From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH 0/2] ARM SMMU fixes Date: Tue, 15 Apr 2014 17:55:07 +0200 Message-ID: <15544035.e9eK8n7TO4@avalon> References: <1393601830-4677-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> <53440057.6020703@arm.com> <20140414165858.GI12916@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140414165858.GI12916-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Will Deacon Cc: Marc Zyngier , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: iommu@lists.linux-foundation.org Hi Will, On Monday 14 April 2014 17:58:58 Will Deacon wrote: > On Tue, Apr 08, 2014 at 02:57:43PM +0100, Marc Zyngier wrote: > > On 08/04/14 14:41, Laurent Pinchart wrote: > > > I've obviously forgotten that Will was away for a month. CC'ing Marc > > > Zyngier. > > > > > > On Thursday 03 April 2014 01:52:55 Laurent Pinchart wrote: > > >> On Friday 28 February 2014 16:37:08 Laurent Pinchart wrote: > > >>> Hello Will, > > >>> > > >>> I've studied your arm-smmu driver as a base to write a Renesas IOMMU > > >>> driver and found two small issues. Here are patches to fix them. > > >>> Please bear with me if my understanding was incorrect and the patches > > >>> wrong :-) > > >>> > > >>> Laurent Pinchart (2): > > >>> iommu/arm-smmu: Replace list walk with platform driver data > > >>> iommu/arm-smmu: Return 0 on unmap failure > > >>> > > >>> drivers/iommu/arm-smmu.c | 17 +++++------------ > > >>> 1 file changed, 5 insertions(+), 12 deletions(-) > > >> > > >> Do you plan to take these patches (or at least patch 2/2) in your tree > > >> ? I can send a pull request to Joerg if you give me your acked-by. > > > > > > Marc, would you like to handle this, or would you prefer to wait until > > > Will comes back ? > > > > Hi Laurent, > > > > Yup, I'll have a look and stash them in a temp tree. Given that Will > > will be back in about a week, he will have the final say. > > I've already got the fix queued ("Return 0 on unmap failure") and plan to > send it to Joerg this week. Thank you. > I think the other patch doesn't really add anything to the driver :) Fair enough, it's your driver, so the decision is yours :-) On a different but related topic, I've written an ipmmu-vmsa.c driver for a Renesas IOMMU. The IP core has custom registers but uses VMSA-compatible page tables. What would you think about sharing the page table management code between the two drivers ? The biggest difference between the two implementations is that I've hardcoded the long descriptor format, while you have reused more system MMU macros that make the arm-smmu driver use 2 or 3 levels of page tables depending on whether LPAE is disabled or enabled. -- Regards, Laurent Pinchart