790b5cf442
This patch introduces a new coreboot table entry named "has_external_display" to understand if external display is attached. This information is useful to prevent graceful shutdown by payload when the LID is closed but an external display is present. This piece of the information will be gathered by coreboot and passed into the payload using this new entry aka external_display because payload (i.e., deptcharge) doesn't have any other way to determine if external display is available. BUG=b:299137940 TEST=Able to build and boot google/rex. w/o this patch: LID closed and external display attached (HDMI) in developer mode (GBB 0x39): > System is powered off by depthcharge w/ this patch: LID closed and external display attached (HDMI) in developer mode (GBB 0x39): > Booted to OS and device is alive/usable Change-Id: I0fa7eee4c5a50371a7a66c6ca1ac2c7d046d010b Signed-off-by: Subrata Banik <subratabanik@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/77796 Reviewed-by: Eric Lai <ericllai@google.com> Reviewed-by: Nick Vaccaro <nvaccaro@google.com> Reviewed-by: Julius Werner <jwerner@chromium.org> Tested-by: build bot (Jenkins) <no-reply@coreboot.org> |
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.. | ||
arch | ||
bin | ||
configs | ||
crypto | ||
curses | ||
drivers | ||
gdb | ||
include | ||
libc | ||
libcbfs | ||
liblz4 | ||
liblzma | ||
libpci | ||
sample | ||
tests | ||
vboot | ||
.gitignore | ||
Doxyfile | ||
Kconfig | ||
LICENSE_GPL | ||
LICENSES | ||
Makefile | ||
Makefile.inc | ||
Makefile.payload | ||
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 $ make install (optional, will install into ./install per default) On x86 systems, libpayload will always be 32-bit even if your host OS runs in 64-bit, so you might have to install the 32-bit libgcc version. On Debian systems you'd do 'apt-get install gcc-multilib' for example. Run 'make distclean' before switching boards. This command will remove your current .config file, so you need 'make menuconfig' again or 'make defconfig' in order to set up configuration. Default configuration is based on 'configs/defconfig'. See the configs/ directory for examples of configuration. 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.