1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define pr_fmt(fmt) "PCI: " fmt
4 
5 #include <linux/pci.h>
6 #include <linux/acpi.h>
7 #include <linux/init.h>
8 #include <linux/irq.h>
9 #include <linux/dmi.h>
10 #include <linux/slab.h>
11 #include <linux/pci-acpi.h>
12 #include <asm/numa.h>
13 #include <asm/pci_x86.h>
14 
15 struct pci_root_info {
16 	struct acpi_pci_root_info common;
17 	struct pci_sysdata sd;
18 #ifdef	CONFIG_PCI_MMCONFIG
19 	bool mcfg_added;
20 	u8 start_bus;
21 	u8 end_bus;
22 #endif
23 };
24 
25 bool pci_use_e820 = true;
26 static bool pci_use_crs = true;
27 static bool pci_ignore_seg;
28 
set_use_crs(const struct dmi_system_id * id)29 static int __init set_use_crs(const struct dmi_system_id *id)
30 {
31 	pci_use_crs = true;
32 	return 0;
33 }
34 
set_nouse_crs(const struct dmi_system_id * id)35 static int __init set_nouse_crs(const struct dmi_system_id *id)
36 {
37 	pci_use_crs = false;
38 	return 0;
39 }
40 
set_ignore_seg(const struct dmi_system_id * id)41 static int __init set_ignore_seg(const struct dmi_system_id *id)
42 {
43 	pr_info("%s detected: ignoring ACPI _SEG\n", id->ident);
44 	pci_ignore_seg = true;
45 	return 0;
46 }
47 
set_no_e820(const struct dmi_system_id * id)48 static int __init set_no_e820(const struct dmi_system_id *id)
49 {
50 	pr_info("%s detected: not clipping E820 regions from _CRS\n",
51 	        id->ident);
52 	pci_use_e820 = false;
53 	return 0;
54 }
55 
56 static const struct dmi_system_id pci_crs_quirks[] __initconst = {
57 	/* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
58 	{
59 		.callback = set_use_crs,
60 		.ident = "IBM System x3800",
61 		.matches = {
62 			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
63 			DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
64 		},
65 	},
66 	/* https://bugzilla.kernel.org/show_bug.cgi?id=16007 */
67 	/* 2006 AMD HT/VIA system with two host bridges */
68         {
69 		.callback = set_use_crs,
70 		.ident = "ASRock ALiveSATA2-GLAN",
71 		.matches = {
72 			DMI_MATCH(DMI_PRODUCT_NAME, "ALiveSATA2-GLAN"),
73                 },
74         },
75 	/* https://bugzilla.kernel.org/show_bug.cgi?id=30552 */
76 	/* 2006 AMD HT/VIA system with two host bridges */
77 	{
78 		.callback = set_use_crs,
79 		.ident = "ASUS M2V-MX SE",
80 		.matches = {
81 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
82 			DMI_MATCH(DMI_BOARD_NAME, "M2V-MX SE"),
83 			DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
84 		},
85 	},
86 	/* https://bugzilla.kernel.org/show_bug.cgi?id=42619 */
87 	{
88 		.callback = set_use_crs,
89 		.ident = "MSI MS-7253",
90 		.matches = {
91 			DMI_MATCH(DMI_BOARD_VENDOR, "MICRO-STAR INTERNATIONAL CO., LTD"),
92 			DMI_MATCH(DMI_BOARD_NAME, "MS-7253"),
93 			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies, LTD"),
94 		},
95 	},
96 	/* https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/931368 */
97 	/* https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1033299 */
98 	{
99 		.callback = set_use_crs,
100 		.ident = "Foxconn K8M890-8237A",
101 		.matches = {
102 			DMI_MATCH(DMI_BOARD_VENDOR, "Foxconn"),
103 			DMI_MATCH(DMI_BOARD_NAME, "K8M890-8237A"),
104 			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies, LTD"),
105 		},
106 	},
107 
108 	/* Now for the blacklist.. */
109 
110 	/* https://bugzilla.redhat.com/show_bug.cgi?id=769657 */
