Rockbox
5aa19f3eeb
CPU frequency scaling is basically useless without scaling the memory frequency. On the i.MX233, the EMI (external memory interface) and DRAM blocks are responsable for the DDR settings. This commits implements emi frequency scaling. Only some settings are implemented and the timings values only apply to mDDR (extracted from Sigmatel linux port) and have been checked to work on the Fuze+ and Zen X-Fi2/3. This feature is still disabled by default but I expected some battery life savings by boosting higher to 454MHz and unboosting lower to 64MHz. Note that changing the emi frequency is particularly tricky and to avoid writing it entirely in assembly we rely on the compiler to not use the stack except in the prolog and epilog (because it's in dram which is disabled when doing the change) and to put constant pools in iram which should always be true if the compiler isn't completely dumb and since the code itself is put in iram. If this proves to be insufficient, one can always switch the stack to the irq stack since interrupts are disabled during the change. Change-Id: If6ef5357f7ff091130ca1063e48536c6028f23ba |
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| android | ||
| apps | ||
| backdrops | ||
| bootloader | ||
| debian | ||
| docs | ||
| firmware | ||
| flash | ||
| fonts | ||
| gdb | ||
| icons | ||
| lib | ||
| manual | ||
| packaging | ||
| rbutil | ||
| tools | ||
| uisimulator | ||
| utils | ||
| wps | ||
| .gitattributes | ||
| .gitignore | ||
__________ __ ___.
Open \______ \ ____ ____ | | _\_ |__ _______ ___
Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
\/ \/ \/ \/ \/
Build Your Own Rockbox
1. Check out 'rockbox' from SVN (or extract a downloaded archive).
$ svn co svn://svn.rockbox.org/rockbox/trunk rockbox
or
$ tar xjf rockbox.tar.bz2
2. Create a build directory, preferably in the same directory as the firmware/
and apps/ directories. This is where all generated files will be written.
$ cd rockbox
$ mkdir build
$ cd build
3. Make sure you have sh/arm/m68k-elf-gcc and siblings in the PATH. Make sure
that you have 'perl' in your PATH too. Your gcc cross compiler needs to be
a particular version depending on what player you are compiling for. These
can be acquired with the rockboxdev.sh script in the /tools/ folder of the
source, or will have been included if you've installed one of the
toolchains or development environments provided at http://www.rockbox.org/
$ which sh-elf-gcc
$ which perl
4. In your build directory, run the 'tools/configure' script and enter what
target you want to build for and if you want a debug version or not (and a
few more questions). It'll prompt you. The debug version is for making a
gdb version out of it. It is only useful if you run gdb towards your target
Archos.
$ ../tools/configure
5. *ploink*. Now you have got a Makefile generated for you.
6. Run 'make' and soon the necessary pieces from the firmware and the apps
directories have been compiled, linked and scrambled for you.
$ make
$ make zip
7. unzip the rockbox.zip on your music player, reboot it and
*smile*.
If you want to build for more than one target, just create several build
directories and create a setup for each target:
$ mkdir build-fmrecorder
$ cd build-fmrecorder
$ ../tools/configure
$ mkdir build-player
$ cd build-player
$ ../tools/configure
Questions anyone? Ask on the mailing list. We'll be happy to help you!