Messages in this thread | | | Date | Thu, 24 Aug 2006 10:04:55 +0100 | From | Russell King <> | Subject | Re: [HELP] Power management for embedded system |
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On Thu, Aug 24, 2006 at 08:44:25AM +0000, moreau francis wrote: > Mips one seems to be a copy and paste of arm one and both of them > have removed all APM bios stuff orginally part of i386 implementation.
The BIOS stuff makes no sense on ARM - there isn't a BIOS to do anything with.
> It doesn't seem that APM is something really stable and finished.
It's complete. It's purpose is to provide the interface to userland so that programs know about suspend/resume events, and can initiate suspends. Eg, the X server.
The power management really comes from the Linux drivers themselves, which are written to peripherals off when they're not in use. The other power saving comes from things like cpufreq - again, nothing to do with the magical "APM" or "ACPI" terms.
On embedded platforms, you shouldn't think about power management in terms of the non-embedded PM technologies.
-- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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