devmap.c revision 266086
1/*- 2 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: stable/10/sys/arm/arm/devmap.c 266086 2014-05-14 20:17:31Z ian $"); 29 30/* 31 * Routines for mapping device memory. 32 */ 33 34#include "opt_ddb.h" 35 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <vm/vm.h> 39#include <vm/vm_extern.h> 40#include <vm/pmap.h> 41#include <machine/armreg.h> 42#include <machine/devmap.h> 43 44static const struct arm_devmap_entry *devmap_table; 45static boolean_t devmap_bootstrap_done = false; 46 47/* 48 * The allocated-kva (akva) devmap table and metadata. Platforms can call 49 * arm_devmap_add_entry() to add static device mappings to this table using 50 * automatically allocated virtual addresses carved out of the top of kva space. 51 * Allocation begins immediately below the ARM_VECTORS_HIGH address. 52 */ 53#define AKVA_DEVMAP_MAX_ENTRIES 32 54static struct arm_devmap_entry akva_devmap_entries[AKVA_DEVMAP_MAX_ENTRIES]; 55static u_int akva_devmap_idx; 56static vm_offset_t akva_devmap_vaddr = ARM_VECTORS_HIGH; 57 58/* 59 * Print the contents of the static mapping table using the provided printf-like 60 * output function (which will be either printf or db_printf). 61 */ 62static void 63devmap_dump_table(int (*prfunc)(const char *, ...)) 64{ 65 const struct arm_devmap_entry *pd; 66 67 if (devmap_table == NULL || devmap_table[0].pd_size == 0) { 68 prfunc("No static device mappings.\n"); 69 return; 70 } 71 72 prfunc("Static device mappings:\n"); 73 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 74 prfunc(" 0x%08x - 0x%08x mapped at VA 0x%08x\n", 75 pd->pd_pa, pd->pd_pa + pd->pd_size - 1, pd->pd_va); 76 } 77} 78 79/* 80 * Print the contents of the static mapping table. Used for bootverbose. 81 */ 82void 83arm_devmap_print_table() 84{ 85 devmap_dump_table(printf); 86} 87 88/* 89 * Return the "last" kva address used by the registered devmap table. It's 90 * actually the lowest address used by the static mappings, i.e., the address of 91 * the first unusable byte of KVA. 92 */ 93vm_offset_t 94arm_devmap_lastaddr() 95{ 96 const struct arm_devmap_entry *pd; 97 vm_offset_t lowaddr; 98 99 if (akva_devmap_idx > 0) 100 return (akva_devmap_vaddr); 101 102 lowaddr = ARM_VECTORS_HIGH; 103 for (pd = devmap_table; pd != NULL && pd->pd_size != 0; ++pd) { 104 if (lowaddr > pd->pd_va) 105 lowaddr = pd->pd_va; 106 } 107 108 return (lowaddr); 109} 110 111/* 112 * Add an entry to the internal "akva" static devmap table using the given 113 * physical address and size and a virtual address allocated from the top of 114 * kva. This automatically registers the akva table on the first call, so all a 115 * platform has to do is call this routine to install as many mappings as it 116 * needs and when initarm() calls arm_devmap_bootstrap() it will pick up all the 117 * entries in the akva table automatically. 118 */ 119void 120arm_devmap_add_entry(vm_paddr_t pa, vm_size_t sz) 121{ 122 struct arm_devmap_entry *m; 123 124 if (devmap_bootstrap_done) 125 panic("arm_devmap_add_entry() after arm_devmap_bootstrap()"); 126 127 if (akva_devmap_idx == (AKVA_DEVMAP_MAX_ENTRIES - 1)) 128 panic("AKVA_DEVMAP_MAX_ENTRIES is too small"); 129 130 if (akva_devmap_idx == 0) 131 arm_devmap_register_table(akva_devmap_entries); 132 133 /* 134 * Allocate virtual address space from the top of kva downwards. If the 135 * range being mapped is aligned and sized to 1MB boundaries then also 136 * align the virtual address to the next-lower 1MB boundary so that we 137 * end up with a nice efficient section mapping. 138 */ 139 if ((pa & 0x000fffff) == 0 && (sz & 0x000fffff) == 0) { 140 akva_devmap_vaddr = trunc_1mpage(akva_devmap_vaddr - sz); 141 } else { 142 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - sz); 143 } 144 m = &akva_devmap_entries[akva_devmap_idx++]; 145 m->pd_va = akva_devmap_vaddr; 146 m->pd_pa = pa; 147 m->pd_size = sz; 148 m->pd_prot = VM_PROT_READ | VM_PROT_WRITE; 149 m->pd_cache = PTE_DEVICE; 150} 151 152/* 153 * Register the given table as the one to use in arm_devmap_bootstrap(). 