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Aaron Durbin 3d0071bde3 haswell: adjust CAR usage
It was found that the Haswell reference code was smashing through the
stack into the reference code's heap implementation. The reason for this
is because our current CAR allocation is too small. Moreover there are
quite a few things to coordinate between 2 code bases to get correct.
This commit separates the CAR into 2 parts:
  1. MRC CAR usage.
  2. Coreboot CAR usage.
Pointers from one region can be passed between the 2 modules, but one
should not be able to affect the others as checking has been put into
place in both modules.

The CAR size has effectively been doubled from 0x20000 (128 KiB) to
0x40000 (256KiB). Not all of that increase was needed, but enforcing
a power of 2 size only utilizes 1 MTRR.

Old CAR layout with a single contiguous stack with the region starting
at CONFIG_DCACHE_RAM_BASE:

+---------------------------------------+ Offset CONFIG_DCACHE_RAM_SIZE
|  MRC global variables                 |
|  CONFIG_DCACHE_RAM_MRC_VAR_SIZE bytes |
+---------------------------------------+
|  ROM stage stack                      |
|                                       |
|                                       |
+---------------------------------------+
|  MRC Heap 30000 bytes                 |
+---------------------------------------+
|  ROM stage console                    |
|  CONFIG_CONSOLE_CAR_BUFFER_SIZE bytes |
+---------------------------------------+
|  ROM stage CAR_GLOBAL variables       |
+---------------------------------------+ Offset 0

There was some hard coded offsets in the reference code wrapper to start
the heap past the console buffer. Even with this commit the console
can smash into the following region depending on what size
CONFIG_CONSOLE_CAR_BUFFER_SIZE is.

As noted above This change splits the CAR region into 2 parts starting
at CONFIG_DCACHE_RAM_BASE:

+---------------------------------------+
|  MRC Region                           |
|  CONFIG_DCACHE_RAM_MRC_VAR_SIZE bytes |
+---------------------------------------+ Offset CONFIG_DCACHE_RAM_SIZE
|  ROM stage stack                      |
|                                       |
|                                       |
+---------------------------------------+
|  ROM stage console                    |
|  CONFIG_CONSOLE_CAR_BUFFER_SIZE bytes |
+---------------------------------------+
|  ROM stage CAR_GLOBAL variables       |
+---------------------------------------+ Offset 0

Another variable was add, CONFIG_DCACHE_RAM_ROMSTAGE_STACK_SIZE,
which represents the expected stack usage for the romstage. A marker
is checked at the base of the stack to determine if either the stack
was smashed or the console encroached on the stack.

Change-Id: Id76f2fe4a5cf1c776c8f0019f406593f68e443a7
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2752
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2013-03-18 20:47:50 +01:00
3rdparty@ba8caa30bd Update 3rdparty mark to latest repository 2013-03-15 19:09:08 +01:00
documentation sconfig: rename lapic_cluster -> cpu_cluster 2013-02-14 07:07:20 +01:00
payloads libpayload: Fix the config file dependency in the Makefile template 2013-03-18 20:46:09 +01:00
src haswell: adjust CAR usage 2013-03-18 20:47:50 +01:00
util superiotool: Add support for the IT8728F Super I/O 2013-03-17 23:20:38 +01:00
.gitignore add a few entries to .gitignore 2013-01-10 22:51:20 +01:00
.gitmodules gitmodules: Ignore 3rdparty in "diff family" 2013-03-16 04:07:14 +01:00
.gitreview add .gitreview 2012-11-01 23:13:39 +01:00
COPYING
Makefile build system: Retire REQUIRES_BLOB 2013-02-19 11:00:41 +01:00
Makefile.inc rmodule: add rmodules class and new type 2013-03-18 20:46:40 +01:00
README Update README with newer version of the text from the web page 2011-06-15 10:16:33 +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
------------------

 * gcc / g++
 * make

Optional:

 * doxygen (for generating/viewing documentation)
 * iasl (for targets with ACPI support)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig')
 * 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.