lib/iomap.c

   1 /*
   2  * Implement the default iomap interfaces
   3  *
   4  * (C) Copyright 2004 Linus Torvalds
   5  */
   6 #include <linux/pci.h>
   7 #include <linux/module.h>
   8 #include <asm/io.h>
   9
  10 /*
  11  * Read/write from/to an (offsettable) iomem cookie. It might be a PIO
  12  * access or a MMIO access, these functions don't care. The info is
  13  * encoded in the hardware mapping set up by the mapping functions
  14  * (or the cookie itself, depending on implementation and hw).
  15  *
  16  * The generic routines don't assume any hardware mappings, and just
  17  * encode the PIO/MMIO as part of the cookie. They coldly assume that
  18  * the MMIO IO mappings are not in the low address range.
  19  *
  20  * Architectures for which this is not true can't use this generic
  21  * implementation and should do their own copy.
  22  */
  23
  24 #ifndef HAVE_ARCH_PIO_SIZE
  25 /*
  26  * We encode the physical PIO addresses (0-0xffff) into the
  27  * pointer by offsetting them with a constant (0x10000) and
  28  * assuming that all the low addresses are always PIO. That means
  29  * we can do some sanity checks on the low bits, and don't
  30  * need to just take things for granted.
  31  */
  32 #define PIO_OFFSET      0x10000UL
  33 #define PIO_MASK        0x0ffffUL
  34 #define PIO_RESERVED    0x40000UL
  35 #endif
  36
  37 /*
  38  * Ugly macros are a way of life.
  39  */
  40 #define VERIFY_PIO(port) BUG_ON((port & ~PIO_MASK) != PIO_OFFSET)
  41
  42 #define IO_COND(addr, is_pio, is_mmio) do {                     \
  43         unsigned long port = (unsigned long __force)addr;       \
  44         if (port < PIO_RESERVED) {                              \
  45                 VERIFY_PIO(port);                               \
  46                 port &= PIO_MASK;                               \
  47                 is_pio;                                         \
  48         } else {                                                \
  49                 is_mmio;                                        \
  50         }                                                       \
  51 } while (0)
  52
  53 #ifndef pio_read16be
  54 #define pio_read16be(port) swab16(inw(port))
  55 #define pio_read32be(port) swab32(inl(port))
  56 #endif
  57
  58 #ifndef mmio_read16be
  59 #define mmio_read16be(addr) be16_to_cpu(__raw_readw(addr))
  60 #define mmio_read32be(addr) be32_to_cpu(__raw_readl(addr))
  61 #endif
  62
  63 unsigned int fastcall ioread8(void __iomem *addr)
  64 {
  65         IO_COND(addr, return inb(port), return readb(addr));
  66 }
  67 unsigned int fastcall ioread16(void __iomem *addr)
  68 {
  69         IO_COND(addr, return inw(port), return readw(addr));
  70 }
  71 unsigned int fastcall ioread16be(void __iomem *addr)
  72 {
  73         IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
  74 }
  75 unsigned int fastcall ioread32(void __iomem *addr)
  76 {
  77         IO_COND(addr, return inl(port), return readl(addr));
  78 }
  79 unsigned int fastcall ioread32be(void __iomem *addr)
  80 {
  81         IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
  82 }
  83 EXPORT_SYMBOL(ioread8);
  84 EXPORT_SYMBOL(ioread16);
  85 EXPORT_SYMBOL(ioread16be);
  86 EXPORT_SYMBOL(ioread32);
  87 EXPORT_SYMBOL(ioread32be);
  88
  89 #ifndef pio_write16be
  90 #define pio_write16be(val,port) outw(swab16(val),port)
  91 #define pio_write32be(val,port) outl(swab32(val),port)
  92 #endif
  93
  94 #ifndef mmio_write16be
  95 #define mmio_write16be(val,port) __raw_writew(be16_to_cpu(val),port)
  96 #define mmio_write32be(val,port) __raw_writel(be32_to_cpu(val),port)
  97 #endif
  98
  99 void fastcall iowrite8(u8 val, void __iomem *addr)
 100 {
 101         IO_COND(addr, outb(val,port), writeb(val, addr));
 102 }
 103 void fastcall iowrite16(u16 val, void __iomem *addr)
 104 {
 105         IO_COND(addr, outw(val,port), writew(val, addr));
 106 }
 107 void fastcall iowrite16be(u16 val, void __iomem *addr)
 108 {
 109         IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
 110 }
 111 void fastcall iowrite32(u32 val, void __iomem *addr)
 112 {
 113         IO_COND(addr, outl(val,port), writel(val, addr));
 114 }
 115 void fastcall iowrite32be(u32 val, void __iomem *addr)
 116 {
 117         IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
 118 }
 119 EXPORT_SYMBOL(iowrite8);
 120 EXPORT_SYMBOL(iowrite16);
 121 EXPORT_SYMBOL(iowrite16be);
 122 EXPORT_SYMBOL(iowrite32);
 123 EXPORT_SYMBOL(iowrite32be);
 124
 125 /*
 126  * These are the "repeat MMIO read/write" functions.
