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_IO_H 12 #define _ASM_RISCV_IO_H 13 14 #include <linux/types.h> 15 #include <linux/pgtable.h> 16 #include <asm/mmiowb.h> 17 #include <asm/early_ioremap.h> 18 19 /* 20 * MMIO access functions are separated out to break dependency cycles 21 * when using {read,write}* fns in low-level headers 22 */ 23 #include <asm/mmio.h> 24 25 /* 26 * I/O port access constants. 27 */ 28 #ifdef CONFIG_MMU 29 #define IO_SPACE_LIMIT (PCI_IO_SIZE - 1) 30 #define PCI_IOBASE ((void __iomem *)PCI_IO_START) 31 #endif /* CONFIG_MMU */ 32 33 /* 34 * Emulation routines for the port-mapped IO space used by some PCI drivers. 35 * These are defined as being "fully synchronous", but also "not guaranteed to 36 * be fully ordered with respect to other memory and I/O operations". We're 37 * going to be on the safe side here and just make them: 38 * - Fully ordered WRT each other, by bracketing them with two fences. The 39 * outer set contains both I/O so inX is ordered with outX, while the inner just 40 * needs the type of the access (I for inX and O for outX). 41 * - Ordered in the same manner as readX/writeX WRT memory by subsuming their 42 * fences. 43 * - Ordered WRT timer reads, so udelay and friends don't get elided by the 44 * implementation. 45 * Note that there is no way to actually enforce that outX is a non-posted 46 * operation on RISC-V, but hopefully the timer ordering constraint is 47 * sufficient to ensure this works sanely on controllers that support I/O 48 * writes. 49 */ 50 #define __io_pbr() __asm__ __volatile__ ("fence io,i" : : : "memory"); 51 #define __io_par(v) __asm__ __volatile__ ("fence i,ior" : : : "memory"); 52 #define __io_pbw() __asm__ __volatile__ ("fence iow,o" : : : "memory"); 53 #define __io_paw() __asm__ __volatile__ ("fence o,io" : : : "memory"); 54 55 /* 56 * Accesses from a single hart to a single I/O address must be ordered. This 57 * allows us to use the raw read macros, but we still need to fence before and 58 * after the block to ensure ordering WRT other macros. These are defined to 59 * perform host-endian accesses so we use __raw instead of __cpu. 60 */ 61 #define __io_reads_ins(port, ctype, len, bfence, afence) \ 62 static inline void __ ## port ## len(const volatile void __iomem *addr, \ 63 void *buffer, \ 64 unsigned int count) \ 65 { \ 66 bfence; \ 67 if (count) { \ 68 ctype *buf = buffer; \ 69 \ 70 do { \ 71 ctype x = __raw_read ## len(addr); \ 72 *buf++ = x; \ 73 } while (--count); \ 74 } \ 75 afence; \ 76 } 77 78 #define __io_writes_outs(port, ctype, len, bfence, afence) \ 79 static inline void __ ## port ## len(volatile void __iomem *addr, \ 80 const void *buffer, \ 81 unsigned int count) \ 82 { \ 83 bfence; \ 84 if (count) { \ 85 const ctype *buf = buffer; \ 86 \ 87 do { \ 88 __raw_write ## len(*buf++, addr); \ 89 } while (--count); \ 90 } \ 91 afence; \ 92 } 93 94 __io_reads_ins(reads, u8, b, __io_br(), __io_ar(addr)) 95 __io_reads_ins(reads, u16, w, __io_br(), __io_ar(addr)) 96 __io_reads_ins(reads, u32, l, __io_br(), __io_ar(addr)) 97 #define readsb(addr, buffer, count) __readsb(addr, buffer, count) 98 #define readsw(addr, buffer, count) __readsw(addr, buffer, count) 99 #define readsl(addr, buffer, count) __readsl(addr, buffer, count) 100 101 __io_reads_ins(ins, u8, b, __io_pbr(), __io_par(addr)) 102 __io_reads_ins(ins, u16, w, __io_pbr(), __io_par(addr)) 103 __io_reads_ins(ins, u32, l, __io_pbr(), __io_par(addr)) 104 #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count) 105 #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count) 106 #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count) 107 108 __io_writes_outs(writes, u8, b, __io_bw(), __io_aw()) 109 __io_writes_outs(writes, u16, w, __io_bw(), __io_aw()) 110 __io_writes_outs(writes, u32, l, __io_bw(), __io_aw()) 111 #define writesb(addr, buffer, count) __writesb(addr, buffer, count) 112 #define writesw(addr, buffer, count) __writesw(addr, buffer, count) 113 #define writesl(addr, buffer, count) __writesl(addr, buffer, count) 114 115 __io_writes_outs(outs, u8, b, __io_pbw(), __io_paw()) 116 __io_writes_outs(outs, u16, w, __io_pbw(), __io_paw()) 117 __io_writes_outs(outs, u32, l, __io_pbw(), __io_paw()) 118 #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count) 119 #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count) 120 #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count) 121 122 #ifdef CONFIG_64BIT 123 __io_reads_ins(reads, u64, q, __io_br(), __io_ar(addr)) 124 #define readsq(addr, buffer, count) __readsq(addr, buffer, count) 125 126 __io_reads_ins(ins, u64, q, __io_pbr(), __io_par(addr)) 127 #define insq(addr, buffer, count) __insq(PCI_IOBASE + (addr), buffer, count) 128 129 __io_writes_outs(writes, u64, q, __io_bw(), __io_aw()) 130 #define writesq(addr, buffer, count) __writesq(addr, buffer, count) 131 132 __io_writes_outs(outs, u64, q, __io_pbr(), __io_paw()) 133 #define outsq(addr, buffer, count) __outsq(PCI_IOBASE + (addr), buffer, count) 134 #endif 135 136 #include <asm-generic/io.h> 137 138 #ifdef CONFIG_MMU 139 #define arch_memremap_wb(addr, size) \ 140 ((__force void *)ioremap_prot((addr), (size), _PAGE_KERNEL)) 141 #endif 142 143 #endif /* _ASM_RISCV_IO_H */ 144