io-mapping.h revision 1.9
1 /* $NetBSD: io-mapping.h,v 1.9 2021/12/19 11:57:43 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUX_IO_MAPPING_H_ 33 #define _LINUX_IO_MAPPING_H_ 34 35 #include <sys/param.h> 36 #include <sys/bus.h> 37 #include <sys/kmem.h> 38 #include <sys/systm.h> 39 #include <sys/mman.h> 40 41 #include <uvm/uvm_extern.h> 42 43 struct io_mapping { 44 bus_space_tag_t diom_bst; 45 bus_addr_t base; /* Linux API */ 46 bus_size_t size; /* Linux API */ 47 vaddr_t diom_va; 48 bool diom_mapped; 49 }; 50 51 static inline bool 52 bus_space_io_mapping_init_wc(bus_space_tag_t bst, struct io_mapping *mapping, 53 bus_addr_t addr, bus_size_t size) 54 { 55 bus_size_t offset; 56 57 KASSERT(PAGE_SIZE <= size); 58 KASSERT(0 == (size & (PAGE_SIZE - 1))); 59 KASSERT(__type_fit(off_t, size)); 60 61 /* 62 * XXX For x86: Reserve the region (bus_space_reserve) and set 63 * an MTRR to make it write-combining. Doesn't matter if we 64 * have PAT and we use pmap_kenter_pa, but matters if we don't 65 * have PAT or if we later make this use direct map. 66 */ 67 68 /* Make sure the region is mappable. */ 69 for (offset = 0; offset < size; offset += PAGE_SIZE) { 70 if (bus_space_mmap(bst, addr, offset, PROT_READ|PROT_WRITE, 71 BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE) 72 == (paddr_t)-1) 73 return false; 74 } 75 76 /* Initialize the mapping record. */ 77 mapping->diom_bst = bst; 78 mapping->base = addr; 79 mapping->size = size; 80 mapping->diom_mapped = false; 81 82 /* Allocate kva for one page. */ 83 mapping->diom_va = uvm_km_alloc(kernel_map, PAGE_SIZE, PAGE_SIZE, 84 UVM_KMF_VAONLY | UVM_KMF_WAITVA); 85 KASSERT(mapping->diom_va != 0); 86 87 return true; 88 } 89 90 static inline void 91 io_mapping_fini(struct io_mapping *mapping) 92 { 93 94 KASSERT(!mapping->diom_mapped); 95 96 uvm_km_free(kernel_map, mapping->diom_va, PAGE_SIZE, UVM_KMF_VAONLY); 97 mapping->diom_va = 0; /* paranoia */ 98 } 99 100 static inline struct io_mapping * 101 bus_space_io_mapping_create_wc(bus_space_tag_t bst, bus_addr_t addr, 102 bus_size_t size) 103 { 104 struct io_mapping *mapping; 105 106 mapping = kmem_alloc(sizeof(*mapping), KM_SLEEP); 107 if (!bus_space_io_mapping_init_wc(bst, mapping, addr, size)) { 108 kmem_free(mapping, sizeof(*mapping)); 109 return NULL; 110 } 111 112 return mapping; 113 } 114 115 static inline void 116 io_mapping_free(struct io_mapping *mapping) 117 { 118 119 io_mapping_fini(mapping); 120 kmem_free(mapping, sizeof(*mapping)); 121 } 122 123 static inline void * 124 io_mapping_map_wc(struct io_mapping *mapping, bus_addr_t offset, 125 bus_size_t size) 126 { 127 paddr_t cookie; 128 129 KASSERT(size == PAGE_SIZE); 130 KASSERT(0 == (offset & (PAGE_SIZE - 1))); 131 KASSERT(PAGE_SIZE <= mapping->size); 132 KASSERT(offset <= (mapping->size - PAGE_SIZE)); 133 KASSERT(__type_fit(off_t, offset)); 134 KASSERT(!mapping->diom_mapped); 135 136 cookie = bus_space_mmap(mapping->diom_bst, mapping->base, offset, 137 PROT_READ|PROT_WRITE, 138 BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE); 139 KASSERT(cookie != (paddr_t)-1); 140 141 pmap_kenter_pa(mapping->diom_va, pmap_phys_address(cookie), 142 PROT_READ|PROT_WRITE, pmap_mmap_flags(cookie)); 143 pmap_update(pmap_kernel()); 144 145 mapping->diom_mapped = true; 146 return (void *)mapping->diom_va; 147 } 148 149 static inline void 150 io_mapping_unmap(struct io_mapping *mapping, void *ptr __diagused) 151 { 152 153 KASSERT(mapping->diom_mapped); 154 KASSERT(mapping->diom_va == (vaddr_t)ptr); 155 156 pmap_kremove(mapping->diom_va, PAGE_SIZE); 157 pmap_update(pmap_kernel()); 158 159 mapping->diom_mapped = false; 160 } 161 162 static inline void * 163 io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) 164 { 165 166 return io_mapping_map_wc(mapping, offset, PAGE_SIZE); 167 } 168 169 static inline void 170 io_mapping_unmap_atomic(struct io_mapping *mapping, void *ptr) 171 { 172 173 io_mapping_unmap(mapping, ptr); 174 } 175 176 #endif /* _LINUX_IO_MAPPING_H_ */ 177
Indexes created Mon Sep 22 13:09:51 GMT 2025