| 1 | /* $NetBSD: io-mapping.h,v 1.5 2015/02/25 14:02:43 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 diom_addr; |
| 46 | bus_size_t diom_size; |
| 47 | vaddr_t diom_va; |
| 48 | bool diom_mapped; |
| 49 | }; |
| 50 | |
| 51 | static inline struct io_mapping * |
| 52 | bus_space_io_mapping_create_wc(bus_space_tag_t bst, bus_addr_t addr, |
| 53 | bus_size_t size) |
| 54 | { |
| 55 | struct io_mapping *mapping; |
| 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 NULL; |
| 75 | } |
| 76 | |
| 77 | /* Create a mapping record. */ |
| 78 | mapping = kmem_alloc(sizeof(*mapping), KM_SLEEP); |
| 79 | mapping->diom_bst = bst; |
| 80 | mapping->diom_addr = addr; |
| 81 | mapping->diom_size = size; |
| 82 | mapping->diom_mapped = 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 mapping; |
| 90 | } |
| 91 | |
| 92 | static inline void |
| 93 | io_mapping_free(struct io_mapping *mapping) |
| 94 | { |
| 95 | |
| 96 | KASSERT(!mapping->diom_mapped); |
| 97 | |
| 98 | uvm_km_free(kernel_map, mapping->diom_va, PAGE_SIZE, UVM_KMF_VAONLY); |
| 99 | kmem_free(mapping, sizeof(*mapping)); |
| 100 | } |
| 101 | |
| 102 | static inline void * |
| 103 | io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) |
| 104 | { |
| 105 | paddr_t cookie; |
| 106 | |
| 107 | KASSERT(0 == (offset & (PAGE_SIZE - 1))); |
| 108 | KASSERT(PAGE_SIZE <= mapping->diom_size); |
| 109 | KASSERT(offset <= (mapping->diom_size - PAGE_SIZE)); |
| 110 | KASSERT(__type_fit(off_t, offset)); |
| 111 | KASSERT(!mapping->diom_mapped); |
| 112 | |
| 113 | cookie = bus_space_mmap(mapping->diom_bst, mapping->diom_addr, offset, |
| 114 | PROT_READ|PROT_WRITE, |
| 115 | BUS_SPACE_MAP_LINEAR|BUS_SPACE_MAP_PREFETCHABLE); |
| 116 | KASSERT(cookie != (paddr_t)-1); |
| 117 | |
| 118 | pmap_kenter_pa(mapping->diom_va, pmap_phys_address(cookie), |
| 119 | PROT_READ|PROT_WRITE, pmap_mmap_flags(cookie)); |
| 120 | pmap_update(pmap_kernel()); |
| 121 | |
| 122 | mapping->diom_mapped = true; |
| 123 | return (void *)mapping->diom_va; |
| 124 | } |
| 125 | |
| 126 | static inline void |
| 127 | io_mapping_unmap(struct io_mapping *mapping, void *ptr __diagused) |
| 128 | { |
| 129 | |
| 130 | KASSERT(mapping->diom_mapped); |
| 131 | KASSERT(mapping->diom_va == (vaddr_t)ptr); |
| 132 | |
| 133 | pmap_kremove(mapping->diom_va, PAGE_SIZE); |
| 134 | pmap_update(pmap_kernel()); |
| 135 | |
| 136 | mapping->diom_mapped = false; |
| 137 | } |
| 138 | |
| 139 | static inline void * |
| 140 | io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) |
| 141 | { |
| 142 | |
| 143 | return io_mapping_map_wc(mapping, offset); |
| 144 | } |
| 145 | |
| 146 | static inline void |
| 147 | io_mapping_unmap_atomic(struct io_mapping *mapping, void *ptr) |
| 148 | { |
| 149 | |
| 150 | io_mapping_unmap(mapping, ptr); |
| 151 | } |
| 152 | |
| 153 | #endif /* _LINUX_IO_MAPPING_H_ */ |
| 154 | |