This series (on top of efi/next) adds a basic printf implementation for the EFI stub to use. Patches 1-2 are minor cleanup. Patch 3 adds an on-stack buffer for efi_puts to do the char to UTF-16 conversion, to avoid calling into the firmware for each character. Patches 4-16 copy the simple printf implementation from arch/x86/boot/printf.c and spruce it up. The main enhancements are support for 64-bit integers and conversion to vsnprintf. There are small fixes to correct the behavior for edge cases (detailed in the individual patches). Patch 17 changes efi_info/efi_err to actually use efi_printk, and introduces a loglevel into the EFI stub instead of just quiet/non-quiet. The loglevels are reused from the main kernel. An efi_debug macro is also added, but is currently unused. As an aside, we chose efi_info over efi_pr_info, but I'm wondering whether we should make it efi_pr_info after all: there is already an efi_info symbol (structure type and field name) so it might lead to some confusion. Patch 18-19 add an option to list the available modes from the GOP, which should make using the new video=efifb parameters easier. Patches 20-24 incorporate UTF-16 support into the new printf function and use it in a couple of places. Arvind Sankar (24): efi/libstub: Include dependencies of efistub.h efi/libstub: Rename efi_[char16_]printk to efi_[char16_]puts efi/libstub: Buffer output of efi_puts efi/libstub: Add a basic printf implementation efi/libstub: Optimize for size instead of speed efi/printf: Drop %n format and L qualifier efi/printf: Add 64-bit and 8-bit integer support efi/printf: Factor out flags parsing and handle '%' earlier efi/printf: Fix minor bug in precision handling efi/printf: Merge 'p' with the integer formats efi/printf: Factor out width/precision parsing efi/printf: Factor out integer argument retrieval efi/printf: Handle null string input efi/printf: Refactor code to consolidate padding and output efi/printf: Abort on invalid format efi/printf: Turn vsprintf into vsnprintf efi/libstub: Implement printk-style logging efi/libstub: Add definitions for console input and events efi/gop: Add an option to list out the available GOP modes efi/printf: Add support for wchar_t (UTF-16) efi/libstub: Add UTF-8 decoding to efi_puts efi/libstub: Use %ls for filename efi/libstub: Get the exact UTF-8 length efi/libstub: Use snprintf with %ls to convert the command line Documentation/fb/efifb.rst | 5 + arch/x86/include/asm/efi.h | 10 + arch/x86/xen/efi.c | 2 +- drivers/firmware/efi/libstub/Makefile | 6 +- .../firmware/efi/libstub/efi-stub-helper.c | 275 ++++++--- drivers/firmware/efi/libstub/efistub.h | 107 +++- drivers/firmware/efi/libstub/file.c | 4 +- drivers/firmware/efi/libstub/gop.c | 97 ++- drivers/firmware/efi/libstub/vsprintf.c | 563 ++++++++++++++++++ include/linux/efi.h | 4 +- 10 files changed, 968 insertions(+), 105 deletions(-) create mode 100644 drivers/firmware/efi/libstub/vsprintf.c -- 2.26.2
