bus_dmamem_common.c revision 1.5
1/* $NetBSD: bus_dmamem_common.c,v 1.5 2022/11/12 07:48:34 skrll Exp $ */ 2 3/*- 4 * Copyright (c) 1997, 1998, 2009 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 34 35__KERNEL_RCSID(0, "$NetBSD: bus_dmamem_common.c,v 1.5 2022/11/12 07:48:34 skrll Exp $"); 36 37#include <sys/param.h> 38#include <sys/systm.h> 39#include <sys/proc.h> 40#include <sys/bus.h> 41 42#include <uvm/uvm_extern.h> 43#include <uvm/uvm_page.h> 44 45#include <dev/bus_dma/bus_dmamem_common.h> 46 47/* 48 * _bus_dmamem_alloc_range_common -- 49 * Allocate physical memory from the specified physical address range. 50 */ 51int 52_bus_dmamem_alloc_range_common(bus_dma_tag_t t, 53 bus_size_t size, 54 bus_size_t alignment, 55 bus_size_t boundary, 56 bus_dma_segment_t *segs, 57 int nsegs, 58 int *rsegs, 59 int flags, 60 paddr_t low, 61 paddr_t high) 62{ 63 paddr_t curaddr, lastaddr; 64 struct vm_page *m; 65 struct pglist mlist; 66 int curseg, error; 67 68 /* Always round the size. */ 69 size = round_page(size); 70 71 /* Allocate pages from the VM system. */ 72 error = uvm_pglistalloc(size, low, high, alignment, boundary, 73 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 74 if (__predict_false(error != 0)) 75 return (error); 76 77 /* 78 * Compute the location, size, and number of segments actually 79 * returned by the VM system. 80 */ 81 m = TAILQ_FIRST(&mlist); 82 curseg = 0; 83 lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m); 84 segs[curseg].ds_len = PAGE_SIZE; 85 m = TAILQ_NEXT(m, pageq.queue); 86 87 for (; m != NULL; m = TAILQ_NEXT(m, pageq.queue)) { 88 curaddr = VM_PAGE_TO_PHYS(m); 89 KASSERT(curaddr >= low); 90 KASSERT(curaddr < high); 91 if (curaddr == (lastaddr + PAGE_SIZE)) 92 segs[curseg].ds_len += PAGE_SIZE; 93 else { 94 curseg++; 95 segs[curseg].ds_addr = curaddr; 96 segs[curseg].ds_len = PAGE_SIZE; 97 } 98 lastaddr = curaddr; 99 } 100 101 *rsegs = curseg + 1; 102 103 return (0); 104} 105 106/* 107 * _bus_dmamem_free_common -- 108 * Free memory allocated with _bus_dmamem_alloc_range_common() 109 * back to the VM system. 110 */ 111void 112_bus_dmamem_free_common(bus_dma_tag_t t, 113 bus_dma_segment_t *segs, 114 int nsegs) 115{ 116 struct vm_page *m; 117 bus_addr_t addr; 118 struct pglist mlist; 119 int curseg; 120 121 TAILQ_INIT(&mlist); 122 for (curseg = 0; curseg < nsegs; curseg++) { 123 for (addr = segs[curseg].ds_addr; 124 addr < (segs[curseg].ds_addr + segs[curseg].ds_len); 125 addr += PAGE_SIZE) { 126 m = PHYS_TO_VM_PAGE(addr); 127 TAILQ_INSERT_TAIL(&mlist, m, pageq.queue); 128 } 129 } 130 131 uvm_pglistfree(&mlist); 132} 133 134/* 135 * _bus_dmamem_map_common -- 136 * Map memory allocated with _bus_dmamem_alloc_range_common() into 137 * the kernel virtual address space. 138 */ 139int 140_bus_dmamem_map_common(bus_dma_tag_t t, 141 bus_dma_segment_t *segs, 142 int nsegs, 143 size_t size, 144 void **kvap, 145 int flags, 146 int pmapflags) 147{ 148 vaddr_t va; 149 bus_addr_t addr; 150 int curseg; 151 const uvm_flag_t kmflags = 152 (flags & BUS_DMA_NOWAIT) != 0 ? UVM_KMF_NOWAIT : 0; 153 154 size = round_page(size); 155 156 va = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_VAONLY | kmflags); 157 if (__predict_false(va == 0)) 158 return (ENOMEM); 159 160 *kvap = (void *)va; 161 162 for (curseg = 0; curseg < nsegs; curseg++) { 163 for (addr = segs[curseg].ds_addr; 164 addr < (segs[curseg].ds_addr + segs[curseg].ds_len); 165 addr += PAGE_SIZE, va += PAGE_SIZE, size -= PAGE_SIZE) { 166 KASSERT(size != 0); 167 /* XXX pmap_kenter_pa()? */ 168 pmap_enter(pmap_kernel(), va, addr, 169 VM_PROT_READ | VM_PROT_WRITE, 170 pmapflags | PMAP_WIRED | 171 VM_PROT_READ | VM_PROT_WRITE); 172 } 173 } 174 pmap_update(pmap_kernel()); 175 176 return (0); 177} 178 179/* 180 * _bus_dmamem_unmap_common -- 181 * Remove a mapping created with _bus_dmamem_map_common(). 182 */ 183void 184_bus_dmamem_unmap_common(bus_dma_tag_t t, 185 void *kva, 186 size_t size) 187{ 188 189 KASSERT(((vaddr_t)kva & PAGE_MASK) == 0); 190 191 size = round_page(size); 192 /* XXX pmap_kremove()? See above... */ 193 pmap_remove(pmap_kernel(), (vaddr_t)kva, (vaddr_t)kva + size); 194 pmap_update(pmap_kernel()); 195 uvm_km_free(kernel_map, (vaddr_t)kva, size, UVM_KMF_VAONLY); 196} 197 198/* 199 * _bus_dmamem_mmap_common -- 200 * Mmap support for memory allocated with _bus_dmamem_alloc_range_common(). 201 */ 202bus_addr_t 203_bus_dmamem_mmap_common(bus_dma_tag_t t, 204 bus_dma_segment_t *segs, 205 int nsegs, 206 off_t off, 207 int prot, 208 int flags) 209{ 210 int i; 211 212 for (i = 0; i < nsegs; i++) { 213 KASSERT((off & PAGE_MASK) == 0); 214 KASSERT((segs[i].ds_addr & PAGE_MASK) == 0); 215 KASSERT((segs[i].ds_len & PAGE_MASK) == 0); 216 if (off >= segs[i].ds_len) { 217 off -= segs[i].ds_len; 218 continue; 219 } 220 221 /* XXX BUS_DMA_COHERENT */ 222 223 return (segs[i].ds_addr + off); 224 } 225 226 /* Page not found. */ 227 return ((bus_addr_t)-1); 228} 229