i386: insert unclaimed MMCONFIG resources

Insert the unclaimed MMCONFIG resources into the resource tree without the IORESOURCE_BUSY flag during late initialization. This allows the MMCONFIG regions to be visible in the iomem resource tree without interfering with other system resources that were discovered during PCI initialization. [akpm@linux-foundation.org: nanofixes] Signed-off-by: Aaron Durbin <adurbin@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

i386: insert unclaimed MMCONFIG resources
Insert the unclaimed MMCONFIG resources into the resource tree without the IORESOURCE_BUSY flag during late initialization. This allows the MMCONFIG regions to be visible in the iomem resource tree without interfering with other system resources that were discovered during PCI initialization. [akpm@linux-foundation.org: nanofixes] Signed-off-by: Aaron Durbin <adurbin@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aaron Durbin · Linus Torvalds
1 parent 08705b89ec
Showing 1 changed file with 45 additions and 3 deletions Side-by-side Diff
arch/i386/pci/mmconfig-shared.c
@@ -24,6 +24,9 @@
  
 DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS);
  
+/* Indicate if the mmcfg resources have been placed into the resource table. */
+static int __initdata pci_mmcfg_resources_inserted;
+
 /* K8 systems have some devices (typically in the builtin northbridge)
    that are only accessible using type1
    Normally this can be expressed in the MCFG by not listing them
@@ -170,7 +173,7 @@
 	return name != NULL;
 }
  
-static void __init pci_mmcfg_insert_resources(void)
+static void __init pci_mmcfg_insert_resources(unsigned long resource_flags)
 {
 #define PCI_MMCFG_RESOURCE_NAME_LEN 19
 	int i;
  
@@ -194,10 +197,13 @@
 			 cfg->pci_segment);
 		res->start = cfg->address;
 		res->end = res->start + (num_buses << 20) - 1;
-		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+		res->flags = IORESOURCE_MEM | resource_flags;
 		insert_resource(&iomem_resource, res);
 		names += PCI_MMCFG_RESOURCE_NAME_LEN;
 	}
+
+	/* Mark that the resources have been inserted. */
+	pci_mmcfg_resources_inserted = 1;
 }
  
 static void __init pci_mmcfg_reject_broken(int type)
  
  
@@ -267,8 +273,44 @@
 		if (type == 1)
 			unreachable_devices();
 		if (known_bridge)
-			pci_mmcfg_insert_resources();
+			pci_mmcfg_insert_resources(IORESOURCE_BUSY);
 		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
+	} else {
+		/*
+		 * Signal not to attempt to insert mmcfg resources because
+		 * the architecture mmcfg setup could not initialize.
+		 */
+		pci_mmcfg_resources_inserted = 1;
 	}
 }
+
+static int __init pci_mmcfg_late_insert_resources(void)
+{
+	/*
+	 * If resources are already inserted or we are not using MMCONFIG,
+	 * don't insert the resources.
+	 */
+	if ((pci_mmcfg_resources_inserted == 1) ||
+	    (pci_probe & PCI_PROBE_MMCONF) == 0 ||
+	    (pci_mmcfg_config_num == 0) ||
+	    (pci_mmcfg_config == NULL) ||
+	    (pci_mmcfg_config[0].address == 0))
+		return 1;
+
+	/*
+	 * Attempt to insert the mmcfg resources but not with the busy flag
+	 * marked so it won't cause request errors when __request_region is
+	 * called.
+	 */
+	pci_mmcfg_insert_resources(0);
+
+	return 0;
+}
+
+/*
+ * Perform MMCONFIG resource insertion after PCI initialization to allow for
+ * misprogrammed MCFG tables that state larger sizes but actually conflict
+ * with other system resources.
+ */
+late_initcall(pci_mmcfg_late_insert_resources);
...	...	@@ -24,6 +24,9 @@
24	24
25	25	DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS);
26	26
	27	+/* Indicate if the mmcfg resources have been placed into the resource table. */
	28	+static int __initdata pci_mmcfg_resources_inserted;
	29	+
27	30	/* K8 systems have some devices (typically in the builtin northbridge)
28	31	that are only accessible using type1
29	32	Normally this can be expressed in the MCFG by not listing them
...	...	@@ -170,7 +173,7 @@
170	173	return name != NULL;
171	174	}
172	175
173		-static void __init pci_mmcfg_insert_resources(void)
	176	+static void __init pci_mmcfg_insert_resources(unsigned long resource_flags)
174	177	{
175	178	#define PCI_MMCFG_RESOURCE_NAME_LEN 19
176	179	int i;
177	180
...	...	@@ -194,10 +197,13 @@
194	197	cfg->pci_segment);
195	198	res->start = cfg->address;
196	199	res->end = res->start + (num_buses << 20) - 1;
197		- res->flags = IORESOURCE_MEM \| IORESOURCE_BUSY;
	200	+ res->flags = IORESOURCE_MEM \| resource_flags;
198	201	insert_resource(&iomem_resource, res);
199	202	names += PCI_MMCFG_RESOURCE_NAME_LEN;
200	203	}
	204	+
	205	+ /* Mark that the resources have been inserted. */
	206	+ pci_mmcfg_resources_inserted = 1;
201	207	}
202	208
203	209	static void __init pci_mmcfg_reject_broken(int type)
204	210
205	211
...	...	@@ -267,8 +273,44 @@
267	273	if (type == 1)
268	274	unreachable_devices();
269	275	if (known_bridge)
270		- pci_mmcfg_insert_resources();
	276	+ pci_mmcfg_insert_resources(IORESOURCE_BUSY);
271	277	pci_probe = (pci_probe & ~PCI_PROBE_MASK) \| PCI_PROBE_MMCONF;
	278	+ } else {
	279	+ /*
	280	+ * Signal not to attempt to insert mmcfg resources because
	281	+ * the architecture mmcfg setup could not initialize.
	282	+ */
	283	+ pci_mmcfg_resources_inserted = 1;
272	284	}
273	285	}
	286	+
	287	+static int __init pci_mmcfg_late_insert_resources(void)
	288	+{
	289	+ /*
	290	+ * If resources are already inserted or we are not using MMCONFIG,
	291	+ * don't insert the resources.
	292	+ */
	293	+ if ((pci_mmcfg_resources_inserted == 1) \|\|
	294	+ (pci_probe & PCI_PROBE_MMCONF) == 0 \|\|
	295	+ (pci_mmcfg_config_num == 0) \|\|
	296	+ (pci_mmcfg_config == NULL) \|\|
	297	+ (pci_mmcfg_config[0].address == 0))
	298	+ return 1;
	299	+
	300	+ /*
	301	+ * Attempt to insert the mmcfg resources but not with the busy flag
	302	+ * marked so it won't cause request errors when __request_region is
	303	+ * called.
	304	+ */
	305	+ pci_mmcfg_insert_resources(0);
	306	+
	307	+ return 0;
	308	+}
	309	+
	310	+/*
	311	+ * Perform MMCONFIG resource insertion after PCI initialization to allow for
	312	+ * misprogrammed MCFG tables that state larger sizes but actually conflict
	313	+ * with other system resources.
	314	+ */
	315	+late_initcall(pci_mmcfg_late_insert_resources);