Hi Yinghai, >> +int arch_acpi_pci_root_remove(struct acpi_pci_root *root) >> +{ >> + acpi_status status; >> + unsigned long long base_addr; >> + >> + /* Remove MMCFG information for host bridges with _CBA method */ >> + status = acpi_evaluate_integer(root->device->handle, METHOD_NAME__CBA, >> + NULL, &base_addr); > > add one flag in acpi_pci_root about we added mmconf for it before? > like mmconf_added? > I feel adding a flag here doesn't help here. For any hot-pluggable PCI host bridge with _CBA method available, arch_acpi_pci_root_remove() should delete the MMCFG information, no matter it's added by __pci_mmcfg_init() or arch_acpi_pci_root_add(). So check existence of _CBA seems simpler here. Thanks! On 04/09/2012 03:19 AM, Yinghai Lu wrote: > On Sun, Apr 8, 2012 at 10:12 AM, Jiang Liu <liuj97@xxxxxxxxx> wrote: >> This patch enhances pci_root driver to update MMCFG information when >> hot-plugging PCI root bridges on x86 platforms. >> >> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx> >> --- >> arch/x86/pci/acpi.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++ >> drivers/acpi/pci_root.c | 20 ++++++++++++++++ >> include/acpi/acnames.h | 1 + >> include/linux/pci-acpi.h | 3 ++ >> 4 files changed, 82 insertions(+), 0 deletions(-) >> >> diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c >> index da0149d..9184970 100644 >> --- a/arch/x86/pci/acpi.c >> +++ b/arch/x86/pci/acpi.c >> @@ -488,6 +488,64 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root) >> return bus; >> } >> >> +int arch_acpi_pci_root_add(struct acpi_pci_root *root) >> +{ >> + int result = 0; >> + acpi_status status; >> + unsigned long long base_addr; >> + struct pci_mmcfg_region *cfg; >> + >> + /* >> + * Try to insert MMCFG information for host bridges with _CBA method >> + */ >> + status = acpi_evaluate_integer(root->device->handle, METHOD_NAME__CBA, >> + NULL, &base_addr); >> + if (ACPI_SUCCESS(status)) { >> + result = pci_mmconfig_insert(root->segment, >> + root->secondary.start, >> + root->secondary.end, >> + base_addr); >> + /* >> + * MMCFG information for hot-pluggable host bridges may have >> + * already been added by __pci_mmcfg_init(); >> + */ >> + if (result == -EEXIST) >> + result = 0; >> + } else if (status == AE_NOT_FOUND) { >> + /* >> + * Check whether MMCFG information has been added for >> + * host bridges without _CBA method. >> + */ >> + rcu_read_lock(); >> + cfg = pci_mmconfig_lookup(root->segment, root->secondary.start); >> + if (!cfg || cfg->end_bus < root->secondary.end) >> + result = -ENODEV; >> + rcu_read_unlock(); >> + } else >> + result = -ENODEV; >> + >> + return result; >> +} >> + >> +int arch_acpi_pci_root_remove(struct acpi_pci_root *root) >> +{ >> + acpi_status status; >> + unsigned long long base_addr; >> + >> + /* Remove MMCFG information for host bridges with _CBA method */ >> + status = acpi_evaluate_integer(root->device->handle, METHOD_NAME__CBA, >> + NULL, &base_addr); > > add one flag in acpi_pci_root about we added mmconf for it before? > like mmconf_added? > >> + if (ACPI_SUCCESS(status)) >> + return pci_mmconfig_delete(root->segment, >> + root->secondary.start, >> + root->secondary.end, >> + base_addr); >> + else if (status != AE_NOT_FOUND) >> + return -ENODEV; >> + >> + return 0; >> +} >> + >> int __init pci_acpi_init(void) >> { >> struct pci_dev *dev = NULL; >> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c >> index 4a7d575..a62bfa8 100644 >> --- a/drivers/acpi/pci_root.c >> +++ b/drivers/acpi/pci_root.c >> @@ -448,6 +448,16 @@ out: >> } >> EXPORT_SYMBOL(acpi_pci_osc_control_set); >> >> +int __weak arch_acpi_pci_root_add(struct acpi_pci_root *root) >> +{ >> + return 0; >> +} >> + >> +int __weak arch_acpi_pci_root_remove(struct acpi_pci_root *root) >> +{ >> + return 0; >> +} >> + >> static int __devinit acpi_pci_root_add(struct acpi_device *device) >> { >> unsigned long long segment, bus; >> @@ -504,6 +514,14 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device) >> strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS); >> device->driver_data = root; >> >> + if (arch_acpi_pci_root_add(root)) { >> + printk(KERN_ERR PREFIX >> + "can't add MMCFG information for Bus %04x:%02x\n", >> + root->segment, (unsigned int)root->secondary.start); >> + result = -ENODEV; >> + goto out_free; >> + } >> + >> /* >> * All supported architectures that use ACPI have support for >> * PCI domains, so we indicate this in _OSC support capabilities. >> @@ -629,6 +647,7 @@ out_del_root: >> list_del_rcu(&root->node); >> mutex_unlock(&acpi_pci_root_lock); >> synchronize_rcu(); >> + arch_acpi_pci_root_remove(root); >> out_free: >> kfree(root); >> return result; >> @@ -679,6 +698,7 @@ out: >> list_del_rcu(&root->node); >> mutex_unlock(&acpi_pci_root_lock); >> synchronize_rcu(); >> + arch_acpi_pci_root_remove(root); >> kfree(root); >> >> return 0; >> diff --git a/include/acpi/acnames.h b/include/acpi/acnames.h >> index 38f5088..99bda75 100644 >> --- a/include/acpi/acnames.h >> +++ b/include/acpi/acnames.h >> @@ -62,6 +62,7 @@ >> #define METHOD_NAME__AEI "_AEI" >> #define METHOD_NAME__PRW "_PRW" >> #define METHOD_NAME__SRS "_SRS" >> +#define METHOD_NAME__CBA "_CBA" >> >> /* Method names - these methods must appear at the namespace root */ >> >> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h >> index ac93634..816b971 100644 >> --- a/include/linux/pci-acpi.h >> +++ b/include/linux/pci-acpi.h >> @@ -38,6 +38,9 @@ static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus) >> >> void acpi_pci_root_rescan(void); >> >> +extern int arch_acpi_pci_root_add(struct acpi_pci_root *root); >> +extern int arch_acpi_pci_root_remove(struct acpi_pci_root *root); >> + > > don't need extern here. > >> #else >> >> static inline void acpi_pci_root_rescan(void) { } >> -- >> 1.7.5.4 >> -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html