154 */ 155void 156arm_devmap_register_table(const struct arm_devmap_entry *table) 157{ 158 159 devmap_table = table; 160} 161 162/* 163 * Map all of the static regions in the devmap table, and remember the devmap 164 * table so the mapdev, ptov, and vtop functions can do lookups later. 165 * 166 * If a non-NULL table pointer is given it is used unconditionally, otherwise 167 * the previously-registered table is used. This smooths transition from legacy 168 * code that fills in a local table then calls this function passing that table, 169 * and newer code that uses arm_devmap_register_table() in platform-specific 170 * code, then lets the common initarm() call this function with a NULL pointer. 171 */ 172void 173arm_devmap_bootstrap(vm_offset_t l1pt, const struct arm_devmap_entry *table) 174{ 175 const struct arm_devmap_entry *pd; 176 177 devmap_bootstrap_done = true; 178 179 /* 180 * If given a table pointer, use it. Otherwise, if a table was 181 * previously registered, use it. Otherwise, no work to do. 182 */ 183 if (table != NULL) 184 devmap_table = table; 185 else if (devmap_table == NULL) 186 return; 187 188 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 189 pmap_map_chunk(l1pt, pd->pd_va, pd->pd_pa, pd->pd_size, 190 pd->pd_prot,pd->pd_cache); 191 } 192} 193 194/* 195 * Look up the given physical address in the static mapping data and return the 196 * corresponding virtual address, or NULL if not found. 197 */ 198void * 199arm_devmap_ptov(vm_paddr_t pa, vm_size_t size) 200{ 201 const struct arm_devmap_entry *pd; 202 203 if (devmap_table == NULL) 204 return (NULL); 205 206 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 207 if (pa >= pd->pd_pa && pa + size <= pd->pd_pa + pd->pd_size) 208 return ((void *)(pd->pd_va + (pa - pd->pd_pa))); 209 } 210 211 return (NULL); 212} 213 214/* 215 * Look up the given virtual address in the static mapping data and return the 216 * corresponding physical address, or DEVMAP_PADDR_NOTFOUND if not found. 217 */ 218vm_paddr_t 219arm_devmap_vtop(void * vpva, vm_size_t size) 220{ 221 const struct arm_devmap_entry *pd; 222 vm_offset_t va; 223 224 if (devmap_table == NULL) 225 return (DEVMAP_PADDR_NOTFOUND); 226 227 va = (vm_offset_t)vpva; 228 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 229 if (va >= pd->pd_va && va + size <= pd->pd_va + pd->pd_size) 230 return ((vm_paddr_t)(pd->pd_pa + (va - pd->pd_va))); 231 } 232 233 return (DEVMAP_PADDR_NOTFOUND); 234} 235 236/* 237 * Map a set of physical memory pages into the kernel virtual address space. 238 * Return a pointer to where it is mapped. 239 * 240 * This uses a pre-established static mapping if one exists for the requested 241 * range, otherwise it allocates kva space and maps the physical pages into it. 242 * 243 * This routine is intended to be used for mapping device memory, NOT real 244 * memory; the mapping type is inherently PTE_DEVICE in pmap_kenter_device(). 245 */ 246void * 247pmap_mapdev(vm_offset_t pa, vm_size_t size) 248{ 249 vm_offset_t va, tmpva, offset; 250 void * rva; 251 252 /* First look in the static mapping table. */ 253 if ((rva = arm_devmap_ptov(pa, size)) != NULL) 254 return (rva); 255 256 offset = pa & PAGE_MASK; 257 pa = trunc_page(pa); 258 size = round_page(size + offset); 259 260 va = kva_alloc(size); 261 if (!va) 262 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 263 264 for (tmpva = va; size > 0;) { 265 pmap_kenter_device(tmpva, pa); 266 size -= PAGE_SIZE; 267 tmpva += PAGE_SIZE; 268 pa += PAGE_SIZE; 269 } 270 271 return ((void *)(va + offset)); 272} 273 274/* 275 * Unmap device memory and free the kva space. 276 */ 277void 278pmap_unmapdev(vm_offset_t va, vm_size_t size) 279{ 280 vm_offset_t tmpva, offset; 281 vm_size_t origsize; 282 283 /* Nothing to do if we find the mapping in the static table. */ 284 if (arm_devmap_vtop((void*)va, size) != DEVMAP_PADDR_NOTFOUND) 285 return; 286 287 origsize = size; 288 offset = va & PAGE_MASK; 289 va = trunc_page(va); 290 size = round_page(size + offset); 291 292 for (tmpva = va; size > 0;) { 293 pmap_kremove(tmpva); 294 size -= PAGE_SIZE; 295 tmpva += PAGE_SIZE; 296 } 297 298 kva_free(va, origsize); 299} 300 301#ifdef DDB 302#include <ddb/ddb.h> 303 304DB_SHOW_COMMAND(devmap, db_show_devmap) 305{ 306 devmap_dump_table(db_printf); 307} 308 309#endif /* DDB */ 310 311