resource *root, *conflict;
113
114	if (res->flags & IORESOURCE_UNSET) {
115		dev_info(&dev->dev, "can't claim BAR %d %pR: no address assigned\n",
116			 resource, res);
117		return -EINVAL;
118	}
119
 
 
 
 
 
 
 
 
120	root = pci_find_parent_resource(dev, res);
121	if (!root) {
122		dev_info(&dev->dev, "can't claim BAR %d %pR: no compatible bridge window\n",
123			 resource, res);
 
124		return -EINVAL;
125	}
126
127	conflict = request_resource_conflict(root, res);
128	if (conflict) {
129		dev_info(&dev->dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
130			 resource, res, conflict->name, conflict);
 
131		return -EBUSY;
132	}
133
134	return 0;
135}
136EXPORT_SYMBOL(pci_claim_resource);
137
138void pci_disable_bridge_window(struct pci_dev *dev)
139{
140	dev_info(&dev->dev, "disabling bridge mem windows\n");
141
142	/* MMIO Base/Limit */
143	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
144
145	/* Prefetchable MMIO Base/Limit */
146	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
147	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
148	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
149}
150
151/*
152 * Generic function that returns a value indicating that the device's
153 * original BIOS BAR address was not saved and so is not available for
154 * reinstatement.
155 *
156 * Can be over-ridden by architecture specific code that implements
157 * reinstatement functionality rather than leaving it disabled when
158 * normal allocation attempts fail.
159 */
160resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
161{
162	return 0;
163}
164
165static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
166		int resno, resource_size_t size)
167{
168	struct resource *root, *conflict;
169	resource_size_t fw_addr, start, end;
170	int ret = 0;
171
172	fw_addr = pcibios_retrieve_fw_addr(dev, resno);
173	if (!fw_addr)
174		return 1;
175
176	start = res->start;
177	end = res->end;
178	res->start = fw_addr;
179	res->end = res->start + size - 1;
 
180
181	root = pci_find_parent_resource(dev, res);
182	if (!root) {
 
 
 
 
 
 
 
 
 
 
 
183		if (res->flags & IORESOURCE_IO)
184			root = &ioport_resource;
185		else
186			root = &iomem_resource;
187	}
188
189	dev_info(&dev->dev, "BAR %d: trying firmware assignment %pR\n",
190		 resno, res);
191	conflict = request_resource_conflict(root, res);
192	if (conflict) {
193		dev_info(&dev->dev,
194			 "BAR %d: %pR conflicts with %s %pR\n", resno,
195			 res, conflict->name, conflict);
196		res->start = start;
197		res->end = end;
198		ret = 1;
 
199	}
200	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
201}
202
203static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
204		int resno, resource_size_t size, resource_size_t align)
205{
206	struct resource *res = dev->resource + resno;
207	resource_size_t min;
208	int ret;
209
210	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
211
212	/* First, try exact prefetching match.. */
 
 
 
 
 
 
213	ret = pci_bus_alloc_resource(bus, res, size, align, min,
214				     IORESOURCE_PREFETCH,
215				     pcibios_align_resource, dev);
 
 
216
217	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
218		/*
219		 * That failed.
220		 *
221		 * But a prefetching area can handle a non-prefetching
222		 * window (it will just not perform as well).
223		 */
224		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
225					     pcibios_align_resource, dev);
 
 
226	}
 
 
 
 
 
 
 
 
 
 
 
227	return ret;
228}
229
230static int _pci_assign_resource(struct pci_dev *dev, int resno,
231				resource_size_t size, resource_size_t min_align)
232{
233	struct resource *res = dev->resource + resno;
234	struct pci_bus *bus;
235	int ret;
236	char *type;
237
238	bus = dev->bus;
239	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
240		if (!bus->parent || !bus->self->transparent)
241			break;
242		bus = bus->parent;
243	}
244
245	if (ret) {
246		if (res->flags & IORESOURCE_MEM)
247			if (res->flags & IORESOURCE_PREFETCH)
248				type = "mem pref";
249			else
250				type = "mem";
251		else if (res->flags & IORESOURCE_IO)
252			type = "io";
253		else
254			type = "unknown";
255		dev_info(&dev->dev,
256			 "BAR %d: can't assign %s (size %#llx)\n",
257			 resno, type, (unsigned long long) resource_size(res));
258	}
259
260	return ret;
261}
262
263int pci_assign_resource(struct pci_dev *dev, int resno)
264{
265	struct resource *res = dev->resource + resno;
266	resource_size_t align, size;
267	int ret;
268
 
