coreboot/payloads/libpayload
Aaron Durbin 3c9d03d22d libpayload: usb mass storage detect empty media
There is currently a hard-coded 30 sec delay in the mass storage
driver while waiting for each device to become ready. However, mass
storage card readers that are empty return an error code on the
TEST UNIT READY command. A REQUEST SENSE command then needs to be
issued and interrogate the data to determine if no media is present.
If no media determination is found to be true the USB device is no
longer considered a candidate to be a disk.

This code does lead to the fact that the media card reader needs to be
populated at enumeration time. I suspect this is not an issue as it
appears the storage stack in libpayload can't handle removable media
coming online later.

BUG=chrome-os-partner:19596
BRANCH=None
TEST=Booted recovery and dev modes. Noted that removable mass storage
     devices with no media were ignored without any boot delay.

Change-Id: Ida7a45614d97c6e6fbfc9bb099765aad4df550fd
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/57828
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
2013-06-06 16:19:39 -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 detect empty media 2013-06-06 16:19:39 -07:00
include libpayload: expose cbfs ram functions 2013-05-24 16:27:51 -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.