[v4,0/4] x86/boot: Reduce assembly code

Message

Frediano Ziglio Sept. 25, 2024, 6 a.m. UTC

This series came from part of the work of removing duplications between
boot code and rewriting part of code from assembly to C.
First 2 patches rework BIOS/PVH paths to reuse some code.
Third patch rewrites EFI code in pure C.

Changes since v1, more details in specific commits:
- style updates;
- comments and descriptions improvements;
- other improvements.

Changes since v2:
- rebased on master, resolved conflicts;
- add comment on trampoline section.

Changes since v3:
- changed new function name;
- declare efi_multiboot2 in a separate header;
- distinguish entry point from using magic number;
- other minor changes (see commens in commits).

Frediano Ziglio (4):
  x86/boot: Initialise BSS sooner
  x86/boot: Refactor BIOS/PVH start
  x86/boot: Rewrite EFI/MBI2 code partly in C
  x86/boot: Improve MBI2 structure check

 xen/arch/x86/boot/head.S       | 287 ++++++++++-----------------------
 xen/arch/x86/efi/Makefile      |   1 +
 xen/arch/x86/efi/efi-boot.h    |   6 +-
 xen/arch/x86/efi/parse-mbi2.c  |  59 +++++++
 xen/arch/x86/efi/stub.c        |   3 +-
 xen/arch/x86/include/asm/efi.h |  18 +++
 6 files changed, 170 insertions(+), 204 deletions(-)
 create mode 100644 xen/arch/x86/efi/parse-mbi2.c
 create mode 100644 xen/arch/x86/include/asm/efi.h