Difference between revisions of "Libpayload"

Revision as of 19:38, 7 March 2008

libpayload is a small BSD-licensed "library" (a lightweight implementation of common and useful functions) intended to be used as a basis for coreboot payloads.

Overview

The benefits of linking a coreboot payload against libpayload are:

• Payloads do not have to implement and maintain low-level code for I/O, common functions, etc.
• Payloads can be recompiled and deployed for CPU architectures supported by coreboot in the future.
• The libpayload functions can be tested and scrutinized outside payload development.
• Payloads themselves may be partly host-tested, e.g. against an emulation libpayload.
• Leads to the possibility of payloads using dynamic linking, reducing total payload footprint.

Just give us a main() and a pocket full of dreams and we'll do the rest.

Feature Wish List

• Basics
  • coreboot services and structures (e.g. read CMOS, device tree)
  • subset of C-library functions (e.g. printf, puts, getch)
  • light ncurses from the Google Summer Of Code project
• Fancies
  • directFB
  • TWIN

Libc Coverage

Usage Example

hello_payload.c:

#include <libpayload.h>

int main(void)
{
    printf("Hello, world!\n");
    halt();
    return 0;
}

Build example (basic idea):

gcc -o hello_payload hello_payload.c

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