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Furquan Shaikh c2973d196d spi: Get rid of SPI_ATOMIC_SEQUENCING
SPI_ATOMIC_SEQUENCING was added to accomodate spi flash controllers with
the ability to perform tx and rx of flash command and response at the
same time. Instead of introducing this notion at SPI flash driver layer,
clean up the interface to SPI used by flash.

Flash uses a command-response kind of communication. Thus, even though
SPI is duplex, flash command needs to be sent out on SPI bus and then
flash response should be received on the bus. Some specialized x86
flash controllers are capable of handling command and response in a
single transaction.

In order to support all the varied cases:
1. Add spi_xfer_vector that takes as input a vector of SPI operations
and calls back into SPI controller driver to process these operations.
2. In order to accomodate flash command-response model, use two vectors
while calling into spi_xfer_vector -- one with dout set to
non-NULL(command) and other with din set to non-NULL(response).
3. For specialized SPI flash controllers combine two successive vectors
if the transactions look like a command-response pair.
4. Provide helper functions for common cases like supporting only 2
vectors at a time, supporting n vectors at a time, default vector
operation to cycle through all SPI op vectors one by one.

BUG=chrome-os-partner:59832
BRANCH=None
TEST=Compiles successfully

Change-Id: I4c9e78c585ad95c40c0d5af078ff8251da286236
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/17681
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-12-23 04:54:55 +01:00
3rdparty 3rdparty/libgfxinit: Update to latest master 2016-12-15 23:47:53 +01:00
Documentation Documentation: Add Kconfig document 2016-11-13 21:41:44 +01:00
configs configs: Add some sample default configuration files 2016-12-09 00:34:50 +01:00
payloads libpayload: Get current tick from high register in generic timer 2016-12-21 20:26:39 +01:00
src spi: Get rid of SPI_ATOMIC_SEQUENCING 2016-12-23 04:54:55 +01:00
util util/romcc: Don't read 'member' if it might be NULL 2016-12-16 18:45:56 +01:00
.checkpatch.conf Update .checkpatch.conf 2016-09-02 18:22:04 +02:00
.clang-format
.gitignore .gitignore: Do not track `intelmetool` binary 2016-11-29 17:29:52 +01:00
.gitmodules Set up 3rdparty/libgfxinit 2016-10-29 01:35:03 +02:00
.gitreview add .gitreview 2012-11-01 23:13:39 +01:00
COPYING
MAINTAINERS MAINTAINERS: Add lowrisc files to RISC-V 2016-11-12 19:30:26 +01:00
Makefile Makefile: Allow inclusion of source files from 3rdparty/ 2016-10-29 01:34:06 +02:00
Makefile.inc Makefile.inc: Update what-jenkins-does target 2016-12-12 17:45:41 +01:00
README Remove extra newlines from the end of all coreboot files. 2016-07-31 18:19:33 +02:00
gnat.adc gnat.adc: Do not generate assertion code for Refined_Post 2016-10-29 01:33:31 +02:00
toolchain.inc Add minimal GNAT run time system (RTS) 2016-09-19 11:14:49 +02:00

README

-------------------------------------------------------------------------------
coreboot README
-------------------------------------------------------------------------------

coreboot is a Free Software project aimed at replacing the proprietary BIOS
(firmware) found in most computers.  coreboot performs a little bit of
hardware initialization and then executes additional boot logic, called a
payload.

With the separation of hardware initialization and later boot logic,
coreboot can scale from specialized applications that run directly
firmware, run operating systems in flash, load custom
bootloaders, or implement firmware standards, like PC BIOS services or
UEFI. This allows for systems to only include the features necessary
in the target application, reducing the amount of code and flash space
required.

coreboot was formerly known as LinuxBIOS.


Payloads
--------

After the basic initialization of the hardware has been performed, any
desired "payload" can be started by coreboot.

See http://www.coreboot.org/Payloads for a list of supported payloads.


Supported Hardware
------------------

coreboot supports a wide range of chipsets, devices, and mainboards.

For details please consult:

 * http://www.coreboot.org/Supported_Motherboards
 * http://www.coreboot.org/Supported_Chipsets_and_Devices


Build Requirements
------------------

 * make
 * gcc / g++
   Because Linux distribution compilers tend to use lots of patches. coreboot
   does lots of "unusual" things in its build system, some of which break due
   to those patches, sometimes by gcc aborting, sometimes - and that's worse -
   by generating broken object code.
   Two options: use our toolchain (eg. make crosstools-i386) or enable the
   ANY_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this
   case).
 * iasl (for targets with ACPI support)

Optional:

 * doxygen (for generating/viewing documentation)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig' and 'make nconfig')
 * flex and bison (for regenerating parsers)


Building coreboot
-----------------

Please consult http://www.coreboot.org/Build_HOWTO for details.


Testing coreboot Without Modifying Your Hardware
------------------------------------------------

If you want to test coreboot without any risks before you really decide
to use it on your hardware, you can use the QEMU system emulator to run
coreboot virtually in QEMU.

Please see http://www.coreboot.org/QEMU for details.


Website and Mailing List
------------------------

Further details on the project, a FAQ, many HOWTOs, news, development
guidelines and more can be found on the coreboot website:

  http://www.coreboot.org

You can contact us directly on the coreboot mailing list:

  http://www.coreboot.org/Mailinglist


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

The copyright on coreboot is owned by quite a large number of individual
developers and companies. Please check the individual source files for details.

coreboot is licensed under the terms of the GNU General Public License (GPL).
Some files are licensed under the "GPL (version 2, or any later version)",
and some files are licensed under the "GPL, version 2". For some parts, which
were derived from other projects, other (GPL-compatible) licenses may apply.
Please check the individual source files for details.

This makes the resulting coreboot images licensed under the GPL, version 2.