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