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 | |