From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754058AbaIHN4Z (ORCPT ); Mon, 8 Sep 2014 09:56:25 -0400 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21]:53526 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753034AbaIHN4W (ORCPT ); Mon, 8 Sep 2014 09:56:22 -0400 From: Liviu Dudau To: Bjorn Helgaas , Arnd Bergmann , Rob Herring , Jason Gunthorpe , Benjamin Herrenschmidt , Catalin Marinas , Will Deacon , Russell King , linux-pci , Linus Walleij Cc: Tanmay Inamdar , Grant Likely , Sinan Kaya , Jingoo Han , Kukjin Kim , Suravee Suthikulanit , linux-arch , LKML , Device Tree ML , LAKML Subject: [PATCH v10 10/10] PCI: Introduce pci_remap_iospace() for remapping PCI I/O bus resources into CPU space Date: Mon, 8 Sep 2014 14:54:32 +0100 Message-Id: <1410184472-17630-11-git-send-email-Liviu.Dudau@arm.com> X-Mailer: git-send-email 2.0.4 In-Reply-To: <1410184472-17630-1-git-send-email-Liviu.Dudau@arm.com> References: <1410184472-17630-1-git-send-email-Liviu.Dudau@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce a default implementation for remapping PCI bus I/O resources onto the CPU address space. Architectures with special needs may provide their own version, but most should be able to use this one. Cc: Bjorn Helgaas Cc: Arnd Bergmann Cc: Rob Herring Reviewed-by: Catalin Marinas Signed-off-by: Liviu Dudau --- drivers/pci/pci.c | 33 +++++++++++++++++++++++++++++++++ include/asm-generic/pgtable.h | 4 ++++ include/linux/pci.h | 3 +++ 3 files changed, 40 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 2c9ac70..654b44c 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2704,6 +2704,39 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name) } EXPORT_SYMBOL(pci_request_regions_exclusive); +/** + * pci_remap_iospace - Remap the memory mapped I/O space + * @res: Resource describing the I/O space + * @phys_addr: physical address where the range will be mapped. + * + * Remap the memory mapped I/O space described by the @res + * into the CPU physical address space. Only architectures + * that have memory mapped IO defined (and hence PCI_IOBASE) + * should call this function. + */ +int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr) +{ + int err = -ENODEV; + +#ifdef PCI_IOBASE + if (!(res->flags & IORESOURCE_IO)) + return -EINVAL; + + if (res->end > IO_SPACE_LIMIT) + return -EINVAL; + + err = ioremap_page_range(res->start + (unsigned long)PCI_IOBASE, + res->end + 1 + (unsigned long)PCI_IOBASE, + phys_addr, pgprot_device(PAGE_KERNEL)); +#else + /* this architecture does not have memory mapped I/O space, + so this function should never be called */ + WARN_ON(1); +#endif + + return err; +} + static void __pci_set_master(struct pci_dev *dev, bool enable) { u16 old_cmd, cmd; diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 53b2acc..977e545 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -249,6 +249,10 @@ static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) #define pgprot_writecombine pgprot_noncached #endif +#ifndef pgprot_device +#define pgprot_device pgprot_noncached +#endif + /* * When walking page tables, get the address of the next boundary, * or the end address of the range if that comes earlier. Although no diff --git a/include/linux/pci.h b/include/linux/pci.h index a494e5d..fc8c529 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1100,6 +1100,9 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus, resource_size_t), void *alignf_data); + +int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr); + static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar) { struct pci_bus_region region; -- 2.0.4