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Diffstat (limited to 'arch/riscv/include/asm/io.h')
| -rw-r--r-- | arch/riscv/include/asm/io.h | 303 |
1 files changed, 303 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h new file mode 100644 index 000000000000..c1f32cfcc79b --- /dev/null +++ b/arch/riscv/include/asm/io.h @@ -0,0 +1,303 @@ +/* + * {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 + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _ASM_RISCV_IO_H +#define _ASM_RISCV_IO_H + +#ifdef CONFIG_MMU + +extern void __iomem *ioremap(phys_addr_t offset, unsigned long size); + +/* + * The RISC-V ISA doesn't yet specify how to query or modify PMAs, so we can't + * change the properties of memory regions. This should be fixed by the + * upcoming platform spec. + */ +#define ioremap_nocache(addr, size) ioremap((addr), (size)) +#define ioremap_wc(addr, size) ioremap((addr), (size)) +#define ioremap_wt(addr, size) ioremap((addr), (size)) + +extern void iounmap(void __iomem *addr); + +#endif /* CONFIG_MMU */ + +/* Generic IO read/write. These perform native-endian accesses. */ +#define __raw_writeb __raw_writeb +static inline void __raw_writeb(u8 val, volatile void __iomem *addr) +{ + asm volatile("sb %0, 0(%1)" : : "r" (val), "r" (addr)); +} + +#define __raw_writew __raw_writew +static inline void __raw_writew(u16 val, volatile void __iomem *addr) +{ + asm volatile("sh %0, 0(%1)" : : "r" (val), "r" (addr)); +} + +#define __raw_writel __raw_writel +static inline void __raw_writel(u32 val, volatile void __iomem *addr) +{ + asm volatile("sw %0, 0(%1)" : : "r" (val), "r" (addr)); +} + +#ifdef CONFIG_64BIT +#define __raw_writeq __raw_writeq +static inline void __raw_writeq(u64 val, volatile void __iomem *addr) +{ + asm volatile("sd %0, 0(%1)" : : "r" (val), "r" (addr)); +} +#endif + +#define __raw_readb __raw_readb +static inline u8 __raw_readb(const volatile void __iomem *addr) +{ + u8 val; + + asm volatile("lb %0, 0(%1)" : "=r" (val) : "r" (addr)); + return val; +} + +#define __raw_readw __raw_readw +static inline u16 __raw_readw(const volatile void __iomem *addr) +{ + u16 val; + + asm volatile("lh %0, 0(%1)" : "=r" (val) : "r" (addr)); + return val; +} + +#define __raw_readl __raw_readl +static inline u32 __raw_readl(const volatile void __iomem *addr) +{ + u32 val; + + asm volatile("lw %0, 0(%1)" : "=r" (val) : "r" (addr)); + return val; +} + +#ifdef CONFIG_64BIT +#define __raw_readq __raw_readq +static inline u64 __raw_readq(const volatile void __iomem *addr) +{ + u64 val; + + asm volatile("ld %0, 0(%1)" : "=r" (val) : "r" (addr)); + return val; +} +#endif + +/* + * FIXME: I'm flip-flopping on whether or not we should keep this or enforce + * the ordering with I/O on spinlocks like PowerPC does. The worry is that + * drivers won't get this correct, but I also don't want to introduce a fence + * into the lock code that otherwise only uses AMOs (and is essentially defined + * by the ISA to be correct). For now I'm leaving this here: "o,w" is + * sufficient to ensure that all writes to the device have completed before the + * write to the spinlock is allowed to commit. I surmised this from reading + * "ACQUIRES VS I/O ACCESSES" in memory-barriers.txt. + */ +#define mmiowb() __asm__ __volatile__ ("fence o,w" : : : "memory"); + +/* + * Unordered I/O memory access primitives. These are even more relaxed than + * the relaxed versions, as they don't even order accesses between successive + * operations to the I/O regions. + */ +#define readb_cpu(c) ({ u8 __r = __raw_readb(c); __r; }) +#define readw_cpu(c) ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; }) +#define readl_cpu(c) ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; }) + +#define writeb_cpu(v,c) ((void)__raw_writeb((v),(c))) +#define writew_cpu(v,c) ((void)__raw_writew((__force u16)cpu_to_le16(v),(c))) +#define writel_cpu(v,c) ((void)__raw_writel((__force u32)cpu_to_le32(v),(c))) + +#ifdef CONFIG_64BIT +#define readq_cpu(c) ({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; }) +#define writeq_cpu(v,c) ((void)__raw_writeq((__force u64)cpu_to_le64(v),(c))) +#endif + +/* + * Relaxed I/O memory access primitives. These follow the Device memory + * ordering rules but do not guarantee any ordering relative to Normal memory + * accesses. These are defined to order the indicated access (either a read or + * write) with all other I/O memory accesses. Since the platform specification + * defines that all I/O regions are strongly ordered on channel 2, no explicit + * fences are required to enforce this ordering. + */ +/* FIXME: These are now the same as asm-generic */ +#define __io_rbr() do {} while (0) +#define __io_rar() do {} while (0) +#define __io_rbw() do {} while (0) +#define __io_raw() do {} while (0) + +#define readb_relaxed(c) ({ u8 __v; __io_rbr(); __v = readb_cpu(c); __io_rar(); __v; }) +#define readw_relaxed(c) ({ u16 __v; __io_rbr(); __v = readw_cpu(c); __io_rar(); __v; }) +#define readl_relaxed(c) ({ u32 __v; __io_rbr(); __v = readl_cpu(c); __io_rar(); __v; }) + +#define writeb_relaxed(v,c) ({ __io_rbw(); writeb_cpu((v),(c)); __io_raw(); }) +#define writew_relaxed(v,c) ({ __io_rbw(); writew_cpu((v),(c)); __io_raw(); }) +#define writel_relaxed(v,c) ({ __io_rbw(); writel_cpu((v),(c)); __io_raw(); }) + +#ifdef CONFIG_64BIT +#define readq_relaxed(c) ({ u64 __v; __io_rbr(); __v = readq_cpu(c); __io_rar(); __v; }) +#define writeq_relaxed(v,c) ({ __io_rbw(); writeq_cpu((v),(c)); __io_raw(); }) +#endif + +/* + * I/O memory access primitives. Reads are ordered relative to any + * following Normal memory access. Writes are ordered relative to any prior + * Normal memory access. The memory barriers here are necessary as RISC-V + * doesn't define any ordering between the memory space and the I/O space. + */ +#define __io_br() do {} while (0) +#define __io_ar() __asm__ __volatile__ ("fence i,r" : : : "memory"); +#define __io_bw() __asm__ __volatile__ ("fence w,o" : : : "memory"); +#define __io_aw() do {} while (0) + +#define readb(c) ({ u8 __v; __io_br(); __v = readb_cpu(c); __io_ar(); __v; }) +#define readw(c) ({ u16 __v; __io_br(); __v = readw_cpu(c); __io_ar(); __v; }) +#define readl(c) ({ u32 __v; __io_br(); __v = readl_cpu(c); __io_ar(); __v; }) + +#define writeb(v,c) ({ __io_bw(); writeb_cpu((v),(c)); __io_aw(); }) +#define writew(v,c) ({ __io_bw(); writew_cpu((v),(c)); __io_aw(); }) +#define writel(v,c) ({ __io_bw(); writel_cpu((v),(c)); __io_aw(); }) + +#ifdef CONFIG_64BIT +#define readq(c) ({ u64 __v; __io_br(); __v = readq_cpu(c); __io_ar(); __v; }) +#define writeq(v,c) ({ __io_bw(); writeq_cpu((v),(c)); __io_aw(); }) +#endif + +/* + * 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() __asm__ __volatile__ ("fence i,ior" : : : "memory"); +#define __io_pbw() __asm__ __volatile__ ("fence iow,o" : : : "memory"); +#define __io_paw() __asm__ __volatile__ ("fence o,io" : : : "memory"); + +#define inb(c) ({ u8 __v; __io_pbr(); __v = readb_cpu((void*)(PCI_IOBASE + (c))); __io_par(); __v; }) +#define inw(c) ({ u16 __v; __io_pbr(); __v = readw_cpu((void*)(PCI_IOBASE + (c))); __io_par(); __v; }) +#define inl(c) ({ u32 __v; __io_pbr(); __v = readl_cpu((void*)(PCI_IOBASE + (c))); __io_par(); __v; }) + +#define outb(v,c) ({ __io_pbw(); writeb_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) +#define outw(v,c) ({ __io_pbw(); writew_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) +#define outl(v,c) ({ __io_pbw(); writel_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) + +#ifdef CONFIG_64BIT +#define inq(c) ({ u64 __v; __io_pbr(); __v = readq_cpu((void*)(c)); __io_par(); __v; }) +#define outq(v,c) ({ __io_pbw(); writeq_cpu((v),(void*)(c)); __io_paw(); }) +#endif + +/* + * 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_writeq(*buf++, addr); \ + } while (--count); \ + } \ + afence; \ + } + +__io_reads_ins(reads, u8, b, __io_br(), __io_ar()) +__io_reads_ins(reads, u16, w, __io_br(), __io_ar()) +__io_reads_ins(reads, u32, l, __io_br(), __io_ar()) +#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()) +__io_reads_ins(ins, u16, w, __io_pbr(), __io_par()) +__io_reads_ins(ins, u32, l, __io_pbr(), __io_par()) +#define insb(addr, buffer, count) __insb((void __iomem *)addr, buffer, count) +#define insw(addr, buffer, count) __insw((void __iomem *)addr, buffer, count) +#define insl(addr, buffer, count) __insl((void __iomem *)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((void __iomem *)addr, buffer, count) +#define outsw(addr, buffer, count) __outsw((void __iomem *)addr, buffer, count) +#define outsl(addr, buffer, count) __outsl((void __iomem *)addr, buffer, count) + +#ifdef CONFIG_64BIT +__io_reads_ins(reads, u64, q, __io_br(), __io_ar()) +#define readsq(addr, buffer, count) __readsq(addr, buffer, count) + +__io_reads_ins(ins, u64, q, __io_pbr(), __io_par()) +#define insq(addr, buffer, count) __insq((void __iomem *)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((void __iomem *)addr, buffer, count) +#endif + +#include <asm-generic/io.h> + +#endif /* _ASM_RISCV_IO_H */ |