 
 
269	res->flags |= IORESOURCE_UNSET;
270	align = pci_resource_alignment(dev, res);
271	if (!align) {
272		dev_info(&dev->dev, "BAR %d: can't assign %pR "
273			 "(bogus alignment)\n", resno, res);
274		return -EINVAL;
275	}
276
277	size = resource_size(res);
278	ret = _pci_assign_resource(dev, resno, size, align);
279
280	/*
281	 * If we failed to assign anything, let's try the address
282	 * where firmware left it.  That at least has a chance of
283	 * working, which is better than just leaving it disabled.
284	 */
285	if (ret < 0)
 
286		ret = pci_revert_fw_address(res, dev, resno, size);
 
287
288	if (!ret) {
289		res->flags &= ~IORESOURCE_UNSET;
290		res->flags &= ~IORESOURCE_STARTALIGN;
291		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
292		if (resno < PCI_BRIDGE_RESOURCES)
293			pci_update_resource(dev, resno);
294	}
295	return ret;
 
 
 
 
 
 
 
296}
 
297
298int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
299			resource_size_t min_align)
300{
301	struct resource *res = dev->resource + resno;
 
302	resource_size_t new_size;
303	int ret;
304
 
 
 
 
305	res->flags |= IORESOURCE_UNSET;
306	if (!res->parent) {
307		dev_info(&dev->dev, "BAR %d: can't reassign an unassigned resource %pR "
308			 "\n", resno, res);
309		return -EINVAL;
310	}
311
312	/* already aligned with min_align */
313	new_size = resource_size(res) + addsize;
314	ret = _pci_assign_resource(dev, resno, new_size, min_align);
315	if (!ret) {
316		res->flags &= ~IORESOURCE_UNSET;
317		res->flags &= ~IORESOURCE_STARTALIGN;
318		dev_info(&dev->dev, "BAR %d: reassigned %pR\n", resno, res);
319		if (resno < PCI_BRIDGE_RESOURCES)
320			pci_update_resource(dev, resno);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
321	}
 
 
 
 
 
