linux/arch/sh/kernel/io.c
Paul Mundt 86e4dd5add sh: support for platforms without PIO.
This extends some of the existing special casing for HAS_IOPORT
platforms and gets it to the point where platforms can begin to
conditionally select it.

The major changes here are that the PIO routines themselves go away
completely, including all of the machvec port mapping wrappers. With this
in place it's possible for any non-machvec abusing platform to disable
PIO completely. At present this is left as an opt-in until the abusers
are the odd ones out instead of the majority.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-06-02 16:31:42 +09:00

114 lines
2.6 KiB
C

/*
* arch/sh/kernel/io.c - Machine independent I/O functions.
*
* Copyright (C) 2000 - 2009 Stuart Menefy
* Copyright (C) 2005 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <asm/machvec.h>
#include <asm/io.h>
/*
* Copy data from IO memory space to "real" memory space.
*/
void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)
{
/*
* Would it be worthwhile doing byte and long transfers first
* to try and get aligned?
*/
#ifdef CONFIG_CPU_SH4
if ((count >= 0x20) &&
(((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {
int tmp2, tmp3, tmp4, tmp5, tmp6;
__asm__ __volatile__(
"1: \n\t"
"mov.l @%7+, r0 \n\t"
"mov.l @%7+, %2 \n\t"
"movca.l r0, @%0 \n\t"
"mov.l @%7+, %3 \n\t"
"mov.l @%7+, %4 \n\t"
"mov.l @%7+, %5 \n\t"
"mov.l @%7+, %6 \n\t"
"mov.l @%7+, r7 \n\t"
"mov.l @%7+, r0 \n\t"
"mov.l %2, @(0x04,%0) \n\t"
"mov #0x20, %2 \n\t"
"mov.l %3, @(0x08,%0) \n\t"
"sub %2, %1 \n\t"
"mov.l %4, @(0x0c,%0) \n\t"
"cmp/hi %1, %2 ! T if 32 > count \n\t"
"mov.l %5, @(0x10,%0) \n\t"
"mov.l %6, @(0x14,%0) \n\t"
"mov.l r7, @(0x18,%0) \n\t"
"mov.l r0, @(0x1c,%0) \n\t"
"bf.s 1b \n\t"
" add #0x20, %0 \n\t"
: "=&r" (to), "=&r" (count),
"=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),
"=&r" (tmp5), "=&r" (tmp6), "=&r" (from)
: "7"(from), "0" (to), "1" (count)
: "r0", "r7", "t", "memory");
}
#endif
if ((((u32)to | (u32)from) & 0x3) == 0) {
for (; count > 3; count -= 4) {
*(u32 *)to = *(volatile u32 *)from;
to += 4;
from += 4;
}
}
for (; count > 0; count--) {
*(u8 *)to = *(volatile u8 *)from;
to++;
from++;
}
mb();
}
EXPORT_SYMBOL(memcpy_fromio);
/*
* Copy data from "real" memory space to IO memory space.
*/
void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)
{
if ((((u32)to | (u32)from) & 0x3) == 0) {
for ( ; count > 3; count -= 4) {
*(volatile u32 *)to = *(u32 *)from;
to += 4;
from += 4;
}
}
for (; count > 0; count--) {
*(volatile u8 *)to = *(u8 *)from;
to++;
from++;
}
mb();
}
EXPORT_SYMBOL(memcpy_toio);
/*
* "memset" on IO memory space.
* This needs to be optimized.
*/
void memset_io(volatile void __iomem *dst, int c, unsigned long count)
{
while (count) {
count--;
writeb(c, dst);
dst++;
}
}
EXPORT_SYMBOL(memset_io);