Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751479Ab3FQObF (ORCPT ); Mon, 17 Jun 2013 10:31:05 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:43097 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062Ab3FQObD (ORCPT ); Mon, 17 Jun 2013 10:31:03 -0400 Date: Mon, 17 Jun 2013 15:30:21 +0100 From: Russell King - ARM Linux To: Arnd Bergmann Cc: Jonas Jensen , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, ulli.kroll@googlemail.com, arm@kernel.org, Florian Fainelli , Imre Kaloz Subject: Re: [PATCH] ARM: mm: cpu_fa526_do_idle: remove WFI Message-ID: <20130617143021.GI2718@n2100.arm.linux.org.uk> References: <1371476360-8751-1-git-send-email-jonas.jensen@gmail.com> <5020304.hteFFmWh1u@wuerfel> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5020304.hteFFmWh1u@wuerfel> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1899 Lines: 44 On Mon, Jun 17, 2013 at 04:14:03PM +0200, Arnd Bergmann wrote: > On Monday 17 June 2013 15:39:20 Jonas Jensen wrote: > > As it was already suggested by Russell King and Arnd Bergmann ( https://lkml.org/lkml/2013/5/16/133 ), moxart and gemini seem to be the only platforms using CPU_FA526, and instead of pointing arm_pm_idle to an empty function from platform code, it makes sense to remove WFI code from the processor specific idle function. > > > > Note: moxart boots and prints to UART without this patch, but input is broken. > > Please make sure you have proper line wraps. Lines in checkin > comments should be no longer than 70 characters normally. > > > Signed-off-by: Jonas Jensen > > Acked-by: Arnd Bergmann > > Since this patch is independent from the actual platform support, > it should go through Russell's patch tracker at > http://www.arm.linux.org.uk/developer/patches/ Except... the patch is wrong. > > arch/arm/mm/proc-fa526.S | 4 +--- > > 1 files changed, 1 insertions(+), 3 deletions(-) > > > > diff --git a/arch/arm/mm/proc-fa526.S b/arch/arm/mm/proc-fa526.S > > index d217e97..85280b1 100644 > > --- a/arch/arm/mm/proc-fa526.S > > +++ b/arch/arm/mm/proc-fa526.S > > @@ -81,9 +81,7 @@ ENDPROC(cpu_fa526_reset) > > */ > > .align 4 > > ENTRY(cpu_fa526_do_idle) > > - mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt > > - mov pc, lr > > - > > + nop It replaces the WFI and return with a pure nop, so we will fall through to cpu_fa526_dcache_clean_area(). Do we really want to clean a random D cache entry depending on what r0 happened to hold at this point? I think not... -- 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/