From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH v5 01/14] drivers: iommu: add FWNODE_IOMMU fwnode type Date: Thu, 29 Sep 2016 22:59:40 +0200 Message-ID: <3178073.UTpgCTN6if@vostro.rjw.lan> References: <20160909142343.13314-1-lorenzo.pieralisi@arm.com> <20160909142343.13314-2-lorenzo.pieralisi@arm.com> <20160929141520.GA29244@red-moon> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160929141520.GA29244@red-moon> 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: Lorenzo Pieralisi Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Marc Zyngier , Tomasz Nowicki , Will Deacon , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Sinan Kaya , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Jon Masters , Dennis Chen , Prem Mallappa List-Id: linux-acpi@vger.kernel.org On Thursday, September 29, 2016 03:15:20 PM Lorenzo Pieralisi wrote: > Hi Rafael, > > On Fri, Sep 09, 2016 at 03:23:30PM +0100, Lorenzo Pieralisi wrote: > > On systems booting with a device tree, every struct device is > > associated with a struct device_node, that represents its DT > > representation. The device node can be used in generic kernel > > contexts (eg IRQ translation, IOMMU streamid mapping), to > > retrieve the properties associated with the device and carry > > out kernel operation accordingly. Owing to the 1:1 relationship > > between the device and its device_node, the device_node can also > > be used as a look-up token for the device (eg looking up a device > > through its device_node), to retrieve the device in kernel paths > > where the device_node is available. > > > > On systems booting with ACPI, the same abstraction provided by > > the device_node is required to provide look-up functionality. > > > > Therefore, mirroring the approach implemented in the IRQ domain > > kernel layer, this patch adds an additional fwnode type FWNODE_IOMMU. > > > > This patch also implements a glue kernel layer that allows to > > allocate/free FWNODE_IOMMU fwnode_handle structures and associate > > them with IOMMU devices. > > > > Signed-off-by: Lorenzo Pieralisi > > Reviewed-by: Hanjun Guo > > Cc: Joerg Roedel > > Cc: "Rafael J. Wysocki" > > --- > > include/linux/fwnode.h | 1 + > > include/linux/iommu.h | 25 +++++++++++++++++++++++++ > > 2 files changed, 26 insertions(+) > > > > diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h > > index 8516717..6e10050 100644 > > --- a/include/linux/fwnode.h > > +++ b/include/linux/fwnode.h > > @@ -19,6 +19,7 @@ enum fwnode_type { > > FWNODE_ACPI_DATA, > > FWNODE_PDATA, > > FWNODE_IRQCHIP, > > + FWNODE_IOMMU, > > This patch provides groundwork for this series and it is key for > the rest of it, basically the point here is that we need a fwnode > to differentiate platform devices created out of static ACPI tables > entries (ie IORT), that represent IOMMU components. > > The corresponding device is not an ACPI device (I could fabricate one as > it is done for other static tables entries eg FADT power button, but I > do not necessarily see the reason for doing that given that all we need > the fwnode for is a token identifier), so FWNODE_ACPI does not apply > here. > > Please let me know if it is reasonable how I sorted this out (it > is basically identical to IRQCHIP, just another enum entry), the > remainder of the code depends on this. I'm not familiar with the use case, so I don't see anything unreasonable in it. If you're asking about whether or not I mind adding more fwnode types in principle, then no, I don't. :-) Thanks, Rafael From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934137AbcI2UxV (ORCPT ); Thu, 29 Sep 2016 16:53:21 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:46649 "HELO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933484AbcI2UxN (ORCPT ); Thu, 29 Sep 2016 16:53:13 -0400 From: "Rafael J. Wysocki" To: Lorenzo Pieralisi Cc: iommu@lists.linux-foundation.org, Joerg Roedel , Will Deacon , Marc Zyngier , Robin Murphy , Tomasz Nowicki , Hanjun Guo , Jon Masters , Eric Auger , Sinan Kaya , Nate Watterson , Prem Mallappa , Dennis Chen , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v5 01/14] drivers: iommu: add FWNODE_IOMMU fwnode type Date: Thu, 29 Sep 2016 22:59:40 +0200 Message-ID: <3178073.UTpgCTN6if@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.8.0-rc2+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <20160929141520.GA29244@red-moon> References: <20160909142343.13314-1-lorenzo.pieralisi@arm.com> <20160909142343.13314-2-lorenzo.pieralisi@arm.com> <20160929141520.GA29244@red-moon> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday, September 29, 2016 03:15:20 PM Lorenzo Pieralisi wrote: > Hi Rafael, > > On Fri, Sep 09, 2016 at 03:23:30PM +0100, Lorenzo Pieralisi wrote: > > On systems booting with a device tree, every struct device is > > associated with a struct device_node, that represents its DT > > representation. The device node can be used in generic kernel > > contexts (eg IRQ translation, IOMMU streamid mapping), to > > retrieve the properties associated with the device and carry > > out kernel operation accordingly. Owing to the 1:1 relationship > > between the device and its device_node, the device_node can also > > be used as a look-up token for the device (eg looking up