// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * I/O string operations
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *    Copyright (C) 2006 IBM Corporation
 *
 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
 * and Paul Mackerras.
 *
 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
 *
 * Rewritten in C by Stephen Rothwell.
 */
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/export.h>

#include <asm/io.h>
#include <asm/firmware.h>
#include <asm/bug.h>

/* See definition in io.h */
bool isa_io_special;

void _insb(const volatile u8 __iomem *port, void *buf, long count)
{
        u8 *tbuf = buf;
        u8 tmp;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                tmp = *(const volatile u8 __force *)port;
                eieio();
                *tbuf++ = tmp;
        } while (--count != 0);
        data_barrier(tmp);
}
EXPORT_SYMBOL(_insb);

void _outsb(volatile u8 __iomem *port, const void *buf, long count)
{
        const u8 *tbuf = buf;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                *(volatile u8 __force *)port = *tbuf++;
        } while (--count != 0);
        mb();
}
EXPORT_SYMBOL(_outsb);

void _insw(const volatile u16 __iomem *port, void *buf, long count)
{
        u16 *tbuf = buf;
        u16 tmp;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                tmp = *(const volatile u16 __force *)port;
                eieio();
                *tbuf++ = tmp;
        } while (--count != 0);
        data_barrier(tmp);
}
EXPORT_SYMBOL(_insw);

void _outsw(volatile u16 __iomem *port, const void *buf, long count)
{
        const u16 *tbuf = buf;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                *(volatile u16 __force *)port = *tbuf++;
        } while (--count != 0);
        mb();
}
EXPORT_SYMBOL(_outsw);

void _insl(const volatile u32 __iomem *port, void *buf, long count)
{
        u32 *tbuf = buf;
        u32 tmp;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                tmp = *(const volatile u32 __force *)port;
                eieio();
                *tbuf++ = tmp;
        } while (--count != 0);
        data_barrier(tmp);
}
EXPORT_SYMBOL(_insl);

void _outsl(volatile u32 __iomem *port, const void *buf, long count)
{
        const u32 *tbuf = buf;

        if (unlikely(count <= 0))
                return;

        mb();
        do {
                *(volatile u32 __force *)port = *tbuf++;
        } while (--count != 0);
        mb();
}
EXPORT_SYMBOL(_outsl);

#define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)

notrace void
_memset_io(volatile void __iomem *addr, int c, unsigned long n)
{
        void *p = (void __force *)addr;
        u32 lc = c;
        lc |= lc << 8;
        lc |= lc << 16;

        mb();
        while(n && !IO_CHECK_ALIGN(p, 4)) {
                *((volatile u8 *)p) = c;
                p++;
                n--;
        }
        while(n >= 4) {
                *((volatile u32 *)p) = lc;
                p += 4;
                n -= 4;
        }
        while(n) {
                *((volatile u8 *)p) = c;
                p++;
                n--;
        }
        mb();
}
EXPORT_SYMBOL(_memset_io);

void _memcpy_fromio(void *dest, const volatile void __iomem *src,
                    unsigned long n)
{
        void *vsrc = (void __force *) src;

        mb();
        while(n && (!IO_CHECK_ALIGN(vsrc, 4) || !IO_CHECK_ALIGN(dest, 4))) {
                *((u8 *)dest) = *((volatile u8 *)vsrc);
                eieio();
                vsrc++;
                dest++;
                n--;
        }
        while(n >= 4) {
                *((u32 *)dest) = *((volatile u32 *)vsrc);
                eieio();
                vsrc += 4;
                dest += 4;
                n -= 4;
        }
        while(n) {
                *((u8 *)dest) = *((volatile u8 *)vsrc);
                eieio();
                vsrc++;
                dest++;
                n--;
        }
        mb();
}
EXPORT_SYMBOL(_memcpy_fromio);

void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
{
        void *vdest = (void __force *) dest;

        mb();
        while(n && (!IO_CHECK_ALIGN(vdest, 4) || !IO_CHECK_ALIGN(src, 4))) {
                *((volatile u8 *)vdest) = *((u8 *)src);
                src++;
                vdest++;
                n--;
        }
        while(n >= 4) {
                *((volatile u32 *)vdest) = *((volatile u32 *)src);
                src += 4;
                vdest += 4;
                n-=4;
        }
        while(n) {
                *((volatile u8 *)vdest) = *((u8 *)src);
                src++;
                vdest++;
                n--;
        }
        mb();
}
EXPORT_SYMBOL(_memcpy_toio);