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Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (257 commits) [ARM] Update mach-types ARM: 5636/1: Move vendor enum to AMBA include ARM: Fix pfn_valid() for sparse memory [ARM] orion5x: Add LaCie NAS 2Big Network support [ARM] pxa/sharpsl_pm: zaurus c3000 aka spitz: fix resume ARM: 5686/1: at91: Correct AC97 reset line in at91sam9263ek board ARM: 5640/1: This patch modifies the support of AC97 on the at91sam9263 ek board ARM: 5689/1: Update default config of HP Jornada 700-series machines ARM: 5691/1: fix cache aliasing issues between kmap() and kmap_atomic() with highmem ARM: 5688/1: ks8695_serial: disable_irq() lockup ARM: 5687/1: fix an oops with highmem ARM: 5684/1: Add nuc960 platform to w90x900 ARM: 5683/1: Add nuc950 platform to w90x900 ARM: 5682/1: Add cpu.c and dev.c and modify some files of w90p910 platform ARM: 5626/1: add suspend/resume functions to amba-pl011 serial driver ARM: 5625/1: fix hard coded 4K resource size in amba bus detection MMC: MMCI: convert realview MMC to use gpiolib ARM: 5685/1: Make MMCI driver compile without gpiolib ARM: implement highpte ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ ... Fix up trivial conflict in arch/arm/kernel/signal.c. It was due to the TIF_NOTIFY_RESUME addition in commit d0420c8 ("KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures") and follow-ups.
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S3C24XX CPUfreq support | ||
======================= | ||
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Introduction | ||
------------ | ||
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The S3C24XX series support a number of power saving systems, such as | ||
the ability to change the core, memory and peripheral operating | ||
frequencies. The core control is exported via the CPUFreq driver | ||
which has a number of different manual or automatic controls over the | ||
rate the core is running at. | ||
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There are two forms of the driver depending on the specific CPU and | ||
how the clocks are arranged. The first implementation used as single | ||
PLL to feed the ARM, memory and peripherals via a series of dividers | ||
and muxes and this is the implementation that is documented here. A | ||
newer version where there is a seperate PLL and clock divider for the | ||
ARM core is available as a seperate driver. | ||
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Layout | ||
------ | ||
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The code core manages the CPU specific drivers, any data that they | ||
need to register and the interface to the generic drivers/cpufreq | ||
system. Each CPU registers a driver to control the PLL, clock dividers | ||
and anything else associated with it. Any board that wants to use this | ||
framework needs to supply at least basic details of what is required. | ||
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The core registers with drivers/cpufreq at init time if all the data | ||
necessary has been supplied. | ||
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CPU support | ||
----------- | ||
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The support for each CPU depends on the facilities provided by the | ||
SoC and the driver as each device has different PLL and clock chains | ||
associated with it. | ||
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Slow Mode | ||
--------- | ||
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The SLOW mode where the PLL is turned off altogether and the | ||
system is fed by the external crystal input is currently not | ||
supported. | ||
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sysfs | ||
----- | ||
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The core code exports extra information via sysfs in the directory | ||
devices/system/cpu/cpu0/arch-freq. | ||
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Board Support | ||
------------- | ||
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Each board that wants to use the cpufreq code must register some basic | ||
information with the core driver to provide information about what the | ||
board requires and any restrictions being placed on it. | ||
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The board needs to supply information about whether it needs the IO bank | ||
timings changing, any maximum frequency limits and information about the | ||
SDRAM refresh rate. | ||
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Document Author | ||
--------------- | ||
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Ben Dooks, Copyright 2009 Simtec Electronics | ||
Licensed under GPLv2 |
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