From a0998eb15afeffbf52a2c2829318f67df9ac57b8 Mon Sep 17 00:00:00 2001 From: Dave Young Date: Fri, 20 Dec 2013 18:02:17 +0800 Subject: efi: Export more EFI table variables to sysfs Export fw_vendor, runtime and config table physical addresses to /sys/firmware/efi/{fw_vendor,runtime,config_table} because kexec kernels need them. From EFI spec these 3 variables will be updated to virtual address after entering virtual mode. But kernel startup code will need the physical address. Signed-off-by: Dave Young Tested-by: Toshi Kani Signed-off-by: Matt Fleming --- drivers/firmware/efi/efi.c | 41 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 2e2fbdec0845..72533af72b98 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -32,6 +32,9 @@ struct efi __read_mostly efi = { .hcdp = EFI_INVALID_TABLE_ADDR, .uga = EFI_INVALID_TABLE_ADDR, .uv_systab = EFI_INVALID_TABLE_ADDR, + .fw_vendor = EFI_INVALID_TABLE_ADDR, + .runtime = EFI_INVALID_TABLE_ADDR, + .config_table = EFI_INVALID_TABLE_ADDR, }; EXPORT_SYMBOL(efi); @@ -71,13 +74,49 @@ static ssize_t systab_show(struct kobject *kobj, static struct kobj_attribute efi_attr_systab = __ATTR(systab, 0400, systab_show, NULL); +#define EFI_FIELD(var) efi.var + +#define EFI_ATTR_SHOW(name) \ +static ssize_t name##_show(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf) \ +{ \ + return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \ +} + +EFI_ATTR_SHOW(fw_vendor); +EFI_ATTR_SHOW(runtime); +EFI_ATTR_SHOW(config_table); + +static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor); +static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime); +static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table); + static struct attribute *efi_subsys_attrs[] = { &efi_attr_systab.attr, - NULL, /* maybe more in the future? */ + &efi_attr_fw_vendor.attr, + &efi_attr_runtime.attr, + &efi_attr_config_table.attr, + NULL, }; +static umode_t efi_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + umode_t mode = attr->mode; + + if (attr == &efi_attr_fw_vendor.attr) + return (efi.fw_vendor == EFI_INVALID_TABLE_ADDR) ? 0 : mode; + else if (attr == &efi_attr_runtime.attr) + return (efi.runtime == EFI_INVALID_TABLE_ADDR) ? 0 : mode; + else if (attr == &efi_attr_config_table.attr) + return (efi.config_table == EFI_INVALID_TABLE_ADDR) ? 0 : mode; + + return mode; +} + static struct attribute_group efi_subsys_attr_group = { .attrs = efi_subsys_attrs, + .is_visible = efi_attr_is_visible, }; static struct efivars generic_efivars; -- cgit v1.2.3