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1// SPDX-License-Identifier: GPL-2.02/*3 * Implement the default iomap interfaces4 *5 * (C) Copyright 2004 Linus Torvalds6 */7#include <linux/pci.h>8#include <linux/io.h>9 10#include <linux/export.h>11 12/**13 * pci_iomap_range - create a virtual mapping cookie for a PCI BAR14 * @dev: PCI device that owns the BAR15 * @bar: BAR number16 * @offset: map memory at the given offset in BAR17 * @maxlen: max length of the memory to map18 *19 * Using this function you will get a __iomem address to your device BAR.20 * You can access it using ioread*() and iowrite*(). These functions hide21 * the details if this is a MMIO or PIO address space and will just do what22 * you expect from them in the correct way.23 *24 * @maxlen specifies the maximum length to map. If you want to get access to25 * the complete BAR from offset to the end, pass %0 here.26 *27 * NOTE:28 * This function is never managed, even if you initialized with29 * pcim_enable_device().30 * */31void __iomem *pci_iomap_range(struct pci_dev *dev,32 int bar,33 unsigned long offset,34 unsigned long maxlen)35{36 resource_size_t start = pci_resource_start(dev, bar);37 resource_size_t len = pci_resource_len(dev, bar);38 unsigned long flags = pci_resource_flags(dev, bar);39 40 if (len <= offset || !start)41 return NULL;42 len -= offset;43 start += offset;44 if (maxlen && len > maxlen)45 len = maxlen;46 if (flags & IORESOURCE_IO)47 return __pci_ioport_map(dev, start, len);48 if (flags & IORESOURCE_MEM)49 return ioremap(start, len);50 /* What? */51 return NULL;52}53EXPORT_SYMBOL(pci_iomap_range);54 55/**56 * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR57 * @dev: PCI device that owns the BAR58 * @bar: BAR number59 * @offset: map memory at the given offset in BAR60 * @maxlen: max length of the memory to map61 *62 * Using this function you will get a __iomem address to your device BAR.63 * You can access it using ioread*() and iowrite*(). These functions hide64 * the details if this is a MMIO or PIO address space and will just do what65 * you expect from them in the correct way. When possible write combining66 * is used.67 *68 * @maxlen specifies the maximum length to map. If you want to get access to69 * the complete BAR from offset to the end, pass %0 here.70 *71 * NOTE:72 * This function is never managed, even if you initialized with73 * pcim_enable_device().74 * */75void __iomem *pci_iomap_wc_range(struct pci_dev *dev,76 int bar,77 unsigned long offset,78 unsigned long maxlen)79{80 resource_size_t start = pci_resource_start(dev, bar);81 resource_size_t len = pci_resource_len(dev, bar);82 unsigned long flags = pci_resource_flags(dev, bar);83 84 85 if (flags & IORESOURCE_IO)86 return NULL;87 88 if (len <= offset || !start)89 return NULL;90 91 len -= offset;92 start += offset;93 if (maxlen && len > maxlen)94 len = maxlen;95 96 if (flags & IORESOURCE_MEM)97 return ioremap_wc(start, len);98 99 /* What? */100 return NULL;101}102EXPORT_SYMBOL_GPL(pci_iomap_wc_range);103 104/**105 * pci_iomap - create a virtual mapping cookie for a PCI BAR106 * @dev: PCI device that owns the BAR107 * @bar: BAR number108 * @maxlen: length of the memory to map109 *110 * Using this function you will get a __iomem address to your device BAR.111 * You can access it using ioread*() and iowrite*(). These functions hide112 * the details if this is a MMIO or PIO address space and will just do what113 * you expect from them in the correct way.114 *115 * @maxlen specifies the maximum length to map. If you want to get access to116 * the complete BAR without checking for its length first, pass %0 here.117 *118 * NOTE:119 * This function is never managed, even if you initialized with120 * pcim_enable_device(). If you need automatic cleanup, use pcim_iomap().121 * */122void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)123{124 return pci_iomap_range(dev, bar, 0, maxlen);125}126EXPORT_SYMBOL(pci_iomap);127 128/**129 * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR130 * @dev: PCI device that owns the BAR131 * @bar: BAR number132 * @maxlen: length of the memory to map133 *134 * Using this function you will get a __iomem address to your device BAR.135 * You can access it using ioread*() and iowrite*(). These functions hide136 * the details if this is a MMIO or PIO address space and will just do what137 * you expect from them in the correct way. When possible write combining138 * is used.139 *140 * @maxlen specifies the maximum length to map. If you want to get access to141 * the complete BAR without checking for its length first, pass %0 here.142 *143 * NOTE:144 * This function is never managed, even if you initialized with145 * pcim_enable_device().146 * */147void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)148{149 return pci_iomap_wc_range(dev, bar, 0, maxlen);150}151EXPORT_SYMBOL_GPL(pci_iomap_wc);152 153/*154 * pci_iounmap() somewhat illogically comes from lib/iomap.c for the155 * CONFIG_GENERIC_IOMAP case, because that's the code that knows about156 * the different IOMAP ranges.157 *158 * But if the architecture does not use the generic iomap code, and if159 * it has _not_ defined its own private pci_iounmap function, we define160 * it here.161 *162 * NOTE! This default implementation assumes that if the architecture163 * support ioport mapping (HAS_IOPORT_MAP), the ioport mapping will164 * be fixed to the range [ PCI_IOBASE, PCI_IOBASE+IO_SPACE_LIMIT [,165 * and does not need unmapping with 'ioport_unmap()'.166 *167 * If you have different rules for your architecture, you need to168 * implement your own pci_iounmap() that knows the rules for where169 * and how IO vs MEM get mapped.170 *171 * This code is odd, and the ARCH_HAS/ARCH_WANTS #define logic comes172 * from legacy <asm-generic/io.h> header file behavior. In particular,173 * it would seem to make sense to do the iounmap(p) for the non-IO-space174 * case here regardless, but that's not what the old header file code175 * did. Probably incorrectly, but this is meant to be bug-for-bug176 * compatible.177 */178#if defined(ARCH_WANTS_GENERIC_PCI_IOUNMAP)179 180void pci_iounmap(struct pci_dev *dev, void __iomem *p)181{182#ifdef ARCH_HAS_GENERIC_IOPORT_MAP183 uintptr_t start = (uintptr_t) PCI_IOBASE;184 uintptr_t addr = (uintptr_t) p;185 186 if (addr >= start && addr < start + IO_SPACE_LIMIT)187 return;188#endif189 iounmap(p);190}191EXPORT_SYMBOL(pci_iounmap);192 193#endif /* ARCH_WANTS_GENERIC_PCI_IOUNMAP */194