ca52a25882
This patch adds the new, faster architectural register accessors to libpayload that were already added to coreboot in CB:27881. It also hardcodes the assumption that coreboot payloads run at EL2, which has already been hardcoded in coreboot with CB:27880 (see rationale there). This means we can drop all the read_current/write_current stuff which added a lot of unnecessary helpers to check the current exception level. This patch breaks payloads that used read_current/write_current accessors, but it seems unlikely that many payloads deal with this stuff anyway, and it should be a trivial fix (just replace them with the respective _el2 versions). Also add accessors for a couple of more registers that are required to enable debug mode while I'm here. Change-Id: Ic9dfa48411f3805747613f03611f8a134a51cc46 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/29017 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> |
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.. | ||
arch | ||
bin | ||
configs | ||
crypto | ||
curses | ||
drivers | ||
gdb | ||
include | ||
libc | ||
libcbfs | ||
liblz4 | ||
liblzma | ||
libpci | ||
sample | ||
tests | ||
Doxyfile | ||
Kconfig | ||
LICENSE_GPL | ||
LICENSES | ||
Makefile | ||
Makefile.inc | ||
README |
------------------------------------------------------------------------------- libpayload README ------------------------------------------------------------------------------- libpayload is a minimal library to support standalone payloads that can be booted with firmware like coreboot. It handles the setup code, and provides common C library symbols such as malloc() and printf(). Note: This is _not_ a standard library for use with an operating system, rather it's only useful for coreboot payload development! See https://www.coreboot.org for details on coreboot. Installation ------------ $ git clone https://review.coreboot.org/coreboot.git $ cd coreboot/payloads/libpayload $ make menuconfig $ make $ sudo make install (optional, will install into /opt per default) As libpayload is for 32bit x86 systems only, you might have to install the 32bit libgcc version, otherwise your payloads will fail to compile. On Debian systems you'd do 'apt-get install gcc-multilib' for example. Usage ----- Here's an example of a very simple payload (hello.c) and how to build it: #include <libpayload.h> int main(void) { printf("Hello, world!\n"); return 0; } Building the payload using the 'lpgcc' compiler wrapper: $ lpgcc -o hello.elf hello.c Please see the sample/ directory for details. Website and Mailing List ------------------------ The main website is https://www.coreboot.org/Libpayload. For additional information, patches, and discussions, please join the coreboot mailing list at https://www.coreboot.org/Mailinglist, where most libpayload developers are subscribed. Copyright and License --------------------- See LICENSES.