linux/arch/arm64/kernel/io.c

98 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Based on arch/arm/kernel/io.c
*
* Copyright (C) 2012 ARM Ltd.
*/
#include <linux/export.h>
#include <linux/types.h>
#include <linux/io.h>
/*
* Copy data from IO memory space to "real" memory space.
*/
void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
{
while (count && !IS_ALIGNED((unsigned long)from, 8)) {
*(u8 *)to = __raw_readb(from);
from++;
to++;
count--;
}
while (count >= 8) {
*(u64 *)to = __raw_readq(from);
from += 8;
to += 8;
count -= 8;
}
while (count) {
*(u8 *)to = __raw_readb(from);
from++;
to++;
count--;
}
}
EXPORT_SYMBOL(__memcpy_fromio);
/*
* Copy data from "real" memory space to IO memory space.
*/
void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
{
while (count && !IS_ALIGNED((unsigned long)to, 8)) {
__raw_writeb(*(u8 *)from, to);
from++;
to++;
count--;
}
while (count >= 8) {
__raw_writeq(*(u64 *)from, to);
from += 8;
to += 8;
count -= 8;
}
while (count) {
__raw_writeb(*(u8 *)from, to);
from++;
to++;
count--;
}
}
EXPORT_SYMBOL(__memcpy_toio);
/*
* "memset" on IO memory space.
*/
void __memset_io(volatile void __iomem *dst, int c, size_t count)
{
u64 qc = (u8)c;
qc |= qc << 8;
qc |= qc << 16;
qc |= qc << 32;
while (count && !IS_ALIGNED((unsigned long)dst, 8)) {
__raw_writeb(c, dst);
dst++;
count--;
}
while (count >= 8) {
__raw_writeq(qc, dst);
dst += 8;
count -= 8;
}
while (count) {
__raw_writeb(c, dst);
dst++;
count--;
}
}
EXPORT_SYMBOL(__memset_io);