xref: /kernel/linux/linux-5.10/arch/csky/include/asm/io.h (revision 8c2ecf20)
1/* SPDX-License-Identifier: GPL-2.0 */
2// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3
4#ifndef __ASM_CSKY_IO_H
5#define __ASM_CSKY_IO_H
6
7#include <linux/pgtable.h>
8#include <linux/types.h>
9#include <linux/version.h>
10
11/*
12 * I/O memory access primitives. Reads are ordered relative to any
13 * following Normal memory access. Writes are ordered relative to any prior
14 * Normal memory access.
15 *
16 * For CACHEV1 (807, 810), store instruction could fast retire, so we need
17 * another mb() to prevent st fast retire.
18 *
19 * For CACHEV2 (860), store instruction with PAGE_ATTR_NO_BUFFERABLE won't
20 * fast retire.
21 */
22#define readb(c)		({ u8  __v = readb_relaxed(c); rmb(); __v; })
23#define readw(c)		({ u16 __v = readw_relaxed(c); rmb(); __v; })
24#define readl(c)		({ u32 __v = readl_relaxed(c); rmb(); __v; })
25
26#ifdef CONFIG_CPU_HAS_CACHEV2
27#define writeb(v,c)		({ wmb(); writeb_relaxed((v),(c)); })
28#define writew(v,c)		({ wmb(); writew_relaxed((v),(c)); })
29#define writel(v,c)		({ wmb(); writel_relaxed((v),(c)); })
30#else
31#define writeb(v,c)		({ wmb(); writeb_relaxed((v),(c)); mb(); })
32#define writew(v,c)		({ wmb(); writew_relaxed((v),(c)); mb(); })
33#define writel(v,c)		({ wmb(); writel_relaxed((v),(c)); mb(); })
34#endif
35
36/*
37 * I/O memory mapping functions.
38 */
39#define ioremap_wc(addr, size) \
40	ioremap_prot((addr), (size), \
41		(_PAGE_IOREMAP & ~_CACHE_MASK) | _CACHE_UNCACHED)
42
43#include <asm-generic/io.h>
44
45#endif /* __ASM_CSKY_IO_H */
46