From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- Documentation/x86/x86_64/uefi.rst | 58 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 Documentation/x86/x86_64/uefi.rst (limited to 'Documentation/x86/x86_64/uefi.rst') diff --git a/Documentation/x86/x86_64/uefi.rst b/Documentation/x86/x86_64/uefi.rst new file mode 100644 index 000000000..fbc30c9a0 --- /dev/null +++ b/Documentation/x86/x86_64/uefi.rst @@ -0,0 +1,58 @@ +.. SPDX-License-Identifier: GPL-2.0 + +===================================== +General note on [U]EFI x86_64 support +===================================== + +The nomenclature EFI and UEFI are used interchangeably in this document. + +Although the tools below are _not_ needed for building the kernel, +the needed bootloader support and associated tools for x86_64 platforms +with EFI firmware and specifications are listed below. + +1. UEFI specification: http://www.uefi.org + +2. Booting Linux kernel on UEFI x86_64 platform requires bootloader + support. Elilo with x86_64 support can be used. + +3. x86_64 platform with EFI/UEFI firmware. + +Mechanics +--------- + +- Build the kernel with the following configuration:: + + CONFIG_FB_EFI=y + CONFIG_FRAMEBUFFER_CONSOLE=y + + If EFI runtime services are expected, the following configuration should + be selected:: + + CONFIG_EFI=y + CONFIG_EFIVAR_FS=y or m # optional + +- Create a VFAT partition on the disk +- Copy the following to the VFAT partition: + + elilo bootloader with x86_64 support, elilo configuration file, + kernel image built in first step and corresponding + initrd. Instructions on building elilo and its dependencies + can be found in the elilo sourceforge project. + +- Boot to EFI shell and invoke elilo choosing the kernel image built + in first step. +- If some or all EFI runtime services don't work, you can try following + kernel command line parameters to turn off some or all EFI runtime + services. + + noefi + turn off all EFI runtime services + reboot_type=k + turn off EFI reboot runtime service + +- If the EFI memory map has additional entries not in the E820 map, + you can include those entries in the kernels memory map of available + physical RAM by using the following kernel command line parameter. + + add_efi_memmap + include EFI memory map of available physical RAM -- cgit v1.2.3