111 	{
112 		.callback = set_nouse_crs,
113 		.ident = "Dell Studio 1557",
114 		.matches = {
115 			DMI_MATCH(DMI_BOARD_VENDOR, "Dell Inc."),
116 			DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1557"),
117 			DMI_MATCH(DMI_BIOS_VERSION, "A09"),
118 		},
119 	},
120 	/* https://bugzilla.redhat.com/show_bug.cgi?id=769657 */
121 	{
122 		.callback = set_nouse_crs,
123 		.ident = "Thinkpad SL510",
124 		.matches = {
125 			DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),
126 			DMI_MATCH(DMI_BOARD_NAME, "2847DFG"),
127 			DMI_MATCH(DMI_BIOS_VERSION, "6JET85WW (1.43 )"),
128 		},
129 	},
130 	/* https://bugzilla.kernel.org/show_bug.cgi?id=42606 */
131 	{
132 		.callback = set_nouse_crs,
133 		.ident = "Supermicro X8DTH",
134 		.matches = {
135 			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
136 			DMI_MATCH(DMI_PRODUCT_NAME, "X8DTH-i/6/iF/6F"),
137 			DMI_MATCH(DMI_BIOS_VERSION, "2.0a"),
138 		},
139 	},
140 
141 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15362 */
142 	{
143 		.callback = set_ignore_seg,
144 		.ident = "HP xw9300",
145 		.matches = {
146 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
147 			DMI_MATCH(DMI_PRODUCT_NAME, "HP xw9300 Workstation"),
148 		},
149 	},
150 
151 	/*
152 	 * Many Lenovo models with "IIL" in their DMI_PRODUCT_VERSION have
153 	 * an E820 reserved region that covers the entire 32-bit host
154 	 * bridge memory window from _CRS.  Using the E820 region to clip
155 	 * _CRS means no space is available for hot-added or uninitialized
156 	 * PCI devices.  This typically breaks I2C controllers for touchpads
157 	 * and hot-added Thunderbolt devices.  See the commit log for
158 	 * models known to require this quirk and related bug reports.
159 	 */
160 	{
161 		.callback = set_no_e820,
162 		.ident = "Lenovo *IIL* product version",
163 		.matches = {
164 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
165 			DMI_MATCH(DMI_PRODUCT_VERSION, "IIL"),
166 		},
167 	},
168 
169 	/*
170 	 * The Acer Spin 5 (SP513-54N) has the same E820 reservation covering
171 	 * the entire _CRS 32-bit window issue as the Lenovo *IIL* models.
172 	 * See https://bugs.launchpad.net/bugs/1884232
173 	 */
174 	{
175 		.callback = set_no_e820,
176 		.ident = "Acer Spin 5 (SP513-54N)",
177 		.matches = {
178 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
179 			DMI_MATCH(DMI_PRODUCT_NAME, "Spin SP513-54N"),
180 		},
181 	},
182 
183 	/*
184 	 * Clevo X170KM-G barebones have the same E820 reservation covering
185 	 * the entire _CRS 32-bit window issue as the Lenovo *IIL* models.
186 	 * See https://bugzilla.kernel.org/show_bug.cgi?id=214259
187 	 */
188 	{
189 		.callback = set_no_e820,
190 		.ident = "Clevo X170KM-G Barebone",
191 		.matches = {
192 			DMI_MATCH(DMI_BOARD_NAME, "X170KM-G"),
193 		},
194 	},
195 	{}
196 };
197 
pci_acpi_crs_quirks(void)198 void __init pci_acpi_crs_quirks(void)
199 {
200 	int year = dmi_get_bios_year();
201 
202 	if (year >= 0 && year < 2008 && iomem_resource.end <= 0xffffffff)
203 		pci_use_crs = false;
204 
205 	/*
206 	 * Some firmware includes unusable space (host bridge registers,
207 	 * hidden PCI device BARs, etc) in PCI host bridge _CRS.  This is a
208 	 * firmware defect, and 4dc2287c1805 ("x86: avoid E820 regions when
209 	 * allocating address space") has clipped out the unusable space in
210 	 * the past.
