From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Tue, 17 Jun 2014 11:23:44 +0100 Subject: ARM diagnostic register across suspend/resume In-Reply-To: <20140617102123.GA13808@arm.com> References: <20140617083117.GD8860@dragon> <20140617095729.GF13020@arm.com> <20140617101606.GE23430@n2100.arm.linux.org.uk> <20140617102123.GA13808@arm.com> Message-ID: <20140617102344.GG23430@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Jun 17, 2014 at 11:21:23AM +0100, Will Deacon wrote: > I think that actually works ok, because writing zeroes doesn't actually > do anything as far as I understand. The problem with suspend/resume is > that the suspend/resume cycle could well clear the internal state and > writing zeroes won't re-enable the workaround bits. > > I'll double-check this with the hardware guys, since this register really > is undocumented. Are you saying that it is write one to set, and writing zero is ignored? If that's true, we should simplify the work-around code to get rid of the read-modify-write. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it.