[PATCH] mmconfig: Reject a broken MCFG tables on Asus etc

This rejects broken MCFG tables on Asus. When the table
looks bogus just disable mmconfig

Arjan and Andi suggested this.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>

arch/i386/pci/mmconfig-shared.c

@@ -197,6 +197,26 @@ static __init void pci_mmcfg_insert_resources(void)
 	}
 }
 
+static void __init pci_mmcfg_reject_broken(void)
+{
+	typeof(pci_mmcfg_config[0]) *cfg = &pci_mmcfg_config[0];
+
+	/*
+	 * Handle more broken MCFG tables on Asus etc.
+	 * They only contain a single entry for bus 0-0.
+	 */
+	if (pci_mmcfg_config_num == 1 &&
+	    cfg->pci_segment == 0 &&
+	    (cfg->start_bus_number | cfg->end_bus_number) == 0) {
+		kfree(pci_mmcfg_config);
+		pci_mmcfg_config = NULL;
+		pci_mmcfg_config_num = 0;
+
+		printk(KERN_ERR "PCI: start and end of bus number is 0. "
+		       "Rejected as broken MCFG.");
+	}
+}
+
 void __init pci_mmcfg_init(int type)
 {
 	int known_bridge = 0;
@@ -207,8 +227,10 @@ void __init pci_mmcfg_init(int type)
 	if (type == 1 && pci_mmcfg_check_hostbridge())
 		known_bridge = 1;
 
-	if (!known_bridge)
+	if (!known_bridge) {
 		acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
+		pci_mmcfg_reject_broken();
+	}
 
 	if ((pci_mmcfg_config_num == 0) ||
 	    (pci_mmcfg_config == NULL) ||

arch/i386/pci/mmconfig.c

@@ -47,15 +47,6 @@ static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn)
 			return cfg->address;
 	}
 
-	/* Handle more broken MCFG tables on Asus etc.
-	   They only contain a single entry for bus 0-0. Assume
- 	   this applies to all busses. */
-	cfg = &pci_mmcfg_config[0];
-	if (pci_mmcfg_config_num == 1 &&
-		cfg->pci_segment == 0 &&
-		(cfg->start_bus_number | cfg->end_bus_number) == 0)
-		return cfg->address;
-
 	/* Fall back to type 0 */
 	return 0;
 }

arch/x86_64/pci/mmconfig.c

@@ -28,39 +28,6 @@ struct mmcfg_virt {
 };
 static struct mmcfg_virt *pci_mmcfg_virt;
 
-static inline int mcfg_broken(void)
-{
-	struct acpi_mcfg_allocation *cfg = &pci_mmcfg_config[0];
-
-	/* Handle more broken MCFG tables on Asus etc.
-	   They only contain a single entry for bus 0-0. Assume
- 	   this applies to all busses. */
-	if (pci_mmcfg_config_num == 1 &&
-	    cfg->pci_segment_group_number == 0 &&
-	    (cfg->start_bus_number | cfg->end_bus_number) == 0)
-		return 1;
-	return 0;
-}
-
-static void __iomem *mcfg_ioremap(struct acpi_mcfg_allocation *cfg)
-{
-	void __iomem *addr;
-	u32 size;
-
-	if (mcfg_broken())
-		size = 256 << 20;
-	else
-		size = (cfg->end_bus_number + 1) << 20;
-
-	addr = ioremap_nocache(cfg->base_address, size);
-	if (addr) {
-		printk(KERN_INFO "PCI: Using MMCONFIG at %x - %x\n",
-		       cfg->base_address,
-		       cfg->base_address + size - 1);
-	}
-	return addr;
-}
-
 static char __iomem *get_virt(unsigned int seg, unsigned bus)
 {
 	int cfg_num = -1;
@@ -78,9 +45,6 @@ static char __iomem *get_virt(unsigned int seg, unsigned bus)
 			return pci_mmcfg_virt[cfg_num].virt;
 	}
 
-	if (mcfg_broken())
-		return pci_mmcfg_virt[0].virt;
-
 	/* Fall back to type 0 */
 	return NULL;
 }
@@ -160,6 +124,20 @@ static struct pci_raw_ops pci_mmcfg = {
 	.write =	pci_mmcfg_write,
 };
 
+static void __iomem * __init mcfg_ioremap(struct acpi_mcfg_allocation *cfg)
+{
+	void __iomem *addr;
+	u32 size;
+
+	size = (cfg->end_bus_number + 1) << 20;
+	addr = ioremap_nocache(cfg->address, size);
+	if (addr) {
+		printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n",
+		       cfg->address, cfg->address + size - 1);
+	}
+	return addr;
+}
+
 int __init pci_mmcfg_arch_init(void)
 {
 	int i;