322	return ret;
323}
 
324
325int pci_enable_resources(struct pci_dev *dev, int mask)
326{
327	u16 cmd, old_cmd;
328	int i;
329	struct resource *r;
330
331	pci_read_config_word(dev, PCI_COMMAND, &cmd);
332	old_cmd = cmd;
333
334	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
335		if (!(mask & (1 << i)))
336			continue;
337
338		r = &dev->resource[i];
339
340		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
341			continue;
342		if ((i == PCI_ROM_RESOURCE) &&
343				(!(r->flags & IORESOURCE_ROM_ENABLE)))
344			continue;
345
346		if (r->flags & IORESOURCE_UNSET) {
347			dev_err(&dev->dev, "can't enable device: BAR %d %pR not assigned\n",
348				i, r);
349			return -EINVAL;
350		}
351
352		if (!r->parent) {
353			dev_err(&dev->dev, "can't enable device: BAR %d %pR not claimed\n",
354				i, r);
355			return -EINVAL;
356		}
357
358		if (r->flags & IORESOURCE_IO)
359			cmd |= PCI_COMMAND_IO;
360		if (r->flags & IORESOURCE_MEM)
361			cmd |= PCI_COMMAND_MEMORY;
362	}
363
364	if (cmd != old_cmd) {
365		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
366			 old_cmd, cmd);
367		pci_write_config_word(dev, PCI_COMMAND, cmd);
368	}
369	return 0;
370}
v6.2
  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		 * But we must update ROM BAR for buggy devices where even a
 79		 * disabled ROM can conflict with other BARs.
 80		 */
 81		if (!(res->flags & IORESOURCE_ROM_ENABLE) &&
 82		    !dev->rom_bar_overlap)
 83			return;
 84
 85		reg = dev->rom_base_reg;
 86		if (res->flags & IORESOURCE_ROM_ENABLE)
 87			new |= PCI_ROM_ADDRESS_ENABLE;
 88	} else
 89		return;
 90
 91	/*
 92	 * We can't update a 64-bit BAR atomically, so when possible,
 93	 * disable decoding so that a half-updated BAR won't conflict
 94	 * with another device.
 95	 */
 96	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
 97	if (disable) {
 98		pci_read_config_word(dev, PCI_COMMAND, &cmd);
 99		pci_write_config_word(dev, PCI_COMMAND,
100				      cmd & ~PCI_COMMAND_MEMORY);
101	}
102
103	pci_write_config_dword(dev, reg, new);
104	pci_read_config_dword(dev, reg, &check);
105
106	if ((new ^ check) & mask) {
107		pci_err(dev, "BAR %d: error updating (%#08x != %#08x)\n",
108			resno, new, check);
109	}
110
111	if (res->flags & IORESOURCE_MEM_64) {
112		new = region.start >> 16 >> 16;
113		pci_write_config_dword(dev, reg + 4, new);
114		pci_read_config_dword(dev, reg + 4, &check);
115		if (check != new) {
116			pci_err(dev, "BAR %d: error updating (high %#08x != %#08x)\n",
117				resno, new, check);
118		}
119	}
120
121	if (disable)
122		pci_write_config_word(dev, PCI_COMMAND, cmd);
123}
124
125void pci_update_resource(struct pci_dev *dev, int resno)
126{
127	if (resno <= PCI_ROM_RESOURCE)
128		pci_std_update_resource(dev, resno);
129#ifdef CONFIG_PCI_IOV
130	else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
131		pci_iov_update_resource(dev, resno);
132#endif
133}
134
135int pci_claim_resource(struct pci_dev *dev, int resource)
136{
137	struct resource *res = &dev->resource[resource];
138	struct resource *root, *conflict;
139
140	if (res->flags & IORESOURCE_UNSET) {
141		pci_info(dev, "can't claim BAR %d %pR: no address assigned\n",
142			 resource, res);
143		return -EINVAL;
144	}
145
146	/*
147	 * If we have a shadow copy in RAM, the PCI device doesn't respond
148	 * to the shadow range, so we don't need to claim it, and upstream
149	 * bridges don't need to route the range to the device.
150	 */
151	if (res->flags & IORESOURCE_ROM_SHADOW)
152		return 0;
153
154	root = pci_find_parent_resource(dev, res);
155	if (!root) {
156		pci_info(dev, "can't claim BAR %d %pR: no compatible bridge window\n",
157			 resource, res);
158		res->flags |= IORESOURCE_UNSET;
159		return -EINVAL;
160	}
161
162	conflict = request_resource_conflict(root, res);
163	if (conflict) {
164		pci_info(dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
165			 resource, res, conflict->name, conflict);
166		res->flags |= IORESOURCE_UNSET;
167		return -EBUSY;
168	}
169
170	return 0;
171}
172EXPORT_SYMBOL(pci_claim_resource);
173
174void pci_disable_bridge_window(struct pci_dev *dev)
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		/*
218		 * If dev is behind a bridge, accesses will only reach it
219		 * if res is inside the relevant bridge window.
220		 */
221		if (pci_upstream_bridge(dev))
222			return -ENXIO;
223
224		/*
225		 * On the root bus, assume the host bridge will forward
226		 * everything.
227		 */
228		if (res->flags & IORESOURCE_IO)
229			root = &ioport_resource;
230		else
231			root = &iomem_resource;
232	}
233
234	pci_info(dev, "BAR %d: trying firmware assignment %pR\n",
235		 resno, res);
236	conflict = request_resource_conflict(root, res);
237	if (conflict) {
238		pci_info(dev, "BAR %d: %pR conflicts with %s %pR\n",
239			 resno, res, conflict->name, conflict);
 
