From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755992Ab2DXI2s (ORCPT ); Tue, 24 Apr 2012 04:28:48 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:56214 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753831Ab2DXI2p (ORCPT ); Tue, 24 Apr 2012 04:28:45 -0400 Date: Tue, 24 Apr 2012 09:28:10 +0100 From: Catalin Marinas To: Yilu Mao Cc: "linux-kernel@vger.kernel.org" , "linux@arm.linux.org.uk" , "Baohua.Song@csr.com" , "santosh.shilimkar@ti.com" , "robherring2@gmail.com" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] ARM: cache-l2x0.c: save aux ctrl for resume in case that l2x0 is enabled before init Message-ID: <20120424082810.GA9367@arm.com> References: <1335235280-25148-1-git-send-email-ylmao@marvell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1335235280-25148-1-git-send-email-ylmao@marvell.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 24, 2012 at 03:41:20AM +0100, Yilu Mao wrote: > If l2x0 controller has been enabled when calling l2x0_init, the aux ctrl > register will not be saved in l2x0_saved_regs. Therefore we can not use > l2x0_saved_regs.aux_ctrl for resume later. This patch fixed the problem > by saving aux ctrl in l2x0_saved_regs just after it's being read from > the register. > > Signed-off-by: Yilu Mao > --- > arch/arm/mm/cache-l2x0.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c > index a53fd2a..3034b06 100644 > --- a/arch/arm/mm/cache-l2x0.c > +++ b/arch/arm/mm/cache-l2x0.c > @@ -320,6 +320,12 @@ void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask) > cache_id = readl_relaxed(l2x0_base + L2X0_CACHE_ID); > aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL); > > + /* In case l2x controller is enabled, the aux ctrl register > + * can't be set. So the original value should be stored in > + * the l2x0_saved_regs for restoring when resume. > + */ Even better like this ;) + /* + * In case l2x controller is enabled, the aux ctrl register + * can't be set. So the original value should be stored in + * the l2x0_saved_regs for restoring when resume. + */ > + l2x0_saved_regs.aux_ctrl = aux; > + > aux &= aux_mask; > aux |= aux_val; I think that's the wrong place to save it, it should be after the masking was done. Anyway, if we cannot write this register in l2x0_init() because the L2 was enabled, do we expect the L2 to be disabled during resume? -- Catalin From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Tue, 24 Apr 2012 09:28:10 +0100 Subject: [PATCH] ARM: cache-l2x0.c: save aux ctrl for resume in case that l2x0 is enabled before init In-Reply-To: <1335235280-25148-1-git-send-email-ylmao@marvell.com> References: <1335235280-25148-1-git-send-email-ylmao@marvell.com> Message-ID: <20120424082810.GA9367@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Apr 24, 2012 at 03:41:20AM +0100, Yilu Mao wrote: > If l2x0 controller has been enabled when calling l2x0_init, the aux ctrl > register will not be saved in l2x0_saved_regs. Therefore we can not use > l2x0_saved_regs.aux_ctrl for resume later. This patch fixed the problem > by saving aux ctrl in l2x0_saved_regs just after it's being read from > the register. > > Signed-off-by: Yilu Mao > --- > arch/arm/mm/cache-l2x0.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c > index a53fd2a..3034b06 100644 > --- a/arch/arm/mm/cache-l2x0.c > +++ b/arch/arm/mm/cache-l2x0.c > @@ -320,6 +320,12 @@ void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask) > cache_id = readl_relaxed(l2x0_base + L2X0_CACHE_ID); > aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL); > > + /* In case l2x controller is enabled, the aux ctrl register > + * can't be set. So the original value should be stored in > + * the l2x0_saved_regs for restoring when resume. > + */ Even better like this ;) + /* + * In case l2x controller is enabled, the aux ctrl register + * can't be set. So the original value should be stored in + * the l2x0_saved_regs for restoring when resume. + */ > + l2x0_saved_regs.aux_ctrl = aux; > + > aux &= aux_mask; > aux |= aux_val; I think that's the wrong place to save it, it should be after the masking was done. Anyway, if we cannot write this register in l2x0_init() because the L2 was enabled, do we expect the L2 to be disabled during resume? -- Catalin