From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH v2 08/11] of: Increase MAX_PHANDLE_ARGS Date: Wed, 29 Jan 2014 18:03:50 +0000 Message-ID: <20140129180350.GS26622@mudshark.cambridge.arm.com> References: <1389876263-25759-1-git-send-email-andreas.herrmann@calxeda.com> <1389876263-25759-9-git-send-email-andreas.herrmann@calxeda.com> <20140117110830.GW3471@alberich> <52E92842.3000001@amd.com> <52E93360.1000904@amd.com> <20140129171611.GB13543@alberich> <52E939CB.1020705@amd.com> <20140129172932.GQ26622@mudshark.cambridge.arm.com> <52E940FC.9050602@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <52E940FC.9050602-5C7GfCeVMHo@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: Suravee Suthikulanit Cc: "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , Rob Herring , Rob Herring , Andreas Herrmann , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: devicetree@vger.kernel.org On Wed, Jan 29, 2014 at 05:57:16PM +0000, Suravee Suthikulanit wrote: > On 1/29/2014 11:29 AM, Will Deacon wrote: > > On Wed, Jan 29, 2014 at 05:26:35PM +0000, Suravee Suthikulanit wrote: > >> On 1/29/2014 11:16 AM, Andreas Herrmann wrote: > >>> On Wed, Jan 29, 2014 at 11:59:12AM -0500, Suravee Suthikulanit wrote: > >>>> Actually, we are using 32 on the AMD system. So, do you think we can set > >>>> this to 32 instead? > >>> > >>> I think that's ok. > >>> > >>> But are we really talking about number of SMRs or number of StreamIDs > >>> per master device here? Ie. are you just having 32 SMRs for an SMMU on > >>> your AMD system or do you have master devices which have 32 StreamIDs? > >>> > >>> If it's just number of SMRs we don't need to modify this macro. > >>> > >> > >> I am referring to the case where each mmu-master can have upto 32 streamID. > > > > Crikey, how many SMRs do you have? Andreas and I have been struggling to > > write a decent allocator for those, so if you have any algorithms that don't > > require a quantum computer, we'd love to hear from you :)! > > > > Will > > > > Are you talking about the __arm_smmu_alloc_bitmap()? > > Currently, we have configured the each SMMU to have 32 SMRs and using > 15-bit streamID. However, we mostly have upto 32 streamID for each > master, and most of the SMMU only have one master. So it looks like the > current logic should be ok. Interesting... how does that work for PCI? Do you force all devices behind a given RC into the same address space? Will From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Wed, 29 Jan 2014 18:03:50 +0000 Subject: [PATCH v2 08/11] of: Increase MAX_PHANDLE_ARGS In-Reply-To: <52E940FC.9050602@amd.com> References: <1389876263-25759-1-git-send-email-andreas.herrmann@calxeda.com> <1389876263-25759-9-git-send-email-andreas.herrmann@calxeda.com> <20140117110830.GW3471@alberich> <52E92842.3000001@amd.com> <52E93360.1000904@amd.com> <20140129171611.GB13543@alberich> <52E939CB.1020705@amd.com> <20140129172932.GQ26622@mudshark.cambridge.arm.com> <52E940FC.9050602@amd.com> Message-ID: <20140129180350.GS26622@mudshark.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Jan 29, 2014 at 05:57:16PM +0000, Suravee Suthikulanit wrote: > On 1/29/2014 11:29 AM, Will Deacon wrote: > > On Wed, Jan 29, 2014 at 05:26:35PM +0000, Suravee Suthikulanit wrote: > >> On 1/29/2014 11:16 AM, Andreas Herrmann wrote: > >>> On Wed, Jan 29, 2014 at 11:59:12AM -0500, Suravee Suthikulanit wrote: > >>>> Actually, we are using 32 on the AMD system. So, do you think we can set > >>>> this to 32 instead? > >>> > >>> I think that's ok. > >>> > >>> But are we really talking about number of SMRs or number of StreamIDs > >>> per master device here? Ie. are you just having 32 SMRs for an SMMU on > >>> your AMD system or do you have master devices which have 32 StreamIDs? > >>> > >>> If it's just number of SMRs we don't need to modify this macro. > >>> > >> > >> I am referring to the case where each mmu-master can have upto 32 streamID. > > > > Crikey, how many SMRs do you have? Andreas and I have been struggling to > > write a decent allocator for those, so if you have any algorithms that don't > > require a quantum computer, we'd love to hear from you :)! > > > > Will > > > > Are you talking about the __arm_smmu_alloc_bitmap()? > > Currently, we have configured the each SMMU to have 32 SMRs and using > 15-bit streamID. However, we mostly have upto 32 streamID for each > master, and most of the SMMU only have one master. So it looks like the > current logic should be ok. Interesting... how does that work for PCI? Do you force all devices behind a given RC into the same address space? Will