linux-zen-server/arch/riscv/include/asm/io.h

144 lines
5.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* {read,write}{b,w,l,q} based on arch/arm64/include/asm/io.h
* which was based on arch/arm/include/io.h
*
* Copyright (C) 1996-2000 Russell King
* Copyright (C) 2012 ARM Ltd.
* Copyright (C) 2014 Regents of the University of California
*/
#ifndef _ASM_RISCV_IO_H
#define _ASM_RISCV_IO_H
#include <linux/types.h>
#include <linux/pgtable.h>
#include <asm/mmiowb.h>
#include <asm/early_ioremap.h>
/*
* MMIO access functions are separated out to break dependency cycles
* when using {read,write}* fns in low-level headers
*/
#include <asm/mmio.h>
/*
* I/O port access constants.
*/
#ifdef CONFIG_MMU
#define IO_SPACE_LIMIT (PCI_IO_SIZE - 1)
#define PCI_IOBASE ((void __iomem *)PCI_IO_START)
#endif /* CONFIG_MMU */
/*
* Emulation routines for the port-mapped IO space used by some PCI drivers.
* These are defined as being "fully synchronous", but also "not guaranteed to
* be fully ordered with respect to other memory and I/O operations". We're
* going to be on the safe side here and just make them:
* - Fully ordered WRT each other, by bracketing them with two fences. The
* outer set contains both I/O so inX is ordered with outX, while the inner just
* needs the type of the access (I for inX and O for outX).
* - Ordered in the same manner as readX/writeX WRT memory by subsuming their
* fences.
* - Ordered WRT timer reads, so udelay and friends don't get elided by the
* implementation.
* Note that there is no way to actually enforce that outX is a non-posted
* operation on RISC-V, but hopefully the timer ordering constraint is
* sufficient to ensure this works sanely on controllers that support I/O
* writes.
*/
#define __io_pbr() __asm__ __volatile__ ("fence io,i" : : : "memory");
#define __io_par(v) __asm__ __volatile__ ("fence i,ior" : : : "memory");
#define __io_pbw() __asm__ __volatile__ ("fence iow,o" : : : "memory");
#define __io_paw() __asm__ __volatile__ ("fence o,io" : : : "memory");
/*
* Accesses from a single hart to a single I/O address must be ordered. This
* allows us to use the raw read macros, but we still need to fence before and
* after the block to ensure ordering WRT other macros. These are defined to
* perform host-endian accesses so we use __raw instead of __cpu.
*/
#define __io_reads_ins(port, ctype, len, bfence, afence) \
static inline void __ ## port ## len(const volatile void __iomem *addr, \
void *buffer, \
unsigned int count) \
{ \
bfence; \
if (count) { \
ctype *buf = buffer; \
\
do { \
ctype x = __raw_read ## len(addr); \
*buf++ = x; \
} while (--count); \
} \
afence; \
}
#define __io_writes_outs(port, ctype, len, bfence, afence) \
static inline void __ ## port ## len(volatile void __iomem *addr, \
const void *buffer, \
unsigned int count) \
{ \
bfence; \
if (count) { \
const ctype *buf = buffer; \
\
do { \
__raw_write ## len(*buf++, addr); \
} while (--count); \
} \
afence; \
}
__io_reads_ins(reads, u8, b, __io_br(), __io_ar(addr))
__io_reads_ins(reads, u16, w, __io_br(), __io_ar(addr))
__io_reads_ins(reads, u32, l, __io_br(), __io_ar(addr))
#define readsb(addr, buffer, count) __readsb(addr, buffer, count)
#define readsw(addr, buffer, count) __readsw(addr, buffer, count)
#define readsl(addr, buffer, count) __readsl(addr, buffer, count)
__io_reads_ins(ins, u8, b, __io_pbr(), __io_par(addr))
__io_reads_ins(ins, u16, w, __io_pbr(), __io_par(addr))
__io_reads_ins(ins, u32, l, __io_pbr(), __io_par(addr))
#define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count)
#define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count)
#define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
__io_writes_outs(writes, u8, b, __io_bw(), __io_aw())
__io_writes_outs(writes, u16, w, __io_bw(), __io_aw())
__io_writes_outs(writes, u32, l, __io_bw(), __io_aw())
#define writesb(addr, buffer, count) __writesb(addr, buffer, count)
#define writesw(addr, buffer, count) __writesw(addr, buffer, count)
#define writesl(addr, buffer, count) __writesl(addr, buffer, count)
__io_writes_outs(outs, u8, b, __io_pbw(), __io_paw())
__io_writes_outs(outs, u16, w, __io_pbw(), __io_paw())
__io_writes_outs(outs, u32, l, __io_pbw(), __io_paw())
#define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count)
#define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count)
#define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
#ifdef CONFIG_64BIT
__io_reads_ins(reads, u64, q, __io_br(), __io_ar(addr))
#define readsq(addr, buffer, count) __readsq(addr, buffer, count)
__io_reads_ins(ins, u64, q, __io_pbr(), __io_par(addr))
#define insq(addr, buffer, count) __insq(PCI_IOBASE + (addr), buffer, count)
__io_writes_outs(writes, u64, q, __io_bw(), __io_aw())
#define writesq(addr, buffer, count) __writesq(addr, buffer, count)
__io_writes_outs(outs, u64, q, __io_pbr(), __io_paw())
#define outsq(addr, buffer, count) __outsq(PCI_IOBASE + (addr), buffer, count)
#endif
#include <asm-generic/io.h>
#ifdef CONFIG_MMU
#define arch_memremap_wb(addr, size) \
((__force void *)ioremap_prot((addr), (size), _PAGE_KERNEL))
#endif
#endif /* _ASM_RISCV_IO_H */