This commit implements GDB over UDP. Using UDP is more complex than
serial and has required some restructuring.
The GDB stub is now built using one or both of GDBSERIAL and GDBUDP
config.h options.
To enter the debugger, execute the gPXE shell command:
gdbstub <transport> [<options>...]
Where <transport> is "serial" or "udp". For "udp", the name of a
configured network device is required:
gdbstub udp net0
The GDB stub listens on UDP port 43770 by default.
Avoid calling cpu_nap() until after we have determined that there is
no input ready to read. This avoids delaying for one timer interrupt
(~50ms) in the case of
if ( iskey() )
char = getkey()
which happens to be present in monojob.c, which is where we spend most
of our time looping (e.g. during any download).
This should eliminate the irritating tendency of gPXE to lose
keypresses.
Discovered on a Dell system where the serial port seems to send in a
constant stream of 0xff characters; this wouldn't be a problem in
itself except that each one triggers the 50ms delay (as mentioned
above), which really kills performance.
Delete ELF as a generic image type. The method for invoking an
ELF-based image (as well as any tables that must be set up to allow it
to boot) will always depend on the specific architecture. core/elf.c
now only provides the elf_load() function, to avoid duplicating
functionality between ELF-based image types.
Add arch/i386/image/elfboot.c, to handle the generic case of 32-bit
x86 ELF images. We don't currently set up any multiboot tables, ELF
notes, etc. This seems to be sufficient for loading kernels generated
using both wraplinux and coreboot's mkelfImage.
Note that while Etherboot 5.4 allowed ELF images to return, we don't.
There is no callback mechanism for the loaded image to shut down gPXE,
which means that we have to shut down before invoking the image. This
means that we lose device state, protection against being trampled on,
etc. It is not safe to continue afterwards.
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.
Various specification documents disagree about the byte ordering of
UUIDs. However, SMBIOS seems to use the standard in which everything is
in network-endian order.
This doesn't affect anything sent on the wire; only what gets printed on
the screen when the "uuid" variable is displayed.
Allow for settings to be described by something other than a DHCP option
tag if desirable. Currently used only for the MAC address setting.
Separate out fake DHCP packet creation code from dhcp.c to fakedhcp.c.
Remove notion of settings from dhcppkt.c.
Rationalise dhcp.c to use settings API only for final registration of the
DHCP options, rather than using {store,fetch}_setting throughout.
Add the notion of the settings hierarchy, complete with
register/unregister routines.
Rename set->store and get->fetch to avoid naming conflicts with get/put
as used in reference counting.
Add the concept of an abstract configuration setting, comprising a (DHCP)
tag value and an associated byte sequence.
Add the concept of a settings namespace.
Add functions for extracting string, IPv4 address, and signed and
unsigned integer values from configuration settings (analogous to
dhcp_snprintf(), dhcp_ipv4_option(), etc.).
Update functions for parsing and formatting named/typed options to work
with new settings API.
Update NVO commands and config UI to use new settings API.
Timers are sometimes required before the call to initialise(), so we
cannot rely on initialise() to set up the timers before use.
Also fix a potential integer overflow issue in generic_currticks_udelay()
Add missing comments to timer code.
Lock system if no suitable timer source is found.
Fix initialisation order so that timers are initialised before code that
needs to use them.
Allow encapsulated options to be specified as e.g. "175.3". As a
side-effect, change the separator character for the type field from "." to
":"; for example, the IP address pseudo-option is now "175.3:ipv4".
Add parse and display routines for 16-bit and 32-bit integer configuration
settings.
Add parse and display routines for hex-string configuration settings.
Assume hex-string as a configuration setting type if no type is explicitly
specified.
show_setting() and related functions now return an "actual length" in the
style of snprintf(). This is to allow consumers to allocate buffers large
enough to hold the formatted setting.
Replace a printf with a DBG in timer_rtdsc.c
Replace a printf in timer.c with assert
Return proper error codes from timer drivers
Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
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.)
Stefan Hajnoczi