211 	 *
212 	 * But other firmware supplies E820 reserved regions that cover
213 	 * entire _CRS windows, so clipping throws away the entire window,
214 	 * leaving none for hot-added or uninitialized devices.  These E820
215 	 * entries are probably *not* a firmware defect, so disable the
216 	 * clipping by default for post-2022 machines.
217 	 *
218 	 * We already have quirks to disable clipping for pre-2023
219 	 * machines, and we'll likely need quirks to *enable* clipping for
220 	 * post-2022 machines that incorrectly include unusable space in
221 	 * _CRS.
222 	 */
223 	if (year >= 2023)
224 		pci_use_e820 = false;
225 
226 	dmi_check_system(pci_crs_quirks);
227 
228 	/*
229 	 * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
230 	 * takes precedence over anything we figured out above.
231 	 */
232 	if (pci_probe & PCI_ROOT_NO_CRS)
233 		pci_use_crs = false;
234 	else if (pci_probe & PCI_USE__CRS)
235 		pci_use_crs = true;
236 
237 	pr_info("%s host bridge windows from ACPI; if necessary, use \"pci=%s\" and report a bug\n",
238 	        pci_use_crs ? "Using" : "Ignoring",
239 	        pci_use_crs ? "nocrs" : "use_crs");
240 
241 	/* "pci=use_e820"/"pci=no_e820" on the kernel cmdline takes precedence */
242 	if (pci_probe & PCI_NO_E820)
243 		pci_use_e820 = false;
244 	else if (pci_probe & PCI_USE_E820)
245 		pci_use_e820 = true;
246 
247 	pr_info("%s E820 reservations for host bridge windows\n",
248 	        pci_use_e820 ? "Using" : "Ignoring");
249 	if (pci_probe & (PCI_NO_E820 | PCI_USE_E820))
250 		pr_info("Please notify linux-pci@vger.kernel.org so future kernels can do this automatically\n");
251 }
252 
253 #ifdef	CONFIG_PCI_MMCONFIG
check_segment(u16 seg,struct device * dev,char * estr)254 static int check_segment(u16 seg, struct device *dev, char *estr)
255 {
256 	if (seg) {
257 		dev_err(dev, "%s can't access configuration space under this host bridge\n",
258 			estr);
259 		return -EIO;
260 	}
261 
262 	/*
263 	 * Failure in adding MMCFG information is not fatal,
264 	 * just can't access extended configuration space of
265 	 * devices under this host bridge.
266 	 */
267 	dev_warn(dev, "%s can't access extended configuration space under this bridge\n",
268 		 estr);
269 
270 	return 0;
271 }
272 
setup_mcfg_map(struct acpi_pci_root_info * ci)273 static int setup_mcfg_map(struct acpi_pci_root_info *ci)
274 {
275 	int result, seg;
276 	struct pci_root_info *info;
277 	struct acpi_pci_root *root = ci->root;
278 	struct device *dev = &ci->bridge->dev;
279 
280 	info = container_of(ci, struct pci_root_info, common);
281 	info->start_bus = (u8)root->secondary.start;
282 	info->end_bus = (u8)root->secondary.end;
283 	info->mcfg_added = false;
284 	seg = info->sd.domain;
285 
286 	dev_dbg(dev, "%s(%04x %pR ECAM %pa)\n", __func__, seg,
287 		&root->secondary, &root->mcfg_addr);
288 
289 	/* return success if MMCFG is not in use */
290 	if (raw_pci_ext_ops && raw_pci_ext_ops != &pci_mmcfg)
291 		return 0;
292 
