x86/PCI: use host bridge _CRS info by default on 2008 and newer machines

The main benefit of using ACPI host bridge window information is that we can do better resource allocation in systems with multiple host bridges, e.g., http://bugzilla.kernel.org/show_bug.cgi?id=14183 Sometimes we need _CRS information even if we only have one host bridge, e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681 Most of these systems are relatively new, so this patch turns on "pci=use_crs" only on machines with a BIOS date of 2008 or newer. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

x86/PCI: use host bridge _CRS info by default on 2008 and newer machines
The main benefit of using ACPI host bridge window information is that we can do better resource allocation in systems with multiple host bridges, e.g., http://bugzilla.kernel.org/show_bug.cgi?id=14183 Sometimes we need _CRS information even if we only have one host bridge, e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681 Most of these systems are relatively new, so this patch turns on "pci=use_crs" only on machines with a BIOS date of 2008 or newer. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bjorn Helgaas · Jesse Barnes
1 parent 2fe2abf896
Showing 7 changed files with 60 additions and 8 deletions Side-by-side Diff
Documentation/kernel-parameters.txt
arch/ia64/include/asm/acpi.h
arch/x86/include/asm/pci_x86.h
arch/x86/pci/acpi.c
arch/x86/pci/common.c
drivers/acpi/pci_root.c
include/acpi/acpi_drivers.h
@@ -1948,8 +1948,12 @@
 				IRQ routing is enabled.
 		noacpi		[X86] Do not use ACPI for IRQ routing
 				or for PCI scanning.
-		use_crs		[X86] Use _CRS for PCI resource
-				allocation.
+		use_crs		[X86] Use PCI host bridge window information
+				from ACPI.  On BIOSes from 2008 or later, this
+				is enabled by default.  If you need to use this,
+				please report a bug.
+		nocrs		[X86] Ignore PCI host bridge windows from ACPI.
+			        If you need to use this, please report a bug.
 		routeirq	Do IRQ routing for all PCI devices.
 				This is normally done in pci_enable_device(),
 				so this option is a temporary workaround
@@ -98,6 +98,7 @@
 #endif
 #define acpi_processor_cstate_check(x) (x) /* no idle limits on IA64 :) */
 static inline void disable_acpi(void) { }
+static inline void pci_acpi_crs_quirks(void) { }
  
 const char *acpi_get_sysname (void);
 int acpi_request_vector (u32 int_type);
@@ -29,6 +29,7 @@
 #define PCI_CHECK_ENABLE_AMD_MMCONF	0x20000
 #define PCI_HAS_IO_ECS		0x40000
 #define PCI_NOASSIGN_ROMS	0x80000
+#define PCI_ROOT_NO_CRS		0x100000
  
 extern unsigned int pci_probe;
 extern unsigned long pirq_table_addr;
@@ -15,6 +15,51 @@
 	int busnum;
 };
  
+static bool pci_use_crs = true;
+
+static int __init set_use_crs(const struct dmi_system_id *id)
+{
+	pci_use_crs = true;
+	return 0;
+}
+
+static const struct dmi_system_id pci_use_crs_table[] __initconst = {
+	/* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
+	{
+		.callback = set_use_crs,
+		.ident = "IBM System x3800",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
+		},
+	},
+	{}
+};
+
+void __init pci_acpi_crs_quirks(void)
+{
+	int year;
+
+	if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
+		pci_use_crs = false;
+
+	dmi_check_system(pci_use_crs_table);
+
+	/*
+	 * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
+	 * takes precedence over anything we figured out above.
+	 */
+	if (pci_probe & PCI_ROOT_NO_CRS)
+		pci_use_crs = false;
+	else if (pci_probe & PCI_USE__CRS)
+		pci_use_crs = true;
+
+	printk(KERN_INFO "PCI: %s host bridge windows from ACPI; "
+	       "if necessary, use \"pci=%s\" and report a bug\n",
+	       pci_use_crs ? "Using" : "Ignoring",
+	       pci_use_crs ? "nocrs" : "use_crs");
+}
+
 static acpi_status
 resource_to_addr(struct acpi_resource *resource,
 			struct acpi_resource_address64 *addr)
@@ -106,7 +151,7 @@
 	res->child = NULL;
 	align_resource(info->bridge, res);
  
-	if (!(pci_probe & PCI_USE__CRS)) {
+	if (!pci_use_crs) {
 		dev_printk(KERN_DEBUG, &info->bridge->dev,
 			   "host bridge window %pR (ignored)\n", res);
 		return AE_OK;
  
@@ -137,12 +182,8 @@
 	struct pci_root_info info;
 	size_t size;
  
-	if (pci_probe & PCI_USE__CRS)
+	if (pci_use_crs)
 		pci_bus_remove_resources(bus);
-	else
-		dev_info(&device->dev,
-			 "ignoring host bridge windows from ACPI; "
-			 "boot with \"pci=use_crs\" to use them\n");
  
 	info.bridge = device;
 	info.bus = bus;
@@ -520,6 +520,9 @@
 	} else if (!strcmp(str, "use_crs")) {
 		pci_probe |= PCI_USE__CRS;
 		return NULL;
+	} else if (!strcmp(str, "nocrs")) {
+		pci_probe |= PCI_ROOT_NO_CRS;
+		return NULL;
 	} else if (!strcmp(str, "earlydump")) {
 		pci_early_dump_regs = 1;
 		return NULL;
@@ -566,6 +566,7 @@
 	if (acpi_pci_disabled)
 		return 0;
  
+	pci_acpi_crs_quirks();
 	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 		return -ENODEV;
  
