coreboot/payloads/libpayload
Aaron Durbin 3899ec4ede libpayload: usb mass storage card hot plug
Mass storage devices such as card readers show up as
as USB devices. However the media not be inserted. In those
situations the previous code would just fake a disk and
call usbcreate_disk. This is inappropriate because it forms
a 1:1 mapping of USB device to disk leading to the inability
to remove the disk and/or handle "hot plug" card insertion
and removals.

To alleviate this issue introduce the notion of ready to the
usbmsc structure. It tracks detached, not ready, and ready
states. The polling routine is then used to track not ready
to ready transitions thereby creating and removing disks
appropriately. This handles the case of inserting and removing
a card that shows up as a new disk.

BUG=chrome-os-partner:19596
BUG=chrome-os-parnter:20014
BRANCH=None
TEST=Booted recovery mode. Able to observe inerstion and removal
     of sdcard. Also able to insert valid USB flash drive to boot
     as well.

Change-Id: I3eefbe537ec1b9c975744b8984b06c17ae236f40
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/57948
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
2013-06-09 15:03:16 -07:00
..
arch libpayload: place dummy_media.c in correct object list 2013-06-03 14:33:01 -07:00
bin libpayload: fix compiler flags 2013-02-15 06:51:52 +01:00
configs peppy: Initial mainboard commit 2013-05-28 12:53:54 -07:00
crypto Change TARGET_I386 to ARCH_X86 2012-11-30 23:20:54 +01:00
curses PDCurses: pdcscrn.c: Use #ifdef instead of #if CONFIG_SPEAKER 2013-04-01 23:24:38 +02:00
drivers libpayload: usb mass storage card hot plug 2013-06-09 15:03:16 -07:00
include libpayload: usb mass storage card hot plug 2013-06-09 15:03:16 -07:00
libc libpayload: fix size_t handling 2013-03-26 19:35:28 +01:00
libcbfs libpayload: expose cbfs ram functions 2013-05-24 16:27:51 -07:00
liblzma libpayload: Don't do unaligned accesses during LZMA decompression 2013-03-13 23:42:09 +01:00
libpci libpayload: minor cleanups 2012-04-04 00:40:31 +02:00
sample fix compilation of hello.elf example payload. 2010-08-28 23:23:47 +00:00
tests libpayload: initial test case + tiny "framework" 2013-03-22 00:35:32 +01:00
util libpayload: Fix xcompile 2013-05-21 20:14:26 -07:00
Config.in libpayload: Add USB support for non-PCI controllers 2013-05-20 17:01:26 -07:00
Doxyfile Run doxygen -u on doxygen configuration files 2010-06-28 10:40:38 +00:00
LICENSES Since some people disapprove of white space cleanups mixed in regular commits 2010-04-27 06:56:47 +00:00
Makefile libpayload: Fix the config file dependency in the Makefile template 2013-03-18 20:46:09 +01:00
Makefile.inc libpayload: Don't sneak in compiler includes 2013-04-09 13:45:42 -07:00
README libpayload, superiotool: README: Prepend coreboot/ to path of change directory line 2013-04-04 17:22:15 +02:00

-------------------------------------------------------------------------------
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 http://coreboot.org for details on coreboot.


Installation
------------

 $ git clone http://review.coreboot.org/p/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 http://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at http://coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.