io-mapping.h revision 1.10
1 /* $NetBSD: io-mapping.h,v 1.10 2021/12/19 12:03:30 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 bus_size_t diom_mapsize; 49 bool diom_atomic; 50 }; 51 52 static inline bool 53 bus_space_io_mapping_init_wc(bus_space_tag_t bst, struct io_mapping *mapping, 54 bus_addr_t addr, bus_size_t size) 55 { 56 bus_size_t offset; 57 58 KASSERT(PAGE_SIZE <= size); 59 KASSERT(0 == (size & (PAGE_SIZE - 1))); 60 KASSERT(__type_fit(off_t, size)); 61 62 /* 63 * XXX For x86: Reserve the region (bus_space_reserve) and set 64 * an MTRR to make it write-combining. Doesn't matter if we 65 * have PAT and we use pmap_kenter_pa, but matters if we don't 66 * have PAT or if we later make this use direct map. 67 */ 68 69 /* Make sure the region is mappable. */ 70 for (offset = 0; offset < size; offset += PAGE_SIZE) { 71 if (bus_space_mmap(bst, addr, offset, PROT_READ|PROT_WRITE, 72 BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE) 73 == (paddr_t)-1) 74 return false; 75 } 76 77 /* Initialize the mapping record. */ 78 mapping->diom_bst = bst; 79 mapping->base = addr; 80 mapping->size = size; 81 mapping->diom_mapsize = 0; 82 mapping->diom_atomic = false; 83 84 /* Allocate kva for one page. */ 85 mapping->diom_va = uvm_km_alloc(kernel_map, PAGE_SIZE, PAGE_SIZE, 86 UVM_KMF_VAONLY | UVM_KMF_WAITVA); 87 KASSERT(mapping->diom_va != 0); 88 89 return true; 90 } 91 92 static inline void 93 io_mapping_fini(struct io_mapping *mapping) 94 { 95 96 KASSERT(mapping->diom_mapsize == 0); 97 KASSERT(!mapping->diom_atomic); 98 99 uvm_km_free(kernel_map, mapping->diom_va, PAGE_SIZE, UVM_KMF_VAONLY); 100 mapping->diom_va = 0; /* paranoia */ 101 } 102 103 static inline struct io_mapping * 104 bus_space_io_mapping_create_wc(bus_space_tag_t bst, bus_addr_t addr, 105 bus_size_t size) 106 { 107 struct io_mapping *mapping; 108 109 mapping = kmem_alloc(sizeof(*mapping), KM_SLEEP); 110 if (!bus_space_io_mapping_init_wc(bst, mapping, addr, size)) { 111 kmem_free(mapping, sizeof(*mapping)); 112 return NULL; 113 } 114 115 return mapping; 116 } 117 118 static inline void 119 io_mapping_free(struct io_mapping *mapping) 120 { 121 122 io_mapping_fini(mapping); 123 kmem_free(mapping, sizeof(*mapping)); 124 } 125 126 static inline void * 127 io_mapping_map_wc(struct io_mapping *mapping, bus_addr_t offset, 128 bus_size_t size) 129 { 130 bus_size_t pg, npgs = size >> PAGE_SHIFT; 131 vaddr_t va; 132 paddr_t cookie; 133 134 KASSERT(0 == (offset & (PAGE_SIZE - 1))); 135 KASSERT(PAGE_SIZE <= mapping->size); 136 KASSERT(offset <= (mapping->size - PAGE_SIZE)); 137 KASSERT(__type_fit(off_t, offset)); 138 KASSERT(mapping->diom_mapsize == 0); 139 KASSERT(!mapping->diom_atomic); 140 141 va = uvm_km_alloc(kernel_map, size, PAGE_SIZE, 142 UVM_KMF_VAONLY|UVM_KMF_WAITVA); 143 for (pg = 0; pg < npgs; pg++) { 144 cookie = bus_space_mmap(mapping->diom_bst, mapping->base, 145 offset + pg*PAGE_SIZE, 146 PROT_READ|PROT_WRITE, 147 BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE); 148 KASSERT(cookie != (paddr_t)-1); 149 150 pmap_kenter_pa(va, pmap_phys_address(cookie), 151 PROT_READ|PROT_WRITE, pmap_mmap_flags(cookie)); 152 } 153 pmap_update(pmap_kernel()); 154 155 mapping->diom_mapsize = size; 156 mapping->diom_atomic = false; 157 return (void *)va; 158 } 159 160 static inline void 161 io_mapping_unmap(struct io_mapping *mapping, void *ptr __diagused) 162 { 163 vaddr_t va = (vaddr_t)ptr; 164 165 KASSERT(mapping->diom_mapsize); 166 KASSERT(!mapping->diom_atomic); 167 KASSERT(mapping->diom_va != va); 168 169 pmap_kremove(va, PAGE_SIZE); 170 pmap_update(pmap_kernel()); 171 172 uvm_km_free(kernel_map, va, mapping->diom_mapsize, UVM_KMF_VAONLY); 173 174 mapping->diom_mapsize = 0; 175 mapping->diom_atomic = false; 176 } 177 178 static inline void * 179 io_mapping_map_atomic_wc(struct io_mapping *mapping, bus_addr_t offset) 180 { 181 paddr_t cookie; 182 183 KASSERT(0 == (offset & (PAGE_SIZE - 1))); 184 KASSERT(PAGE_SIZE <= mapping->size); 185 KASSERT(offset <= (mapping->size - PAGE_SIZE)); 186 KASSERT(__type_fit(off_t, offset)); 187 KASSERT(mapping->diom_mapsize == 0); 188 KASSERT(!mapping->diom_atomic); 189 190 cookie = bus_space_mmap(mapping->diom_bst, mapping->base, offset, 191 PROT_READ|PROT_WRITE, 192 BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE); 193 KASSERT(cookie != (paddr_t)-1); 194 195 pmap_kenter_pa(mapping->diom_va, pmap_phys_address(cookie), 196 PROT_READ|PROT_WRITE, pmap_mmap_flags(cookie)); 197 pmap_update(pmap_kernel()); 198 199 mapping->diom_mapsize = PAGE_SIZE; 200 mapping->diom_atomic = true; 201 return (void *)mapping->diom_va; 202 } 203 204 static inline void 205 io_mapping_unmap_atomic(struct io_mapping *mapping, void *ptr __diagused) 206 { 207 208 KASSERT(mapping->diom_mapsize); 209 KASSERT(mapping->diom_atomic); 210 KASSERT(mapping->diom_va == (vaddr_t)ptr); 211 212 pmap_kremove(mapping->diom_va, PAGE_SIZE); 213 pmap_update(pmap_kernel()); 214 215 mapping->diom_mapsize = 0; 216 mapping->diom_atomic = false; 217 } 218 219 #endif /* _LINUX_IO_MAPPING_H_ */ 220
Indexes created Mon Sep 22 13:09:51 GMT 2025