1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * {read,write}{b,w,l,q} based on arch/arm64/include/asm/io.h 4 * which was based on arch/arm/include/io.h 5 * 6 * Copyright (C) 1996-2000 Russell King 7 * Copyright (C) 2012 ARM Ltd. 8 * Copyright (C) 2014 Regents of the University of California 9 */ 10 11 #ifndef _ASM_RISCV_MMIO_H 12 #define _ASM_RISCV_MMIO_H 13 14 #include <linux/types.h> 15 #include <asm/mmiowb.h> 16 17 /* Generic IO read/write. These perform native-endian accesses. */ 18 #define __raw_writeb __raw_writeb 19 static inline void __raw_writeb(u8 val, volatile void __iomem *addr) 20 { 21 asm volatile("sb %0, 0(%1)" : : "r" (val), "r" (addr)); 22 } 23 24 #define __raw_writew __raw_writew 25 static inline void __raw_writew(u16 val, volatile void __iomem *addr) 26 { 27 asm volatile("sh %0, 0(%1)" : : "r" (val), "r" (addr)); 28 } 29 30 #define __raw_writel __raw_writel 31 static inline void __raw_writel(u32 val, volatile void __iomem *addr) 32 { 33 asm volatile("sw %0, 0(%1)" : : "r" (val), "r" (addr)); 34 } 35 36 #ifdef CONFIG_64BIT 37 #define __raw_writeq __raw_writeq 38 static inline void __raw_writeq(u64 val, volatile void __iomem *addr) 39 { 40 asm volatile("sd %0, 0(%1)" : : "r" (val), "r" (addr)); 41 } 42 #endif 43 44 #define __raw_readb __raw_readb 45 static inline u8 __raw_readb(const volatile void __iomem *addr) 46 { 47 u8 val; 48 49 asm volatile("lb %0, 0(%1)" : "=r" (val) : "r" (addr)); 50 return val; 51 } 52 53 #define __raw_readw __raw_readw 54 static inline u16 __raw_readw(const volatile void __iomem *addr) 55 { 56 u16 val; 57 58 asm volatile("lh %0, 0(%1)" : "=r" (val) : "r" (addr)); 59 return val; 60 } 61 62 #define __raw_readl __raw_readl 63 static inline u32 __raw_readl(const volatile void __iomem *addr) 64 { 65 u32 val; 66 67 asm volatile("lw %0, 0(%1)" : "=r" (val) : "r" (addr)); 68 return val; 69 } 70 71 #ifdef CONFIG_64BIT 72 #define __raw_readq __raw_readq 73 static inline u64 __raw_readq(const volatile void __iomem *addr) 74 { 75 u64 val; 76 77 asm volatile("ld %0, 0(%1)" : "=r" (val) : "r" (addr)); 78 return val; 79 } 80 #endif 81 82 /* 83 * Unordered I/O memory access primitives. These are even more relaxed than 84 * the relaxed versions, as they don't even order accesses between successive 85 * operations to the I/O regions. 86 */ 87 #define readb_cpu(c) ({ u8 __r = __raw_readb(c); __r; }) 88 #define readw_cpu(c) ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; }) 89 #define readl_cpu(c) ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; }) 90 91 #define writeb_cpu(v, c) ((void)__raw_writeb((v), (c))) 92 #define writew_cpu(v, c) ((void)__raw_writew((__force u16)cpu_to_le16(v), (c))) 93 #define writel_cpu(v, c) ((void)__raw_writel((__force u32)cpu_to_le32(v), (c))) 94 95 #ifdef CONFIG_64BIT 96 #define readq_cpu(c) ({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; }) 97 #define writeq_cpu(v, c) ((void)__raw_writeq((__force u64)cpu_to_le64(v), (c))) 98 #endif 99 100 /* 101 * Relaxed I/O memory access primitives. These follow the Device memory 102 * ordering rules but do not guarantee any ordering relative to Normal memory 103 * accesses. These are defined to order the indicated access (either a read or 104 * write) with all other I/O memory accesses to the same peripheral. Since the 105 * platform specification defines that all I/O regions are strongly ordered on 106 * channel 0, no explicit fences are required to enforce this ordering. 107 */ 108 /* FIXME: These are now the same as asm-generic */ 109 #define __io_rbr() do {} while (0) 110 #define __io_rar() do {} while (0) 111 #define __io_rbw() do {} while (0) 112 #define __io_raw() do {} while (0) 113 114 #define readb_relaxed(c) ({ u8 __v; __io_rbr(); __v = readb_cpu(c); __io_rar(); __v; }) 115 #define readw_relaxed(c) ({ u16 __v; __io_rbr(); __v = readw_cpu(c); __io_rar(); __v; }) 116 #define readl_relaxed(c) ({ u32 __v; __io_rbr(); __v = readl_cpu(c); __io_rar(); __v; }) 117 118 #define writeb_relaxed(v, c) ({ __io_rbw(); writeb_cpu((v), (c)); __io_raw(); }) 119 #define writew_relaxed(v, c) ({ __io_rbw(); writew_cpu((v), (c)); __io_raw(); }) 120 #define writel_relaxed(v, c) ({ __io_rbw(); writel_cpu((v), (c)); __io_raw(); }) 121 122 #ifdef CONFIG_64BIT 123 #define readq_relaxed(c) ({ u64 __v; __io_rbr(); __v = readq_cpu(c); __io_rar(); __v; }) 124 #define writeq_relaxed(v, c) ({ __io_rbw(); writeq_cpu((v), (c)); __io_raw(); }) 125 #endif 126 127 /* 128 * I/O memory access primitives. Reads are ordered relative to any following 129 * Normal memory read and delay() loop. Writes are ordered relative to any 130 * prior Normal memory write. The memory barriers here are necessary as RISC-V 131 * doesn't define any ordering between the memory space and the I/O space. 132 */ 133 #define __io_br() do {} while (0) 134 #define __io_ar(v) ({ __asm__ __volatile__ ("fence i,ir" : : : "memory"); }) 135 #define __io_bw() ({ __asm__ __volatile__ ("fence w,o" : : : "memory"); }) 136 #define __io_aw() mmiowb_set_pending() 137 138 #define readb(c) ({ u8 __v; __io_br(); __v = readb_cpu(c); __io_ar(__v); __v; }) 139 #define readw(c) ({ u16 __v; __io_br(); __v = readw_cpu(c); __io_ar(__v); __v; }) 140 #define readl(c) ({ u32 __v; __io_br(); __v = readl_cpu(c); __io_ar(__v); __v; }) 141 142 #define writeb(v, c) ({ __io_bw(); writeb_cpu((v), (c)); __io_aw(); }) 143 #define writew(v, c) ({ __io_bw(); writew_cpu((v), (c)); __io_aw(); }) 144 #define writel(v, c) ({ __io_bw(); writel_cpu((v), (c)); __io_aw(); }) 145 146 #ifdef CONFIG_64BIT 147 #define readq(c) ({ u64 __v; __io_br(); __v = readq_cpu(c); __io_ar(__v); __v; }) 148 #define writeq(v, c) ({ __io_bw(); writeq_cpu((v), (c)); __io_aw(); }) 149 #endif 150 151 #endif /* _ASM_RISCV_MMIO_H */ 152