Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754899Ab3IXX6T (ORCPT ); Tue, 24 Sep 2013 19:58:19 -0400 Received: from mail-yh0-f53.google.com ([209.85.213.53]:52844 "EHLO mail-yh0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754662Ab3IXX6Q (ORCPT ); Tue, 24 Sep 2013 19:58:16 -0400 Date: Tue, 24 Sep 2013 17:58:12 -0600 From: Bjorn Helgaas To: Bharat Bhushan Cc: alex.williamson@redhat.com, joro@8bytes.org, benh@kernel.crashing.org, galak@kernel.crashing.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org, agraf@suse.de, scottwood@freescale.com, iommu@lists.linux-foundation.org, Bharat Bhushan Subject: Re: [PATCH 1/7] powerpc: Add interface to get msi region information Message-ID: <20130924235812.GD9302@google.com> References: <1379575763-2091-1-git-send-email-Bharat.Bhushan@freescale.com> <1379575763-2091-2-git-send-email-Bharat.Bhushan@freescale.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1379575763-2091-2-git-send-email-Bharat.Bhushan@freescale.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5363 Lines: 162 On Thu, Sep 19, 2013 at 12:59:17PM +0530, Bharat Bhushan wrote: > This patch adds interface to get following information > - Number of MSI regions (which is number of MSI banks for powerpc). > - Get the region address range: Physical page which have the > address/addresses used for generating MSI interrupt > and size of the page. > > These are required to create IOMMU (Freescale PAMU) mapping for > devices which are directly assigned using VFIO. > > Signed-off-by: Bharat Bhushan > --- > arch/powerpc/include/asm/machdep.h | 8 +++++++ > arch/powerpc/include/asm/pci.h | 2 + > arch/powerpc/kernel/msi.c | 18 ++++++++++++++++ > arch/powerpc/sysdev/fsl_msi.c | 39 +++++++++++++++++++++++++++++++++-- > arch/powerpc/sysdev/fsl_msi.h | 11 ++++++++- > drivers/pci/msi.c | 26 ++++++++++++++++++++++++ > include/linux/msi.h | 8 +++++++ > include/linux/pci.h | 13 ++++++++++++ > 8 files changed, 120 insertions(+), 5 deletions(-) > > ... > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > index aca7578..6d85c15 100644 > --- a/drivers/pci/msi.c > +++ b/drivers/pci/msi.c > @@ -30,6 +30,20 @@ static int pci_msi_enable = 1; > > /* Arch hooks */ > > +#ifndef arch_msi_get_region_count > +int arch_msi_get_region_count(void) > +{ > + return 0; > +} > +#endif > + > +#ifndef arch_msi_get_region > +int arch_msi_get_region(int region_num, struct msi_region *region) > +{ > + return 0; > +} > +#endif This #define strategy is gone; see 4287d824 ("PCI: use weak functions for MSI arch-specific functions"). Please use the weak function strategy for your new MSI region functions. > + > #ifndef arch_msi_check_device > int arch_msi_check_device(struct pci_dev *dev, int nvec, int type) > { > @@ -903,6 +917,18 @@ void pci_disable_msi(struct pci_dev *dev) > } > EXPORT_SYMBOL(pci_disable_msi); > > +int msi_get_region_count(void) > +{ > + return arch_msi_get_region_count(); > +} > +EXPORT_SYMBOL(msi_get_region_count); > + > +int msi_get_region(int region_num, struct msi_region *region) > +{ > + return arch_msi_get_region(region_num, region); > +} > +EXPORT_SYMBOL(msi_get_region); Please split these interface additions, i.e., the drivers/pci/msi.c, include/linux/msi.h, and include/linux/pci.h changes, into a separate patch. I don't know enough about VFIO to understand why these new interfaces are needed. Is this the first VFIO IOMMU driver? I see vfio_iommu_spapr_tce.c and vfio_iommu_type1.c but I don't know if they're comparable to the Freescale PAMU. Do other VFIO IOMMU implementations support MSI? If so, do they handle the problem of mapping the MSI regions in a different way? > /** > * pci_msix_table_size - return the number of device's MSI-X table entries > * @dev: pointer to the pci_dev data structure of MSI-X device function > diff --git a/include/linux/msi.h b/include/linux/msi.h > index ee66f3a..ae32601 100644 > --- a/include/linux/msi.h > +++ b/include/linux/msi.h > @@ -50,6 +50,12 @@ struct msi_desc { > struct kobject kobj; > }; > > +struct msi_region { > + int region_num; > + dma_addr_t addr; > + size_t size; > +}; This needs some sort of explanatory comment. > /* > * The arch hook for setup up msi irqs > */ > @@ -58,5 +64,7 @@ void arch_teardown_msi_irq(unsigned int irq); > int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type); > void arch_teardown_msi_irqs(struct pci_dev *dev); > int arch_msi_check_device(struct pci_dev* dev, int nvec, int type); > +int arch_msi_get_region_count(void); > +int arch_msi_get_region(int region_num, struct msi_region *region); > > #endif /* LINUX_MSI_H */ > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 186540d..2b26a59 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1126,6 +1126,7 @@ struct msix_entry { > u16 entry; /* driver uses to specify entry, OS writes */ > }; > > +struct msi_region; > > #ifndef CONFIG_PCI_MSI > static inline int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec) > @@ -1168,6 +1169,16 @@ static inline int pci_msi_enabled(void) > { > return 0; > } > + > +static inline int msi_get_region_count(void) > +{ > + return 0; > +} > + > +static inline int msi_get_region(int region_num, struct msi_region *region) > +{ > + return 0; > +} > #else > int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec); > int pci_enable_msi_block_auto(struct pci_dev *dev, unsigned int *maxvec); > @@ -1180,6 +1191,8 @@ void pci_disable_msix(struct pci_dev *dev); > void msi_remove_pci_irq_vectors(struct pci_dev *dev); > void pci_restore_msi_state(struct pci_dev *dev); > int pci_msi_enabled(void); > +int msi_get_region_count(void); > +int msi_get_region(int region_num, struct msi_region *region); > #endif > > #ifdef CONFIG_PCIEPORTBUS > -- > 1.7.0.4 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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/