| 1 | /******************************************************************************* |
| 2 | for Alpha Linux |
| 3 | *******************************************************************************/ |
| 4 | |
| 5 | /* |
| 6 | * Create a dependency that should be immune from the effect of register |
| 7 | * renaming as is commonly seen in superscalar processors. This should |
| 8 | * insert a minimum of 100-ns delays between reads/writes at clock rates |
| 9 | * up to 100 MHz---GGL |
| 10 | * |
| 11 | * Slowbcopy(char *src, char *dst, int count) |
| 12 | * |
| 13 | */ |
| 14 | |
| 15 | #ifdef HAVE_XORG_CONFIG_H |
| 16 | #include <xorg-config.h> |
| 17 | #endif |
| 18 | |
| 19 | #include <X11/X.h> |
| 20 | #include "xf86.h" |
| 21 | #include "xf86Priv.h" |
| 22 | #include "xf86_OSlib.h" |
| 23 | #include "compiler.h" |
| 24 | |
| 25 | static int really_slow_bcopy; |
| 26 | |
| 27 | void |
| 28 | xf86SetReallySlowBcopy(void) |
| 29 | { |
| 30 | really_slow_bcopy = 1; |
| 31 | } |
| 32 | |
| 33 | #if defined(__i386__) || defined(__amd64__) |
| 34 | static void |
| 35 | xf86_really_slow_bcopy(unsigned char *src, unsigned char *dst, int len) |
| 36 | { |
| 37 | while (len--) { |
| 38 | *dst++ = *src++; |
| 39 | outb(0x80, 0x00); |
| 40 | } |
| 41 | } |
| 42 | #endif |
| 43 | |
| 44 | /* The outb() isn't needed on my machine, but who knows ... -- ost */ |
| 45 | void |
| 46 | xf86SlowBcopy(unsigned char *src, unsigned char *dst, int len) |
| 47 | { |
| 48 | #if defined(__i386__) || defined(__amd64__) |
| 49 | if (really_slow_bcopy) { |
| 50 | xf86_really_slow_bcopy(src, dst, len); |
| 51 | return; |
| 52 | } |
| 53 | #endif |
| 54 | while (len--) |
| 55 | *dst++ = *src++; |
| 56 | } |
| 57 | |
| 58 | #ifdef __alpha__ |
| 59 | |
| 60 | #ifdef linux |
| 61 | |
| 62 | unsigned long _bus_base(void); |
| 63 | |
| 64 | #define useSparse() (!_bus_base()) |
| 65 | |
| 66 | #define SPARSE (7) |
| 67 | |
| 68 | #else |
| 69 | |
| 70 | #define useSparse() 0 |
| 71 | |
| 72 | #define SPARSE 0 |
| 73 | |
| 74 | #endif |
| 75 | |
| 76 | void |
| 77 | xf86SlowBCopyFromBus(unsigned char *src, unsigned char *dst, int count) |
| 78 | { |
| 79 | if (useSparse()) { |
| 80 | unsigned long addr; |
| 81 | long result; |
| 82 | |
| 83 | addr = (unsigned long) src; |
| 84 | while (count) { |
| 85 | result = *(volatile int *) addr; |
| 86 | result >>= ((addr >> SPARSE) & 3) * 8; |
| 87 | *dst++ = (unsigned char) (0xffUL & result); |
| 88 | addr += 1 << SPARSE; |
| 89 | count--; |
| 90 | outb(0x80, 0x00); |
| 91 | } |
| 92 | } |
| 93 | else |
| 94 | xf86SlowBcopy(src, dst, count); |
| 95 | } |
| 96 | |
| 97 | void |
| 98 | xf86SlowBCopyToBus(unsigned char *src, unsigned char *dst, int count) |
| 99 | { |
| 100 | if (useSparse()) { |
| 101 | unsigned long addr; |
| 102 | |
| 103 | addr = (unsigned long) dst; |
| 104 | while (count) { |
| 105 | *(volatile unsigned int *) addr = |
| 106 | (unsigned short) (*src) * 0x01010101; |
| 107 | src++; |
| 108 | addr += 1 << SPARSE; |
| 109 | count--; |
| 110 | outb(0x80, 0x00); |
| 111 | } |
| 112 | } |
| 113 | else |
| 114 | xf86SlowBcopy(src, dst, count); |
| 115 | } |
| 116 | #endif |