From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: Re: [HELP] Power management for embedded system Date: Thu, 24 Aug 2006 10:04:55 +0100 Message-ID: <20060824090455.GA18202@flint.arm.linux.org.uk> References: <20060824084425.83538.qmail@web25802.mail.ukl.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <20060824084425.83538.qmail@web25802.mail.ukl.yahoo.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.osdl.org Errors-To: linux-pm-bounces@lists.osdl.org To: moreau francis Cc: linux-pm@lists.osdl.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org 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