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 #include "pci.h" /* for pci_bar_index_is_valid() */ 13 14 /** 15 * pci_iomap_range - create a virtual mapping cookie for a PCI BAR 16 * @dev: PCI device that owns the BAR 17 * @bar: BAR number 18 * @offset: map memory at the given offset in BAR 19 * @maxlen: max length of the memory to map 20 * 21 * Using this function you will get a __iomem address to your device BAR. 22 * You can access it using ioread*() and iowrite*(). These functions hide 23 * the details if this is a MMIO or PIO address space and will just do what 24 * you expect from them in the correct way. 25 * 26 * @maxlen specifies the maximum length to map. If you want to get access to 27 * the complete BAR from offset to the end, pass %0 here. 28 * 29 * NOTE: 30 * This function is never managed, even if you initialized with 31 * pcim_enable_device(). 32 * */ 33 void __iomem *pci_iomap_range(struct pci_dev *dev, 34 int bar, 35 unsigned long offset, 36 unsigned long maxlen) 37 { 38 resource_size_t start, len; 39 unsigned long flags; 40 41 if (!pci_bar_index_is_valid(bar)) 42 return NULL; 43 44 start = pci_resource_start(dev, bar); 45 len = pci_resource_len(dev, bar); 46 flags = pci_resource_flags(dev, bar); 47 48 if (len <= offset || !start) 49 return NULL; 50 51 len -= offset; 52 start += offset; 53 if (maxlen && len > maxlen) 54 len = maxlen; 55 if (flags & IORESOURCE_IO) 56 return __pci_ioport_map(dev, start, len); 57 if (flags & IORESOURCE_MEM) 58 return ioremap(start, len); 59 /* What? */ 60 return NULL; 61 } 62 EXPORT_SYMBOL(pci_iomap_range); 63 64 /** 65 * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR 66 * @dev: PCI device that owns the BAR 67 * @bar: BAR number 68 * @offset: map memory at the given offset in BAR 69 * @maxlen: max length of the memory to map 70 * 71 * Using this function you will get a __iomem address to your device BAR. 72 * You can access it using ioread*() and iowrite*(). These functions hide 73 * the details if this is a MMIO or PIO address space and will just do what 74 * you expect from them in the correct way. When possible write combining 75 * is used. 76 * 77 * @maxlen specifies the maximum length to map. If you want to get access to 78 * the complete BAR from offset to the end, pass %0 here. 79 * 80 * NOTE: 81 * This function is never managed, even if you initialized with 82 * pcim_enable_device(). 83 * */ 84 void __iomem *pci_iomap_wc_range(struct pci_dev *dev, 85 int bar, 86 unsigned long offset, 87 unsigned long maxlen) 88 { 89 resource_size_t start, len; 90 unsigned long flags; 91 92 if (!pci_bar_index_is_valid(bar)) 93 return NULL; 94 95 start = pci_resource_start(dev, bar); 96 len = pci_resource_len(dev, bar); 97 flags = pci_resource_flags(dev, bar); 98 99 if (len <= offset || !start) 100 return NULL; 101 if (flags & IORESOURCE_IO) 102 return NULL; 103 104 len -= offset; 105 start += offset; 106 if (maxlen && len > maxlen) 107 len = maxlen; 108 109 if (flags & IORESOURCE_MEM) 110 return ioremap_wc(start, len); 111 112 /* What? */ 113 return NULL; 114 } 115 EXPORT_SYMBOL_GPL(pci_iomap_wc_range); 116 117 /** 118 * pci_iomap - create a virtual 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. 127 * 128 * @maxlen specifies the maximum length to map. If you want to get access to 129 * the complete BAR without checking for its length first, pass %0 here. 130 * 131 * NOTE: 132 * This function is never managed, even if you initialized with 133 * pcim_enable_device(). If you need automatic cleanup, use pcim_iomap(). 134 * */ 135 void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) 136 { 137 return pci_iomap_range(dev, bar, 0, maxlen); 138 } 139 EXPORT_SYMBOL(pci_iomap); 140 141 /** 142 * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR 143 * @dev: PCI device that owns the BAR 144 * @bar: BAR number 145 * @maxlen: length of the memory to map 146 * 147 * Using this function you will get a __iomem address to your device BAR. 148 * You can access it using ioread*() and iowrite*(). These functions hide 149 * the details if this is a MMIO or PIO address space and will just do what 150 * you expect from them in the correct way. When possible write combining 151 * is used. 152 * 153 * @maxlen specifies the maximum length to map. If you want to get access to 154 * the complete BAR without checking for its length first, pass %0 here. 155 * 156 * NOTE: 157 * This function is never managed, even if you initialized with 158 * pcim_enable_device(). 159 * */ 160 void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen) 161 { 162 return pci_iomap_wc_range(dev, bar, 0, maxlen); 163 } 164 EXPORT_SYMBOL_GPL(pci_iomap_wc); 165 166 /* 167 * pci_iounmap() somewhat illogically comes from lib/iomap.c for the 168 * CONFIG_GENERIC_IOMAP case, because that's the code that knows about 169 * the different IOMAP ranges. 170 * 171 * But if the architecture does not use the generic iomap code, and if 172 * it has _not_ defined its own private pci_iounmap function, we define 173 * it here. 174 * 175 * NOTE! This default implementation assumes that if the architecture 176 * support ioport mapping (HAS_IOPORT_MAP), the ioport mapping will 177 * be fixed to the range [ PCI_IOBASE, PCI_IOBASE+IO_SPACE_LIMIT [, 178 * and does not need unmapping with 'ioport_unmap()'. 179 * 180 * If you have different rules for your architecture, you need to 181 * implement your own pci_iounmap() that knows the rules for where 182 * and how IO vs MEM get mapped. 183 * 184 * This code is odd, and the ARCH_HAS/ARCH_WANTS #define logic comes 185 * from legacy <asm-generic/io.h> header file behavior. In particular, 186 * it would seem to make sense to do the iounmap(p) for the non-IO-space 187 * case here regardless, but that's not what the old header file code 188 * did. Probably incorrectly, but this is meant to be bug-for-bug 189 * compatible. 190 */ 191 #if defined(ARCH_WANTS_GENERIC_PCI_IOUNMAP) 192 193 void pci_iounmap(struct pci_dev *dev, void __iomem *p) 194 { 195 #ifdef ARCH_HAS_GENERIC_IOPORT_MAP 196 uintptr_t start = (uintptr_t) PCI_IOBASE; 197 uintptr_t addr = (uintptr_t) p; 198 199 if (addr >= start && addr < start + IO_SPACE_LIMIT) 200 return; 201 #endif 202 iounmap(p); 203 } 204 EXPORT_SYMBOL(pci_iounmap); 205 206 #endif /* ARCH_WANTS_GENERIC_PCI_IOUNMAP */ 207