293 	if (!(pci_probe & PCI_PROBE_MMCONF))
294 		return check_segment(seg, dev, "MMCONFIG is disabled,");
295 
296 	result = pci_mmconfig_insert(dev, seg, info->start_bus, info->end_bus,
297 				     root->mcfg_addr);
298 	if (result == 0) {
299 		/* enable MMCFG if it hasn't been enabled yet */
300 		if (raw_pci_ext_ops == NULL)
301 			raw_pci_ext_ops = &pci_mmcfg;
302 		info->mcfg_added = true;
303 	} else if (result != -EEXIST)
304 		return check_segment(seg, dev,
305 			 "fail to add MMCONFIG information,");
306 
307 	return 0;
308 }
309 
teardown_mcfg_map(struct acpi_pci_root_info * ci)310 static void teardown_mcfg_map(struct acpi_pci_root_info *ci)
311 {
312 	struct pci_root_info *info;
313 
314 	info = container_of(ci, struct pci_root_info, common);
315 	if (info->mcfg_added) {
316 		pci_mmconfig_delete(info->sd.domain,
317 				    info->start_bus, info->end_bus);
318 		info->mcfg_added = false;
319 	}
320 }
321 #else
setup_mcfg_map(struct acpi_pci_root_info * ci)322 static int setup_mcfg_map(struct acpi_pci_root_info *ci)
323 {
324 	return 0;
325 }
326 
teardown_mcfg_map(struct acpi_pci_root_info * ci)327 static void teardown_mcfg_map(struct acpi_pci_root_info *ci)
328 {
329 }
330 #endif
331 
pci_acpi_root_get_node(struct acpi_pci_root * root)332 static int pci_acpi_root_get_node(struct acpi_pci_root *root)
333 {
334 	int busnum = root->secondary.start;
335 	struct acpi_device *device = root->device;
336 	int node = acpi_get_node(device->handle);
337 
338 	if (node == NUMA_NO_NODE) {
339 		node = x86_pci_root_bus_node(busnum);
340 		if (node != 0 && node != NUMA_NO_NODE)
341 			dev_info(&device->dev, FW_BUG "no _PXM; falling back to node %d from hardware (may be inconsistent with ACPI node numbers)\n",
342 				node);
343 	}
344 	if (node != NUMA_NO_NODE && !node_online(node))
345 		node = NUMA_NO_NODE;
346 
347 	return node;
348 }
349 
pci_acpi_root_init_info(struct acpi_pci_root_info * ci)350 static int pci_acpi_root_init_info(struct acpi_pci_root_info *ci)
351 {
352 	return setup_mcfg_map(ci);
353 }
354 
pci_acpi_root_release_info(struct acpi_pci_root_info * ci)355 static void pci_acpi_root_release_info(struct acpi_pci_root_info *ci)
356 {
357 	teardown_mcfg_map(ci);
358 	kfree(container_of(ci, struct pci_root_info, common));
359 }
360 
361 /*
362  * An IO port or MMIO resource assigned to a PCI host bridge may be
363  * consumed by the host bridge itself or available to its child
364  * bus/devices. The ACPI specification defines a bit (Producer/Consumer)
365  * to tell whether the resource is consumed by the host bridge itself,
366  * but firmware hasn't used that bit consistently, so we can't rely on it.
367  *
368  * On x86 and IA64 platforms, all IO port and MMIO resources are assumed
369  * to be available to child bus/devices except one special case:
370  *     IO port [0xCF8-0xCFF] is consumed by the host bridge itself
371  *     to access PCI configuration space.
372  *
373  * So explicitly filter out PCI CFG IO ports[0xCF8-0xCFF].
