Fork of ipxe; additional commands and features https://git.openslx.org/openslx-ng/ipxe.git/atom/src/arch/i386/scripts/efi.lds?h=openslx 2009-01-07T22:59:05+00:00 2009-01-07T22:59:05+00:00 Michael Brown 2009-01-07T02:05:51+00:00 urn:sha1:314779eb369db746be5373b398111d5b746d67de elf2efi converts a suitable ELF executable (containing relocation information, and with appropriate virtual addresses) into an EFI executable. It is less tightly coupled with the gPXE build process and, in particular, does not require the use of a hand-crafted PE image header in efiprefix.S. elf2efi correctly handles .bss sections, which significantly reduces the size of the gPXE EFI executable. 2008-11-18T03:46:27+00:00 Michael Brown 2008-11-18T03:46:27+00:00 urn:sha1:c661945e82b939a942b23a40d9d23b15ec771503 2008-10-17T02:12:11+00:00 Michael Brown 2008-10-17T02:12:11+00:00 urn:sha1:7982e79d3cc29489cfb3dbbf574ba23e9d5500c7 The section name seems to have significance for some versions of binutils. There is no way to instruct gcc that sections such as .bss16 contain uninitialised data; it will emit them with contents explicitly set to zero. We therefore have to rely on the linker script to force these sections to become uninitialised-data sections. We do this by marking them as NOLOAD; this seems to be the closest semantic equivalent in the linker script language. However, this gets ignored by some versions of ld (including 2.17 as shipped with Debian Etch), which mark the resulting sections with (CONTENTS,ALLOC,LOAD,DATA). Combined with the fact that this version of ld seems to ignore the specified LMA for these sections, this means that they end up overlapping other sections, and so parts of .prefix (for example) get obliterated by .data16's bss section. Rename the .bss sections from .section_bss to .bss.section; this seems to cause these versions of ld to treat them as uninitialised data. 2008-10-13T09:41:38+00:00 Michael Brown 2008-10-13T09:41:38+00:00 urn:sha1:64e5ca0582a54078e789ae36f5b62e0034503323 Some versions of ld choke on the "AT ( _xxx_lma )" in efi.lds with an error saying "nonconstant expression for load base". Since these were only explicitly setting the LMA to the address that it would have had anyway, they can be safely omitted. 2008-10-13T09:24:14+00:00 Michael Brown 2008-10-12T00:55:55+00:00 urn:sha1:81d92c6d34f9ce68f7c2bbd5b92352b3a631bcd0 We have EFI APIs for CPU I/O, PCI I/O, timers, console I/O, user access and user memory allocation. EFI executables are created using the vanilla GNU toolchain, with the EXE header handcrafted in assembly and relocations generated by a custom efilink utility.