Re: [PATCH 1/7] powerpc: Add interface to get msi region information
From: Bjorn Helgaas <bhelgaas@google.com>
Date: 2013-09-24 23:58:19
Also in:
linux-iommu, linux-pci, lkml
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 <redacted>
---
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(-)
...quoted hunk ↗ jump to hunk
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.
quoted hunk ↗ jump to hunk
+ #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?
quoted hunk ↗ jump to hunk
/** * 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 functiondiff --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.
quoted hunk ↗ jump to hunk
/* * 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