374  */
resource_is_pcicfg_ioport(struct resource * res)375 static bool resource_is_pcicfg_ioport(struct resource *res)
376 {
377 	return (res->flags & IORESOURCE_IO) &&
378 		res->start == 0xCF8 && res->end == 0xCFF;
379 }
380 
pci_acpi_root_prepare_resources(struct acpi_pci_root_info * ci)381 static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci)
382 {
383 	struct acpi_device *device = ci->bridge;
384 	int busnum = ci->root->secondary.start;
385 	struct resource_entry *entry, *tmp;
386 	int status;
387 
388 	status = acpi_pci_probe_root_resources(ci);
389 
390 	if (pci_use_crs) {
391 		resource_list_for_each_entry_safe(entry, tmp, &ci->resources)
392 			if (resource_is_pcicfg_ioport(entry->res))
393 				resource_list_destroy_entry(entry);
394 		return status;
395 	}
396 
397 	resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
398 		dev_printk(KERN_DEBUG, &device->dev,
399 			   "host bridge window %pR (ignored)\n", entry->res);
400 		resource_list_destroy_entry(entry);
401 	}
402 	x86_pci_root_bus_resources(busnum, &ci->resources);
403 
404 	return 0;
405 }
406 
407 static struct acpi_pci_root_ops acpi_pci_root_ops = {
408 	.pci_ops = &pci_root_ops,
409 	.init_info = pci_acpi_root_init_info,
410 	.release_info = pci_acpi_root_release_info,
411 	.prepare_resources = pci_acpi_root_prepare_resources,
412 };
413 
pci_acpi_scan_root(struct acpi_pci_root * root)414 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
415 {
416 	int domain = root->segment;
417 	int busnum = root->secondary.start;
418 	int node = pci_acpi_root_get_node(root);
419 	struct pci_bus *bus;
420 
421 	if (pci_ignore_seg)
422 		root->segment = domain = 0;
423 
424 	if (domain && !pci_domains_supported) {
425 		pr_warn("pci_bus %04x:%02x: ignored (multiple domains not supported)\n",
426 		        domain, busnum);
427 		return NULL;
428 	}
429 
430 	bus = pci_find_bus(domain, busnum);
431 	if (bus) {
432 		/*
433 		 * If the desired bus has been scanned already, replace
434 		 * its bus->sysdata.
435 		 */
436 		struct pci_sysdata sd = {
437 			.domain = domain,
438 			.node = node,
439 			.companion = root->device
440 		};
441 
442 		memcpy(bus->sysdata, &sd, sizeof(sd));
443 	} else {
444 		struct pci_root_info *info;
445 
446 		info = kzalloc(sizeof(*info), GFP_KERNEL);
447 		if (!info)
448 			dev_err(&root->device->dev,
449 				"pci_bus %04x:%02x: ignored (out of memory)\n",
450 				domain, busnum);
451 		else {
452 			info->sd.domain = domain;
453 			info->sd.node = node;
454 			info->sd.companion = root->device;
455 			bus = acpi_pci_root_create(root, &acpi_pci_root_ops,
456 						   &info->common, &info->sd);
457 		}
458 	}
459 
460 	/* After the PCI-E bus has been walked and all devices discovered,
461 	 * configure any settings of the fabric that might be necessary.
462 	 */
463 	if (bus) {
464 		struct pci_bus *child;
465 		list_for_each_entry(child, &bus->children, node)
466 			pcie_bus_configure_settings(child);
467 	}
468 
469 	return bus;
470 }
471 
pcibios_root_bridge_prepare(struct pci_host_bridge * bridge)472 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
473 {
474 	/*
475 	 * We pass NULL as parent to pci_create_root_bus(), so if it is not NULL
476 	 * here, pci_create_root_bus() has been called by someone else and
477 	 * sysdata is likely to be different from what we expect.  Let it go in
478 	 * that case.
479 	 */
480 	if (!bridge->dev.parent) {
481 		struct pci_sysdata *sd = bridge->bus->sysdata;
482 		ACPI_COMPANION_SET(&bridge->dev, sd->companion);
483 	}
484 	return 0;
485 }
486 
pci_acpi_init(void)487 int __init pci_acpi_init(void)
488 {
489 	struct pci_dev *dev = NULL;
490 
491 	if (acpi_noirq)
492 		return -ENODEV;
493 
494 	pr_info("Using ACPI for IRQ routing\n");
495 	acpi_irq_penalty_init();
496 	pcibios_enable_irq = acpi_pci_irq_enable;
497 	pcibios_disable_irq = acpi_pci_irq_disable;
498 	x86_init.pci.init_irq = x86_init_noop;
499 
500 	if (pci_routeirq) {
501 		/*
502 		 * PCI IRQ routing is set up by pci_enable_device(), but we
503 		 * also do it here in case there are still broken drivers that
504 		 * don't use pci_enable_device().
505 		 */
506 		pr_info("Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
507 		for_each_pci_dev(dev)
508 			acpi_pci_irq_enable(dev);
509 	}
510 
511 	return 0;
512 }
513