240		res->start = start;
241		res->end = end;
242		res->flags |= IORESOURCE_UNSET;
243		return -EBUSY;
244	}
245	return 0;
246}
247
248/*
249 * We don't have to worry about legacy ISA devices, so nothing to do here.
250 * This is marked as __weak because multiple architectures define it; it should
251 * eventually go away.
252 */
253resource_size_t __weak pcibios_align_resource(void *data,
254					      const struct resource *res,
255					      resource_size_t size,
256					      resource_size_t align)
257{
258       return res->start;
259}
260
261static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
262		int resno, resource_size_t size, resource_size_t align)
263{
264	struct resource *res = dev->resource + resno;
265	resource_size_t min;
266	int ret;
267
268	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
269
270	/*
271	 * First, try exact prefetching match.  Even if a 64-bit
272	 * prefetchable bridge window is below 4GB, we can't put a 32-bit
273	 * prefetchable resource in it because pbus_size_mem() assumes a
274	 * 64-bit window will contain no 32-bit resources.  If we assign
275	 * things differently than they were sized, not everything will fit.
276	 */
277	ret = pci_bus_alloc_resource(bus, res, size, align, min,
278				     IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
279				     pcibios_align_resource, dev);
280	if (ret == 0)
281		return 0;
282
283	/*
284	 * If the prefetchable window is only 32 bits wide, we can put
285	 * 64-bit prefetchable resources in it.
286	 */
287	if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
288	     (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
289		ret = pci_bus_alloc_resource(bus, res, size, align, min,
290					     IORESOURCE_PREFETCH,
291					     pcibios_align_resource, dev);
292		if (ret == 0)
293			return 0;
294	}
295
296	/*
297	 * If we didn't find a better match, we can put any memory resource
298	 * in a non-prefetchable window.  If this resource is 32 bits and
299	 * non-prefetchable, the first call already tried the only possibility
300	 * so we don't need to try again.
301	 */
302	if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
303		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
304					     pcibios_align_resource, dev);
305
306	return ret;
307}
308
309static int _pci_assign_resource(struct pci_dev *dev, int resno,
310				resource_size_t size, resource_size_t min_align)
311{
 
312	struct pci_bus *bus;
313	int ret;
 
314
315	bus = dev->bus;
316	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
317		if (!bus->parent || !bus->self->transparent)
318			break;
319		bus = bus->parent;
320	}
321
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
322	return ret;
323}
324
325int pci_assign_resource(struct pci_dev *dev, int resno)
326{
327	struct resource *res = dev->resource + resno;
328	resource_size_t align, size;
329	int ret;
330
331	if (res->flags & IORESOURCE_PCI_FIXED)
332		return 0;
333
334	res->flags |= IORESOURCE_UNSET;
335	align = pci_resource_alignment(dev, res);
336	if (!align) {
337		pci_info(dev, "BAR %d: can't assign %pR (bogus alignment)\n",
338			 resno, res);
339		return -EINVAL;
340	}
341
342	size = resource_size(res);
343	ret = _pci_assign_resource(dev, resno, size, align);
344
345	/*
346	 * If we failed to assign anything, let's try the address
347	 * where firmware left it.  That at least has a chance of
348	 * working, which is better than just leaving it disabled.
349	 */
350	if (ret < 0) {
351		pci_info(dev, "BAR %d: no space for %pR\n", resno, res);
352		ret = pci_revert_fw_address(res, dev, resno, size);
353	}
354
355	if (ret < 0) {
356		pci_info(dev, "BAR %d: failed to assign %pR\n", resno, res);
357		return ret;
 
 
 
