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Julius Werner ba11d6fec1 armv7: Change all memory domains to Client so XN bits work
Remember the XN bit? The one we had so much fun with on Nyan (LPAE)
because not setting it allows random instruction prefetches to device
memory that hang the system every few thousand boots? Thankfully, we had
always been setting it in the non-LPAE MMU code already...

"When the XN bit is 1, a Permission fault is generated if the processor
attempts to execute an instruction fetched from the corresponding memory
region. However, when using the Short-descriptor translation table
format, the fault is generated only if the access is to memory in the
Client domain, see Domains[...]" - ARM A.R.M. section B3.7.2

Oops. This patch changes our Domain Access Control Register (DACR) to
set domain 0 (the only one we are using) to Client. This means that
access permissions (AP[2:0] bits) become enforced, but they are already
set to full access (0b011). It also means that non-LPAE systems will not
be allowed to execute from DCACHE_OFF memory with enabled MMU anymore.
As far as I can see, Veyron_Pinky has been the only board that does
that.

BUG=chrome-os-partner:32118
TEST=Booted Veyron_Pinky with MMU in the bootblock, saw hangs that look
like spurious prefetches and confirmed that this patch fixes them.

Change-Id: I81c00743f938924a5dc8825389fe512a069b77db
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: cbc96db296a41ae700371a8515a1179c142f58e7
Original-Change-Id: I30676a5bfe12d516e5f910f51ee6854f6e5be557
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/223783
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/9343
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-04-08 09:27:36 +02:00
3rdparty@2bc495fd31 3rdparty: Update submodule to get Tegra 132 binaries 2015-03-07 17:50:58 +01:00
documentation documentation: define downstream data consumption rules 2015-04-07 00:20:13 +02:00
payloads libpayload: usb: xhci: set ENT flag in last Normal TRB 2015-03-23 18:41:18 +01:00
src armv7: Change all memory domains to Client so XN bits work 2015-04-08 09:27:36 +02:00
util timestamp: Add bootblock start and end to timestamp constants 2015-04-08 08:48:04 +02:00
.gitignore .gitignore: add the doxygen directory. 2014-12-14 23:30:45 +01:00
.gitmodules nvidia/cbootimage: avoid upstream's build system 2014-10-02 10:26:58 +02:00
.gitreview add .gitreview 2012-11-01 23:13:39 +01:00
COPYING
Makefile build system: run linker scripts through the preprocessor 2015-04-06 19:14:00 +02:00
Makefile.inc build system: also use ramstage CPPFLAGS for ACPI 2015-04-07 18:23:05 +02:00
README Update README with newer version of the text from the web page 2011-06-15 10:16:33 +02:00
toolchain.inc mips: mips, not mipsel 2015-03-29 22:38:57 +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.