From 613cd0c46796cae340382679bc01ef220daf3768 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Wed, 29 Dec 2021 11:57:36 -0700 Subject: efi: Locate all block devices in the app When starting the app, locate all block devices and make them available to U-Boot. This allows listing partitions and accessing files in filesystems. EFI also has the concept of 'disks', meaning boot media. For now, this is not obviously useful in U-Boot, but add code to at least locate these. This can be expanded later as needed. We cannot use printf() in the early stub or app since it is not compiled in Signed-off-by: Simon Glass Reviewed-by: Heinrich Schuchardt --- doc/develop/uefi/u-boot_on_efi.rst | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'doc/develop') diff --git a/doc/develop/uefi/u-boot_on_efi.rst b/doc/develop/uefi/u-boot_on_efi.rst index 5f2f850f071..8f81b799072 100644 --- a/doc/develop/uefi/u-boot_on_efi.rst +++ b/doc/develop/uefi/u-boot_on_efi.rst @@ -265,9 +265,7 @@ This work could be extended in a number of ways: - Figure out how to solve the interrupt problem -- Add more drivers to the application side (e.g. block devices, USB, - environment access). This would mostly be an academic exercise as a strong - use case is not readily apparent, but it might be fun. +- Add more drivers to the application side (e.g.USB, environment access). - Avoid turning off boot services in the stub. Instead allow U-Boot to make use of boot services in case it wants to. It is unclear what it might want -- cgit v1.3.1 From 6e7ad4a45f6e2b036fc56942293b8471ece3341d Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Wed, 29 Dec 2021 11:57:38 -0700 Subject: x86: Allow booting a kernel from the EFI app At present this is disabled, but it should work so long as the kernel does not need EFI services. Enable it and add a note about remaining work. Signed-off-by: Simon Glass --- arch/x86/lib/bootm.c | 11 +++++++---- doc/develop/uefi/u-boot_on_efi.rst | 2 +- 2 files changed, 8 insertions(+), 5 deletions(-) (limited to 'doc/develop') diff --git a/arch/x86/lib/bootm.c b/arch/x86/lib/bootm.c index 667e5e689e3..57cba5c65d3 100644 --- a/arch/x86/lib/bootm.c +++ b/arch/x86/lib/bootm.c @@ -179,10 +179,14 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit) * U-Boot is setting them up that way for itself in * arch/i386/cpu/cpu.c. * - * Note that we cannot currently boot a kernel while running as - * an EFI application. Please use the payload option for that. + * Note: this is incomplete for EFI kernels! + * + * This can boot a kernel while running as an EFI application, + * but if the kernel requires EFI support then that support needs + * to be enabled first (see EFI_LOADER). Also the EFI information + * must enabled with setup_efi_info(). See setup_zimage() for + * how this is done with the stub. */ -#ifndef CONFIG_EFI_APP __asm__ __volatile__ ( "movl $0, %%ebp\n" "cli\n" @@ -191,7 +195,6 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit) [boot_params] "S"(setup_base), "b"(0), "D"(0) ); -#endif } /* We can't get to here */ diff --git a/doc/develop/uefi/u-boot_on_efi.rst b/doc/develop/uefi/u-boot_on_efi.rst index 8f81b799072..acad6397e81 100644 --- a/doc/develop/uefi/u-boot_on_efi.rst +++ b/doc/develop/uefi/u-boot_on_efi.rst @@ -269,7 +269,7 @@ This work could be extended in a number of ways: - Avoid turning off boot services in the stub. Instead allow U-Boot to make use of boot services in case it wants to. It is unclear what it might want - though. + though. It is better to use the app. Where is the code? ------------------ -- cgit v1.3.1