On Tue, 08 Jul, at 11:00:58AM, Lee, Chun-Yi wrote: > The original patch is from Ben Hutchings's contribution to debian > kernel. Got Ben's permission to remove the code of efi-pstore.c and > then patch to linux-efi: > https://github.com/BlankOn/linux-debian/blob/master/debian/patches/features/all/efi-autoload-efivars.patch > > efivars is generally useful to have on EFI systems, and in some cases > it may be impossible to load it after a kernel upgrade in order to > complete a boot loader update. At the same time we don't want to waste > memory on non-EFI systems by making them built-in. > > Instead, give them module aliases as if they are platform drivers, and > register a corresponding platform device whenever EFI runtime services > are available. This should trigger udev to load them. > > Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx> > Cc: Matt Fleming <matt.fleming@xxxxxxxxx> > Signed-off-by: Lee, Chun-Yi <jlee@xxxxxxxx> > --- > arch/x86/platform/efi/efi.c | 15 +++++++++++++++ > drivers/firmware/efi/efivars.c | 1 + > 2 files changed, 16 insertions(+) > > diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c > index 87fc96b..c295c08 100644 > --- a/arch/x86/platform/efi/efi.c > +++ b/arch/x86/platform/efi/efi.c > @@ -44,6 +44,7 @@ > #include <linux/io.h> > #include <linux/reboot.h> > #include <linux/bcd.h> > +#include <linux/platform_device.h> > > #include <asm/setup.h> > #include <asm/efi.h> > @@ -780,6 +781,20 @@ void __init efi_late_init(void) > efi_bgrt_init(); > } > > +#ifdef CONFIG_EFI_VARS_MODULE > +static int __init efi_load_efivars(void) > +{ > + struct platform_device *pdev; > + > + if (!efi_enabled(EFI_RUNTIME_SERVICES)) > + return 0; > + > + pdev = platform_device_register_simple("efivars", 0, NULL, 0); > + return IS_ERR(pdev) ? PTR_ERR(pdev) : 0; > +} > +device_initcall(efi_load_efivars); > +#endif > + Could this be moved to drivers/firmware/efi/efi.c? That way the arm64 folks could benefit from it too. > void __init efi_set_executable(efi_memory_desc_t *md, bool executable) > { > u64 addr, npages; > diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c > index 463c565..f256ecd 100644 > --- a/drivers/firmware/efi/efivars.c > +++ b/drivers/firmware/efi/efivars.c > @@ -78,6 +78,7 @@ MODULE_AUTHOR("Matt Domsch <Matt_Domsch@xxxxxxxx>"); > MODULE_DESCRIPTION("sysfs interface to EFI Variables"); > MODULE_LICENSE("GPL"); > MODULE_VERSION(EFIVARS_VERSION); > +MODULE_ALIAS("platform:efivars"); > > LIST_HEAD(efivar_sysfs_list); > EXPORT_SYMBOL_GPL(efivar_sysfs_list); > -- > 1.8.4.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-efi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Matt Fleming, Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
