xserver-multidpi/hw/xfree86/os-support/misc/SlowBcopy.c
Matt Turner 9625f6d328 Fix breakage on alpha caused by c7680befe5
Pinpointed by by Michael Cree.

Commit c7680befe5 removed Jensen support, but at the same time broke
support for dense memory systems.

Signed-off-by: Matt Turner <mattst88@gmail.com>
2009-10-06 20:58:30 -04:00

118 lines
2.2 KiB
C

/*******************************************************************************
for Alpha Linux
*******************************************************************************/
/*
* Create a dependency that should be immune from the effect of register
* renaming as is commonly seen in superscalar processors. This should
* insert a minimum of 100-ns delays between reads/writes at clock rates
* up to 100 MHz---GGL
*
* Slowbcopy(char *src, char *dst, int count)
*
*/
#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif
#include <X11/X.h>
#include "xf86.h"
#include "xf86Priv.h"
#include "xf86_OSlib.h"
#include "compiler.h"
static int really_slow_bcopy;
void
xf86SetReallySlowBcopy(void)
{
really_slow_bcopy = 1;
}
#if defined(__i386__) || defined(__amd64__)
static void xf86_really_slow_bcopy(unsigned char *src, unsigned char *dst, int len)
{
while(len--)
{
*dst++ = *src++;
outb(0x80, 0x00);
}
}
#endif
/* The outb() isn't needed on my machine, but who knows ... -- ost */
void
xf86SlowBcopy(unsigned char *src, unsigned char *dst, int len)
{
#if defined(__i386__) || defined(__amd64__)
if (really_slow_bcopy) {
xf86_really_slow_bcopy(src, dst, len);
return;
}
#endif
while(len--)
*dst++ = *src++;
}
#ifdef __alpha__
#ifdef linux
unsigned long _bus_base(void);
#define useSparse() (!_bus_base())
#define SPARSE (7)
#else
#define useSparse() 0
#define SPARSE 0
#endif
void
xf86SlowBCopyFromBus(unsigned char *src, unsigned char *dst, int count)
{
if (useSparse())
{
unsigned long addr;
long result;
addr = (unsigned long) src;
while (count) {
result = *(volatile int *) addr;
result >>= ((addr>>SPARSE) & 3) * 8;
*dst++ = (unsigned char) (0xffUL & result);
addr += 1<<SPARSE;
count--;
outb(0x80, 0x00);
}
}
else
xf86SlowBcopy(src, dst, count);
}
void
xf86SlowBCopyToBus(unsigned char *src, unsigned char *dst, int count)
{
if (useSparse())
{
unsigned long addr;
addr = (unsigned long) dst;
while (count) {
*(volatile unsigned int *) addr = (unsigned short)(*src) * 0x01010101;
src++;
addr += 1<<SPARSE;
count--;
outb(0x80, 0x00);
}
}
else
xf86SlowBcopy(src, dst, count);
}
#endif