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1 : // SPDX-License-Identifier: GPL-2.0 2 : /* 3 : * Implement the default iomap interfaces 4 : * 5 : * (C) Copyright 2004 Linus Torvalds 6 : */ 7 : #include <linux/pci.h> 8 : #include <linux/io.h> 9 : 10 : #include <linux/export.h> 11 : 12 : #ifdef CONFIG_PCI 13 : /** 14 : * pci_iomap_range - create a virtual mapping cookie for a PCI BAR 15 : * @dev: PCI device that owns the BAR 16 : * @bar: BAR number 17 : * @offset: map memory at the given offset in BAR 18 : * @maxlen: max length of the memory to map 19 : * 20 : * Using this function you will get a __iomem address to your device BAR. 21 : * You can access it using ioread*() and iowrite*(). These functions hide 22 : * the details if this is a MMIO or PIO address space and will just do what 23 : * you expect from them in the correct way. 24 : * 25 : * @maxlen specifies the maximum length to map. If you want to get access to 26 : * the complete BAR from offset to the end, pass %0 here. 27 : * */ 28 0 : void __iomem *pci_iomap_range(struct pci_dev *dev, 29 : int bar, 30 : unsigned long offset, 31 : unsigned long maxlen) 32 : { 33 0 : resource_size_t start = pci_resource_start(dev, bar); 34 0 : resource_size_t len = pci_resource_len(dev, bar); 35 0 : unsigned long flags = pci_resource_flags(dev, bar); 36 : 37 0 : if (len <= offset || !start) 38 : return NULL; 39 0 : len -= offset; 40 0 : start += offset; 41 0 : if (maxlen && len > maxlen) 42 0 : len = maxlen; 43 0 : if (flags & IORESOURCE_IO) 44 0 : return __pci_ioport_map(dev, start, len); 45 0 : if (flags & IORESOURCE_MEM) 46 0 : return ioremap(start, len); 47 : /* What? */ 48 : return NULL; 49 : } 50 : EXPORT_SYMBOL(pci_iomap_range); 51 : 52 : /** 53 : * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR 54 : * @dev: PCI device that owns the BAR 55 : * @bar: BAR number 56 : * @offset: map memory at the given offset in BAR 57 : * @maxlen: max length of the memory to map 58 : * 59 : * Using this function you will get a __iomem address to your device BAR. 60 : * You can access it using ioread*() and iowrite*(). These functions hide 61 : * the details if this is a MMIO or PIO address space and will just do what 62 : * you expect from them in the correct way. When possible write combining 63 : * is used. 64 : * 65 : * @maxlen specifies the maximum length to map. If you want to get access to 66 : * the complete BAR from offset to the end, pass %0 here. 67 : * */ 68 0 : void __iomem *pci_iomap_wc_range(struct pci_dev *dev, 69 : int bar, 70 : unsigned long offset, 71 : unsigned long maxlen) 72 : { 73 0 : resource_size_t start = pci_resource_start(dev, bar); 74 0 : resource_size_t len = pci_resource_len(dev, bar); 75 0 : unsigned long flags = pci_resource_flags(dev, bar); 76 : 77 : 78 0 : if (flags & IORESOURCE_IO) 79 : return NULL; 80 : 81 0 : if (len <= offset || !start) 82 : return NULL; 83 : 84 0 : len -= offset; 85 0 : start += offset; 86 0 : if (maxlen && len > maxlen) 87 0 : len = maxlen; 88 : 89 0 : if (flags & IORESOURCE_MEM) 90 0 : return ioremap_wc(start, len); 91 : 92 : /* What? */ 93 : return NULL; 94 : } 95 : EXPORT_SYMBOL_GPL(pci_iomap_wc_range); 96 : 97 : /** 98 : * pci_iomap - create a virtual mapping cookie for a PCI BAR 99 : * @dev: PCI device that owns the BAR 100 : * @bar: BAR number 101 : * @maxlen: length of the memory to map 102 : * 103 : * Using this function you will get a __iomem address to your device BAR. 104 : * You can access it using ioread*() and iowrite*(). These functions hide 105 : * the details if this is a MMIO or PIO address space and will just do what 106 : * you expect from them in the correct way. 107 : * 108 : * @maxlen specifies the maximum length to map. If you want to get access to 109 : * the complete BAR without checking for its length first, pass %0 here. 110 : * */ 111 0 : void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) 112 : { 113 0 : return pci_iomap_range(dev, bar, 0, maxlen); 114 : } 115 : EXPORT_SYMBOL(pci_iomap); 116 : 117 : /** 118 : * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR 119 : * @dev: PCI device that owns the BAR 120 : * @bar: BAR number 121 : * @maxlen: length of the memory to map 122 : * 123 : * Using this function you will get a __iomem address to your device BAR. 124 : * You can access it using ioread*() and iowrite*(). These functions hide 125 : * the details if this is a MMIO or PIO address space and will just do what 126 : * you expect from them in the correct way. When possible write combining 127 : * is used. 128 : * 129 : * @maxlen specifies the maximum length to map. If you want to get access to 130 : * the complete BAR without checking for its length first, pass %0 here. 131 : * */ 132 0 : void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen) 133 : { 134 0 : return pci_iomap_wc_range(dev, bar, 0, maxlen); 135 : } 136 : EXPORT_SYMBOL_GPL(pci_iomap_wc); 137 : 138 : /* 139 : * pci_iounmap() somewhat illogically comes from lib/iomap.c for the 140 : * CONFIG_GENERIC_IOMAP case, because that's the code that knows about 141 : * the different IOMAP ranges. 142 : * 143 : * But if the architecture does not use the generic iomap code, and if 144 : * it has _not_ defined it's own private pci_iounmap function, we define 145 : * it here. 146 : * 147 : * NOTE! This default implementation assumes that if the architecture 148 : * support ioport mapping (HAS_IOPORT_MAP), the ioport mapping will 149 : * be fixed to the range [ PCI_IOBASE, PCI_IOBASE+IO_SPACE_LIMIT [, 150 : * and does not need unmapping with 'ioport_unmap()'. 151 : * 152 : * If you have different rules for your architecture, you need to 153 : * implement your own pci_iounmap() that knows the rules for where 154 : * and how IO vs MEM get mapped. 155 : * 156 : * This code is odd, and the ARCH_HAS/ARCH_WANTS #define logic comes 157 : * from legacy <asm-generic/io.h> header file behavior. In particular, 158 : * it would seem to make sense to do the iounmap(p) for the non-IO-space 159 : * case here regardless, but that's not what the old header file code 160 : * did. Probably incorrectly, but this is meant to be bug-for-bug 161 : * compatible. 162 : */ 163 : #if defined(ARCH_WANTS_GENERIC_PCI_IOUNMAP) 164 : 165 : void pci_iounmap(struct pci_dev *dev, void __iomem *p) 166 : { 167 : #ifdef ARCH_HAS_GENERIC_IOPORT_MAP 168 : uintptr_t start = (uintptr_t) PCI_IOBASE; 169 : uintptr_t addr = (uintptr_t) p; 170 : 171 : if (addr >= start && addr < start + IO_SPACE_LIMIT) 172 : return; 173 : iounmap(p); 174 : #endif 175 : } 176 : EXPORT_SYMBOL(pci_iounmap); 177 : 178 : #endif /* ARCH_WANTS_GENERIC_PCI_IOUNMAP */ 179 : 180 : #endif /* CONFIG_PCI */