| 1 | /* $NetBSD: bus_dma_hacks.h,v 1.8 2015/10/17 21:11:06 jmcneill 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 _DRM_BUS_DMA_HACKS_H_ |
| 33 | #define _DRM_BUS_DMA_HACKS_H_ |
| 34 | |
| 35 | #include <sys/cdefs.h> |
| 36 | #include <sys/bus.h> |
| 37 | #include <sys/kmem.h> |
| 38 | #include <sys/queue.h> |
| 39 | |
| 40 | #include <uvm/uvm.h> |
| 41 | #include <uvm/uvm_extern.h> |
| 42 | |
| 43 | #if defined(__i386__) || defined(__x86_64__) |
| 44 | #include <x86/bus_private.h> |
| 45 | #include <x86/machdep.h> |
| 46 | #elif defined(__arm__) |
| 47 | #else |
| 48 | #error DRM GEM/TTM need new MI bus_dma APIs! Halp! |
| 49 | #endif |
| 50 | |
| 51 | static inline int |
| 52 | bus_dmamem_wire_uvm_object(bus_dma_tag_t tag, struct uvm_object *uobj, |
| 53 | off_t start, bus_size_t size, struct pglist *pages, bus_size_t alignment, |
| 54 | bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, |
| 55 | int flags) |
| 56 | { |
| 57 | struct pglist pageq; |
| 58 | struct vm_page *page; |
| 59 | unsigned i; |
| 60 | int error; |
| 61 | |
| 62 | /* |
| 63 | * XXX `#ifdef __x86_64__' is a horrible way to work around a |
| 64 | * completely stupid GCC warning that encourages unsafe, |
| 65 | * nonportable code and has no obvious way to be selectively |
| 66 | * suppressed. |
| 67 | */ |
| 68 | #if __x86_64__ |
| 69 | KASSERT(size <= __type_max(off_t)); |
| 70 | #endif |
| 71 | |
| 72 | KASSERT(start <= (__type_max(off_t) - size)); |
| 73 | KASSERT(alignment == PAGE_SIZE); /* XXX */ |
| 74 | KASSERT(0 < nsegs); |
| 75 | |
| 76 | if (pages == NULL) { |
| 77 | TAILQ_INIT(&pageq); |
| 78 | pages = &pageq; |
| 79 | } |
| 80 | |
| 81 | error = uvm_obj_wirepages(uobj, start, (start + size), pages); |
| 82 | if (error) |
| 83 | goto fail0; |
| 84 | |
| 85 | page = TAILQ_FIRST(pages); |
| 86 | KASSERT(page != NULL); |
| 87 | |
| 88 | for (i = 0; i < nsegs; i++) { |
| 89 | if (page == NULL) { |
| 90 | error = EFBIG; |
| 91 | goto fail1; |
| 92 | } |
| 93 | segs[i].ds_addr = VM_PAGE_TO_PHYS(page); |
| 94 | segs[i].ds_len = MIN(PAGE_SIZE, size); |
| 95 | size -= PAGE_SIZE; |
| 96 | page = TAILQ_NEXT(page, pageq.queue); |
| 97 | } |
| 98 | KASSERT(page == NULL); |
| 99 | |
| 100 | /* Success! */ |
| 101 | *rsegs = nsegs; |
| 102 | return 0; |
| 103 | |
| 104 | fail1: uvm_obj_unwirepages(uobj, start, (start + size)); |
| 105 | fail0: return error; |
| 106 | } |
| 107 | |
| 108 | static inline void |
| 109 | bus_dmamem_unwire_uvm_object(bus_dma_tag_t tag __unused, |
| 110 | struct uvm_object *uobj, off_t start, bus_size_t size, |
| 111 | bus_dma_segment_t *segs __unused, int nsegs __unused) |
| 112 | { |
| 113 | uvm_obj_unwirepages(uobj, start, (start + size)); |
| 114 | } |
| 115 | |
| 116 | static inline int |
| 117 | bus_dmamem_pgfl(bus_dma_tag_t tag) |
| 118 | { |
| 119 | #if defined(__i386__) || defined(__x86_64__) |
| 120 | return x86_select_freelist(tag->_bounce_alloc_hi - 1); |
| 121 | #else |
| 122 | return VM_FREELIST_DEFAULT; |
| 123 | #endif |
| 124 | } |
| 125 | |
| 126 | static inline int |
| 127 | bus_dmamap_load_pglist(bus_dma_tag_t tag, bus_dmamap_t map, |
| 128 | struct pglist *pglist, bus_size_t size, int flags) |
| 129 | { |
| 130 | km_flag_t kmflags; |
| 131 | bus_dma_segment_t *segs; |
| 132 | int nsegs, seg; |
| 133 | struct vm_page *page; |
| 134 | int error; |
| 135 | |
| 136 | nsegs = 0; |
| 137 | TAILQ_FOREACH(page, pglist, pageq.queue) { |
| 138 | if (nsegs == MIN(INT_MAX, (SIZE_MAX / sizeof(segs[0])))) |
| 139 | return ENOMEM; |
| 140 | nsegs++; |
| 141 | } |
| 142 | |
| 143 | KASSERT(nsegs <= (SIZE_MAX / sizeof(segs[0]))); |
| 144 | switch (flags & (BUS_DMA_WAITOK|BUS_DMA_NOWAIT)) { |
| 145 | case BUS_DMA_WAITOK: kmflags = KM_SLEEP; break; |
| 146 | case BUS_DMA_NOWAIT: kmflags = KM_NOSLEEP; break; |
| 147 | default: panic("invalid flags: %d" , flags); |
| 148 | } |
| 149 | segs = kmem_alloc((nsegs * sizeof(segs[0])), kmflags); |
| 150 | if (segs == NULL) |
| 151 | return ENOMEM; |
| 152 | |
| 153 | seg = 0; |
| 154 | TAILQ_FOREACH(page, pglist, pageq.queue) { |
| 155 | segs[seg].ds_addr = VM_PAGE_TO_PHYS(page); |
| 156 | segs[seg].ds_len = PAGE_SIZE; |
| 157 | seg++; |
| 158 | } |
| 159 | |
| 160 | error = bus_dmamap_load_raw(tag, map, segs, nsegs, size, flags); |
| 161 | if (error) |
| 162 | goto fail0; |
| 163 | |
| 164 | /* Success! */ |
| 165 | error = 0; |
| 166 | goto out; |
| 167 | |
| 168 | fail1: __unused |
| 169 | bus_dmamap_unload(tag, map); |
| 170 | fail0: KASSERT(error); |
| 171 | out: kmem_free(segs, (nsegs * sizeof(segs[0]))); |
| 172 | return error; |
| 173 | } |
| 174 | |
| 175 | #endif /* _DRM_BUS_DMA_HACKS_H_ */ |
| 176 | |