69eea7c01a
EHCI controllers see transfers as a queue of transfer descriptors (qTDs), each of which can represent an aligned area of up to 20KB. Each qTD is processed separately, which means that a single USB packet cannot span multiple qTDs. While this should not be a problem according to the specification, some USB storage devices seem to get confused when a packet in the middle of a transfer is smaller than the maximum packet size (512 bytes) due to falling on a qTD boundary. This patch aligns the total transfer length per qTD to 512 bytes to avoid that problem (any excess bytes will simply roll over to the next qTD). Change-Id: I0b5db07507699a3861b30c1a5ee774c45dda7fdd Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/2651 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <patrick@georgi-clan.de> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com> |
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.. | ||
arch | ||
bin | ||
configs | ||
crypto | ||
curses | ||
drivers | ||
include | ||
libc | ||
libcbfs | ||
liblzma | ||
libpci | ||
sample | ||
util | ||
Config.in | ||
Doxyfile | ||
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 http://coreboot.org for details on coreboot. Installation ------------ $ git clone http://review.coreboot.org/p/coreboot.git $ cd 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.