[i386] Add explicit ""aw", @nobits" declarations to stack sections
As reported by Stefan, commit 13d09e6 ("[i386] Simplify linker script
and standardise linker-defined symbol names") breaks gdb, readelf and
associated utilities.
This is caused by the .stack section overwriting a block in the middle
of the .debug_info section (despite being included in the
.bss.textdata section in the output file, which apparently has the
correct attributes for a .bss section).
Fixed by adding explicit flags and type to the stack section
declaration.
[x86_64] Add support for compilation as an x86_64 binary
Currently the only supported platform for x86_64 is EFI.
Building an EFI64 gPXE requires a version of gcc that supports
__attribute__((ms_abi)). This currently means a development build of
gcc; the feature should be present when gcc 4.4 is released.
In the meantime; you can grab a suitable gcc tree from
git://git.etherboot.org/scm/people/mcb30/gcc/.git
[i386] Change [u]int32_t to [unsigned] int, rather than [unsigned] long
This brings us in to line with Linux definitions, and also simplifies
adding x86_64 support since both platforms have 2-byte shorts, 4-byte
ints and 8-byte long longs.
The userptr_t is now the fundamental type that gets used for conversions.
For example, virt_to_phys() is implemented in terms of virt_to_user() and
user_to_phys().
[i386] Simplify linker script and standardise linker-defined symbol names
Reduce the number of sections within the linker script to match the
number of practical sections within the output file.
Define _section, _msection, _esection, _section_filesz, _section_memsz,
and _section_lma for each section, replacing the mixture of symbols that
previously existed.
In particular, replace _text and _end with _textdata and _etextdata, to
make it explicit within code that uses these symbols that the .text and
.data sections are always treated as a single contiguous block.
[relocate] Guard against systems that report empty memory regions
If the INT 15,e820 memory map reports a region [0,0), this confuses
the "truncate to even megabytes" logic, which ends up rounding the
region 'down' to [0,fff00000).
Fix by ensuring that the region's end address is at least 1, before we
subtract 1 to obtain the "last byte in region" address.
[pcbios] Support arbitrary splits of the e820 memory map
Allow for an arbitrary number of splits of the system memory map via
INT 15,e820.
Features of the new map-mangling algorithm include:
Supports random access to e820 map entries.
Requires only sequential access support from the underlying e820
map, even if our caller uses random access.
Empty regions will always be stripped.
Always terminates with %ebx=0, even if the underlying map terminates
with CF=1.
Allows for an arbitrary number of hidden regions, with underlying
regions split into as many subregions as necessary.
Total size increase to achieve this is 193 bytes.
When the 16-bit segment registers are accessed using 32-bit instructions
the high order bytes are undefined on older CPUs. We now explicitly
zero the high order bytes when snapshotting the CPU state. This ensures
that the GDB stub reports consistent values for the segment registers.
The GDBSYM config.h option was an attempt at QEMU GDB debugging. I have
removed the code since it is unused and may confuse people wanting to
use the GDB stub.
Timer subsystem initialization code in core/timer.c
Split the BIOS and RTDSC timer drivers from i386_timer.c
Split arch/i386/firmware/pcbios/bios.c into the RTSDC
timer driver and arch/i386/core/nap.c
Split the headers properly:
include/unistd.h - delay functions to be used by the
gPXE core and drivers.
include/gpxe/timer.h - the fimer subsystem interface
to be used by the timer drivers
and currticks() to be used by
the code gPXE subsystems.
include/latch.h - removed
include/timer.h - scheduled for removal. Some driver
are using currticks, which is
only for core subsystems.
Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Experimentation reveals that gcc ignores -mrtd for the implicit
arithmetic functions (e.g. __udivdi3), but not for the implicit
memcpy() and memset() functions. Mark the implicit arithmetic
functions with __attribute__((cdecl)) to compensate for this.
(Note: we cannot mark with with __cdecl, because we define __cdecl to
incorporate regparm(0) as well.)
Michael Brown