@@ -104,6 +104,7 @@
  
 struct pci_bus *pci_acpi_scan_root(struct acpi_device *device, int domain,
 				   int bus);
+void pci_acpi_crs_quirks(void);
  
 /* --------------------------------------------------------------------------
                                     Processor
...	...	@@ -1948,8 +1948,12 @@
1948	1948	IRQ routing is enabled.
1949	1949	noacpi [X86] Do not use ACPI for IRQ routing
1950	1950	or for PCI scanning.
1951		- use_crs [X86] Use _CRS for PCI resource
1952		- allocation.
	1951	+ use_crs [X86] Use PCI host bridge window information
	1952	+ from ACPI. On BIOSes from 2008 or later, this
	1953	+ is enabled by default. If you need to use this,
	1954	+ please report a bug.
	1955	+ nocrs [X86] Ignore PCI host bridge windows from ACPI.
	1956	+ If you need to use this, please report a bug.
1953	1957	routeirq Do IRQ routing for all PCI devices.
1954	1958	This is normally done in pci_enable_device(),
1955	1959	so this option is a temporary workaround
...	...	@@ -98,6 +98,7 @@
98	98	#endif
99	99	#define acpi_processor_cstate_check(x) (x) /* no idle limits on IA64 :) */
100	100	static inline void disable_acpi(void) { }
	101	+static inline void pci_acpi_crs_quirks(void) { }
101	102
102	103	const char *acpi_get_sysname (void);
103	104	int acpi_request_vector (u32 int_type);
...	...	@@ -29,6 +29,7 @@
29	29	#define PCI_CHECK_ENABLE_AMD_MMCONF 0x20000
30	30	#define PCI_HAS_IO_ECS 0x40000
31	31	#define PCI_NOASSIGN_ROMS 0x80000
	32	+#define PCI_ROOT_NO_CRS 0x100000
32	33
33	34	extern unsigned int pci_probe;
34	35	extern unsigned long pirq_table_addr;
...	...	@@ -15,6 +15,51 @@
15	15	int busnum;
16	16	};
17	17
	18	+static bool pci_use_crs = true;
	19	+
	20	+static int __init set_use_crs(const struct dmi_system_id *id)
	21	+{
	22	+ pci_use_crs = true;
	23	+ return 0;
	24	+}
	25	+
	26	+static const struct dmi_system_id pci_use_crs_table[] __initconst = {
	27	+ /* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
	28	+ {
	29	+ .callback = set_use_crs,
	30	+ .ident = "IBM System x3800",
	31	+ .matches = {
	32	+ DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
	33	+ DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
	34	+ },
	35	+ },
	36	+ {}
	37	+};
	38	+
	39	+void __init pci_acpi_crs_quirks(void)
	40	+{
	41	+ int year;
	42	+
	43	+ if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
	44	+ pci_use_crs = false;
	45	+
	46	+ dmi_check_system(pci_use_crs_table);
	47	+
	48	+ /*
	49	+ * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
	50	+ * takes precedence over anything we figured out above.
	51	+ */
	52	+ if (pci_probe & PCI_ROOT_NO_CRS)
	53	+ pci_use_crs = false;
	54	+ else if (pci_probe & PCI_USE__CRS)
	55	+ pci_use_crs = true;
	56	+
	57	+ printk(KERN_INFO "PCI: %s host bridge windows from ACPI; "
	58	+ "if necessary, use \"pci=%s\" and report a bug\n",
	59	+ pci_use_crs ? "Using" : "Ignoring",
	60	+ pci_use_crs ? "nocrs" : "use_crs");
	61	+}
	62	+
18	63	static acpi_status
19	64	resource_to_addr(struct acpi_resource *resource,
20	65	struct acpi_resource_address64 *addr)
...	...	@@ -106,7 +151,7 @@
106	151	res->child = NULL;
107	152	align_resource(info->bridge, res);
108	153
109		- if (!(pci_probe & PCI_USE__CRS)) {
	154	+ if (!pci_use_crs) {
110	155	dev_printk(KERN_DEBUG, &info->bridge->dev,
111	156	"host bridge window %pR (ignored)\n", res);
112	157	return AE_OK;
113	158
...	...	@@ -137,12 +182,8 @@
137	182	struct pci_root_info info;
138	183	size_t size;
139	184
140		- if (pci_probe & PCI_USE__CRS)
	185	+ if (pci_use_crs)
141	186	pci_bus_remove_resources(bus);
142		- else
143		- dev_info(&device->dev,
144		- "ignoring host bridge windows from ACPI; "
145		- "boot with \"pci=use_crs\" to use them\n");
146	187
147	188	info.bridge = device;
148	189	info.bus = bus;
...	...	@@ -520,6 +520,9 @@
520	520	} else if (!strcmp(str, "use_crs")) {
521	521	pci_probe \|= PCI_USE__CRS;
522	522	return NULL;
	523	+ } else if (!strcmp(str, "nocrs")) {
	524	+ pci_probe \|= PCI_ROOT_NO_CRS;
	525	+ return NULL;
523	526	} else if (!strcmp(str, "earlydump")) {
524	527	pci_early_dump_regs = 1;
525	528	return NULL;
...	...	@@ -566,6 +566,7 @@
566	566	if (acpi_pci_disabled)
567	567	return 0;
568	568
	569	+ pci_acpi_crs_quirks();
569	570	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
570	571	return -ENODEV;
571	572
...	...	@@ -104,6 +104,7 @@
104	104
105	105	struct pci_bus pci_acpi_scan_root(struct acpi_device device, int domain,
106	106	int bus);
	107	+void pci_acpi_crs_quirks(void);
107	108
108	109	/* --------------------------------------------------------------------------
109	110	Processor