 127  * Note the "__raw" accesses, since we don't want to
 128  * convert to CPU byte order. We write in "IO byte
 129  * order" (we also don't have IO barriers).
 130  */
 131 #ifndef mmio_insb
 132 static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
 133 {
 134         while (--count >= 0) {
 135                 u8 data = __raw_readb(addr);
 136                 *dst = data;
 137                 dst++;
 138         }
 139 }
 140 static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
 141 {
 142         while (--count >= 0) {
 143                 u16 data = __raw_readw(addr);
 144                 *dst = data;
 145                 dst++;
 146         }
 147 }
 148 static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
 149 {
 150         while (--count >= 0) {
 151                 u32 data = __raw_readl(addr);
 152                 *dst = data;
 153                 dst++;
 154         }
 155 }
 156 #endif
 157
 158 #ifndef mmio_outsb
 159 static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
 160 {
 161         while (--count >= 0) {
 162                 __raw_writeb(*src, addr);
 163                 src++;
 164         }
 165 }
 166 static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
 167 {
 168         while (--count >= 0) {
 169                 __raw_writew(*src, addr);
 170                 src++;
 171         }
 172 }
 173 static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
 174 {
 175         while (--count >= 0) {
 176                 __raw_writel(*src, addr);
 177                 src++;
 178         }
 179 }
 180 #endif
 181
 182 void fastcall ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
 183 {
 184         IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
 185 }
 186 void fastcall ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
 187 {
 188         IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
 189 }
 190 void fastcall ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
 191 {
 192         IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
 193 }
 194 EXPORT_SYMBOL(ioread8_rep);
 195 EXPORT_SYMBOL(ioread16_rep);
 196 EXPORT_SYMBOL(ioread32_rep);
 197
 198 void fastcall iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
 199 {
 200         IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
 201 }
 202 void fastcall iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
 203 {
 204         IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
 205 }
 206 void fastcall iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
 207 {
 208         IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
 209 }
 210 EXPORT_SYMBOL(iowrite8_rep);
 211 EXPORT_SYMBOL(iowrite16_rep);
 212 EXPORT_SYMBOL(iowrite32_rep);
 213
 214 /* Create a virtual mapping cookie for an IO port range */
 215 void __iomem *ioport_map(unsigned long port, unsigned int nr)
 216 {
 217         if (port > PIO_MASK)
 218                 return NULL;
 219         return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
 220 }
 221
 222 void ioport_unmap(void __iomem *addr)
 223 {
 224         /* Nothing to do */
 225 }
 226 EXPORT_SYMBOL(ioport_map);
 227 EXPORT_SYMBOL(ioport_unmap);
 228
 229 /* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
 230 void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
 231 {
 232         unsigned long start = pci_resource_start(dev, bar);
 233         unsigned long len = pci_resource_len(dev, bar);
 234         unsigned long flags = pci_resource_flags(dev, bar);
 235
 236         if (!len || !start)
 237                 return NULL;
 238         if (maxlen && len > maxlen)
 239                 len = maxlen;
 240         if (flags & IORESOURCE_IO)
 241                 return ioport_map(start, len);
 242         if (flags & IORESOURCE_MEM) {
 243                 if (flags & IORESOURCE_CACHEABLE)
 244                         return ioremap(start, len);
 245                 return ioremap_nocache(start, len);
 246         }
 247         /* What? */
 248         return NULL;
 249 }
 250
 251 void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
 252 {
 253         IO_COND(addr, /* nothing */, iounmap(addr));
 254 }
 255 EXPORT_SYMBOL(pci_iomap);
 256 EXPORT_SYMBOL(pci_iounmap);