From ad78e05d654567e0a96f91d5db198469ddc2d4fb Mon Sep 17 00:00:00 2001 From: Philipp Stanner Date: Thu, 13 Jun 2024 13:50:25 +0200 Subject: [PATCH] PCI: Add managed pcim_iomap_range() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The only managed mapping function currently is pcim_iomap() which doesn't allow for mapping an area starting at a certain offset, which many drivers want. Add pcim_iomap_range() as an exported function. Link: https://lore.kernel.org/r/20240613115032.29098-13-pstanner@redhat.com Signed-off-by: Philipp Stanner Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas --- drivers/pci/devres.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 46 insertions(+) diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c index f4a0af2c4d79..3780a9f9ec00 100644 --- a/drivers/pci/devres.c +++ b/drivers/pci/devres.c @@ -1027,3 +1027,47 @@ void pcim_iounmap_regions(struct pci_dev *pdev, int mask) } } EXPORT_SYMBOL(pcim_iounmap_regions); + +/** + * pcim_iomap_range - Create a ranged __iomap mapping within a PCI BAR + * @pdev: PCI device to map IO resources for + * @bar: Index of the BAR + * @offset: Offset from the begin of the BAR + * @len: Length in bytes for the mapping + * + * Returns: __iomem pointer on success, an IOMEM_ERR_PTR on failure. + * + * Creates a new IO-Mapping within the specified @bar, ranging from @offset to + * @offset + @len. + * + * The mapping will automatically get unmapped on driver detach. If desired, + * release manually only with pcim_iounmap(). + */ +void __iomem *pcim_iomap_range(struct pci_dev *pdev, int bar, + unsigned long offset, unsigned long len) +{ + void __iomem *mapping; + struct pcim_addr_devres *res; + + res = pcim_addr_devres_alloc(pdev); + if (!res) + return IOMEM_ERR_PTR(-ENOMEM); + + mapping = pci_iomap_range(pdev, bar, offset, len); + if (!mapping) { + pcim_addr_devres_free(res); + return IOMEM_ERR_PTR(-EINVAL); + } + + res->type = PCIM_ADDR_DEVRES_TYPE_MAPPING; + res->baseaddr = mapping; + + /* + * Ranged mappings don't get added to the legacy-table, since the table + * only ever keeps track of whole BARs. + */ + + devres_add(&pdev->dev, res); + return mapping; +} +EXPORT_SYMBOL(pcim_iomap_range); diff --git a/include/linux/pci.h b/include/linux/pci.h index 0c19f0717899..98893a89bb5b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2303,6 +2303,8 @@ int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name); int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask, const char *name); void pcim_iounmap_regions(struct pci_dev *pdev, int mask); +void __iomem *pcim_iomap_range(struct pci_dev *pdev, int bar, + unsigned long offset, unsigned long len); extern int pci_pci_problems; #define PCIPCI_FAIL 1 /* No PCI PCI DMA */ -- 2.25.1