a device > > through its device_node), to retrieve the device in kernel paths > > where the device_node is available. > > > > On systems booting with ACPI, the same abstraction provided by > > the device_node is required to provide look-up functionality. > > > > Therefore, mirroring the approach implemented in the IRQ domain > > kernel layer, this patch adds an additional fwnode type FWNODE_IOMMU. > > > > This patch also implements a glue kernel layer that allows to > > allocate/free FWNODE_IOMMU fwnode_handle structures and associate > > them with IOMMU devices. > > > > Signed-off-by: Lorenzo Pieralisi > > Reviewed-by: Hanjun Guo > > Cc: Joerg Roedel > > Cc: "Rafael J. Wysocki" > > --- > > include/linux/fwnode.h | 1 + > > include/linux/iommu.h | 25 +++++++++++++++++++++++++ > > 2 files changed, 26 insertions(+) > > > > diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h > > index 8516717..6e10050 100644 > > --- a/include/linux/fwnode.h > > +++ b/include/linux/fwnode.h > > @@ -19,6 +19,7 @@ enum fwnode_type { > > FWNODE_ACPI_DATA, > > FWNODE_PDATA, > > FWNODE_IRQCHIP, > > + FWNODE_IOMMU, > > This patch provides groundwork for this series and it is key for > the rest of it, basically the point here is that we need a fwnode > to differentiate platform devices created out of static ACPI tables > entries (ie IORT), that represent IOMMU components. > > The corresponding device is not an ACPI device (I could fabricate one as > it is done for other static tables entries eg FADT power button, but I > do not necessarily see the reason for doing that given that all we need > the fwnode for is a token identifier), so FWNODE_ACPI does not apply > here. > > Please let me know if it is reasonable how I sorted this out (it > is basically identical to IRQCHIP, just another enum entry), the > remainder of the code depends on this. I'm not familiar with the use case, so I don't see anything unreasonable in it. If you're asking about whether or not I mind adding more fwnode types in principle, then no, I don't. :-) Thanks, Rafael From mboxrd@z Thu Jan 1 00:00:00 1970 From: rjw@rjwysocki.net (Rafael J. Wysocki) Date: Thu, 29 Sep 2016 22:59:40 +0200 Subject: [PATCH v5 01/14] drivers: iommu: add FWNODE_IOMMU fwnode type In-Reply-To: <20160929141520.GA29244@red-moon> References: <20160909142343.13314-1-lorenzo.pieralisi@arm.com> <20160909142343.13314-2-lorenzo.pieralisi@arm.com> <20160929141520.GA29244@red-moon> Message-ID: <3178073.UTpgCTN6if@vostro.rjw.lan> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thursday, September 29, 2016 03:15:20 PM Lorenzo Pieralisi wrote: > Hi Rafael, > > On Fri, Sep 09, 2016 at 03:23:30PM +0100, Lorenzo Pieralisi wrote: > > On systems booting with a device tree, every struct device is > > associated with a struct device_node, that represents its DT > > representation. The device node can be used in generic kernel > > contexts (eg IRQ translation, IOMMU streamid mapping), to > > retrieve the properties associated with the device and carry > > out kernel operation accordingly. Owing to the 1:1 relationship > > between the device and its device_node, the device_node can also > > be used as a look-up token for the device (eg looking up a device > > through its device_node), to retrieve the device in kernel paths > > where the device_node is available. > > > > On systems booting with ACPI, the same abstraction provided by > > the device_node is required to provide look-up functionality. > > > > Therefore, mirroring the approach implemented in the IRQ domain > > kernel layer, this patch adds an additional fwnode type FWNODE_IOMMU. > > > > This patch also implements a glue kernel layer that allows to > > allocate/free FWNODE_IOMMU fwnode_handle structures and associate > > them with IOMMU devices. > > > > Signed-off-by: Lorenzo Pieralisi > > Reviewed-by: Hanjun Guo > > Cc: Joerg Roedel > > Cc: "Rafael J. Wysocki" > > --- > > include/linux/fwnode.h | 1 + > > include/linux/iommu.h | 25 +++++++++++++++++++++++++ > > 2 files changed, 26 insertions(+) > > > > diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h > > index 8516717..6e10050 100644 > > --- a/include/linux/fwnode.h > > +++ b/include/linux/fwnode.h > > @@ -19,6 +19,7 @@ enum fwnode_type { > > FWNODE_ACPI_DATA, > > FWNODE_PDATA, > > FWNODE_IRQCHIP, > > + FWNODE_IOMMU, > > This patch provides groundwork for this series and it is key for > the rest of it, basically the point here is that we need a fwnode > to differentiate platform devices created out of static ACPI tables > entries (ie IORT), that represent IOMMU components. > > The corresponding device is not an ACPI device (I could fabricate one as > it is done for other static tables entries eg FADT power button, but I > do not necessarily see the reason for doing that given that all we need > the fwnode for is a token identifier), so FWNODE_ACPI does not apply > here. > > Please let me know if it is reasonable how I sorted this out (it > is basically identical to IRQCHIP, just another enum entry), the > remainder of the code depends on this. I'm not familiar with the use case, so I don't see anything unreasonable in it. If you're asking about whether or not I mind adding more fwnode types in principle, then no, I don't. :-) Thanks, Rafael