358	}
359
360	res->flags &= ~IORESOURCE_UNSET;
361	res->flags &= ~IORESOURCE_STARTALIGN;
362	pci_info(dev, "BAR %d: assigned %pR\n", resno, res);
363	if (resno < PCI_BRIDGE_RESOURCES)
364		pci_update_resource(dev, resno);
365
366	return 0;
367}
368EXPORT_SYMBOL(pci_assign_resource);
369
370int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
371			resource_size_t min_align)
372{
373	struct resource *res = dev->resource + resno;
374	unsigned long flags;
375	resource_size_t new_size;
376	int ret;
377
378	if (res->flags & IORESOURCE_PCI_FIXED)
379		return 0;
380
381	flags = res->flags;
382	res->flags |= IORESOURCE_UNSET;
383	if (!res->parent) {
384		pci_info(dev, "BAR %d: can't reassign an unassigned resource %pR\n",
385			 resno, res);
386		return -EINVAL;
387	}
388
389	/* already aligned with min_align */
390	new_size = resource_size(res) + addsize;
391	ret = _pci_assign_resource(dev, resno, new_size, min_align);
392	if (ret) {
393		res->flags = flags;
394		pci_info(dev, "BAR %d: %pR (failed to expand by %#llx)\n",
395			 resno, res, (unsigned long long) addsize);
396		return ret;
397	}
398
399	res->flags &= ~IORESOURCE_UNSET;
400	res->flags &= ~IORESOURCE_STARTALIGN;
401	pci_info(dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
402		 resno, res, (unsigned long long) addsize);
403	if (resno < PCI_BRIDGE_RESOURCES)
404		pci_update_resource(dev, resno);
405
406	return 0;
407}
408
409void pci_release_resource(struct pci_dev *dev, int resno)
410{
411	struct resource *res = dev->resource + resno;
412
413	pci_info(dev, "BAR %d: releasing %pR\n", resno, res);
414
415	if (!res->parent)
416		return;
417
418	release_resource(res);
419	res->end = resource_size(res) - 1;
420	res->start = 0;
421	res->flags |= IORESOURCE_UNSET;
422}
423EXPORT_SYMBOL(pci_release_resource);
424
425int pci_resize_resource(struct pci_dev *dev, int resno, int size)
426{
427	struct resource *res = dev->resource + resno;
428	struct pci_host_bridge *host;
429	int old, ret;
430	u32 sizes;
431	u16 cmd;
432
433	/* Check if we must preserve the firmware's resource assignment */
434	host = pci_find_host_bridge(dev->bus);
435	if (host->preserve_config)
436		return -ENOTSUPP;
437
438	/* Make sure the resource isn't assigned before resizing it. */
439	if (!(res->flags & IORESOURCE_UNSET))
440		return -EBUSY;
441
442	pci_read_config_word(dev, PCI_COMMAND, &cmd);
443	if (cmd & PCI_COMMAND_MEMORY)
444		return -EBUSY;
445
446	sizes = pci_rebar_get_possible_sizes(dev, resno);
447	if (!sizes)
448		return -ENOTSUPP;
449
450	if (!(sizes & BIT(size)))
451		return -EINVAL;
452
453	old = pci_rebar_get_current_size(dev, resno);
454	if (old < 0)
455		return old;
456
457	ret = pci_rebar_set_size(dev, resno, size);
458	if (ret)
459		return ret;
460
461	res->end = res->start + pci_rebar_size_to_bytes(size) - 1;
462
463	/* Check if the new config works by trying to assign everything. */
464	if (dev->bus->self) {
465		ret = pci_reassign_bridge_resources(dev->bus->self, res->flags);
466		if (ret)
467			goto error_resize;
468	}
469	return 0;
470
471error_resize:
472	pci_rebar_set_size(dev, resno, old);
473	res->end = res->start + pci_rebar_size_to_bytes(old) - 1;
474	return ret;
475}
476EXPORT_SYMBOL(pci_resize_resource);
477
478int pci_enable_resources(struct pci_dev *dev, int mask)
479{
480	u16 cmd, old_cmd;
481	int i;
482	struct resource *r;
483
484	pci_read_config_word(dev, PCI_COMMAND, &cmd);
485	old_cmd = cmd;
486
487	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
488		if (!(mask & (1 << i)))
489			continue;
490
491		r = &dev->resource[i];
492
493		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
494			continue;
495		if ((i == PCI_ROM_RESOURCE) &&
496				(!(r->flags & IORESOURCE_ROM_ENABLE)))
497			continue;
498
499		if (r->flags & IORESOURCE_UNSET) {
500			pci_err(dev, "can't enable device: BAR %d %pR not assigned\n",
501				i, r);
502			return -EINVAL;
503		}
504
505		if (!r->parent) {
506			pci_err(dev, "can't enable device: BAR %d %pR not claimed\n",
507				i, r);
508			return -EINVAL;
509		}
510
511		if (r->flags & IORESOURCE_IO)
512			cmd |= PCI_COMMAND_IO;
513		if (r->flags & IORESOURCE_MEM)
514			cmd |= PCI_COMMAND_MEMORY;
515	}
516
517	if (cmd != old_cmd) {
518		pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
 
519		pci_write_config_word(dev, PCI_COMMAND, cmd);
520	}
521	return 0;
522}