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 /* Routines for mapping device memory. */ 29 30 #include "opt_ddb.h" 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/devmap.h> 35 #include <vm/vm.h> 36 #include <vm/vm_extern.h> 37 #include <vm/pmap.h> 38 #include <machine/vmparam.h> 39 40 static const struct devmap_entry *devmap_table; 41 static boolean_t devmap_bootstrap_done = false; 42 43 /* 44 * The allocated-kva (akva) devmap table and metadata. Platforms can call 45 * devmap_add_entry() to add static device mappings to this table using 46 * automatically allocated virtual addresses carved out of the top of kva space. 47 * Allocation begins immediately below the max kernel virtual address. 48 */ 49 #define AKVA_DEVMAP_MAX_ENTRIES 32 50 static struct devmap_entry akva_devmap_entries[AKVA_DEVMAP_MAX_ENTRIES]; 51 static u_int akva_devmap_idx; 52 static vm_offset_t akva_devmap_vaddr = DEVMAP_MAX_VADDR; 53 54 #if defined(__aarch64__) || defined(__riscv) 55 extern int early_boot; 56 #endif 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 */ 62 static void 63 devmap_dump_table(int (*prfunc)(const char *, ...)) 64 { 65 const struct 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%08jx - 0x%08jx mapped at VA 0x%08jx\n", 75 (uintmax_t)pd->pd_pa, 76 (uintmax_t)(pd->pd_pa + pd->pd_size - 1), 77 (uintmax_t)pd->pd_va); 78 } 79 } 80 81 /* 82 * Print the contents of the static mapping table. Used for bootverbose. 83 */ 84 void 85 devmap_print_table(void) 86 { 87 devmap_dump_table(printf); 88 } 89 90 /* 91 * Return the "last" kva address used by the registered devmap table. It's 92 * actually the lowest address used by the static mappings, i.e., the address of 93 * the first unusable byte of KVA. 94 */ 95 vm_offset_t 96 devmap_lastaddr(void) 97 { 98 const struct devmap_entry *pd; 99 vm_offset_t lowaddr; 100 101 if (akva_devmap_idx > 0) 102 return (akva_devmap_vaddr); 103 104 lowaddr = DEVMAP_MAX_VADDR; 105 for (pd = devmap_table; pd != NULL && pd->pd_size != 0; ++pd) { 106 if (lowaddr > pd->pd_va) 107 lowaddr = pd->pd_va; 108 } 109 110 return (lowaddr); 111 } 112 113 /* 114 * Add an entry to the internal "akva" static devmap table using the given 115 * physical address and size and a virtual address allocated from the top of 116 * kva. This automatically registers the akva table on the first call, so all a 117 * platform has to do is call this routine to install as many mappings as it 118 * needs and when the platform-specific init function calls devmap_bootstrap() 119 * it will pick up all the entries in the akva table automatically. 120 */ 121 void 122 devmap_add_entry(vm_paddr_t pa, vm_size_t sz) 123 { 124 struct devmap_entry *m; 125 126 if (devmap_bootstrap_done) 127 panic("devmap_add_entry() after devmap_bootstrap()"); 128 129 if (akva_devmap_idx == (AKVA_DEVMAP_MAX_ENTRIES - 1)) 130 panic("AKVA_DEVMAP_MAX_ENTRIES is too small"); 131 132 if (akva_devmap_idx == 0) 133 devmap_register_table(akva_devmap_entries); 134 135 /* Allocate virtual address space from the top of kva downwards. */ 136 #ifdef __arm__ 137 /* 138 * If the range being mapped is aligned and sized to 1MB boundaries then 139 * also align the virtual address to the next-lower 1MB boundary so that 140 * we end with a nice efficient section mapping. 141 */ 142 if ((pa & 0x000fffff) == 0 && (sz & 0x000fffff) == 0) { 143 akva_devmap_vaddr = trunc_1mpage(akva_devmap_vaddr - sz); 144 } else 145 #endif 146 { 147 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - sz); 148 } 149 m = &akva_devmap_entries[akva_devmap_idx++]; 150 m->pd_va = akva_devmap_vaddr; 151 m->pd_pa = pa; 152 m->pd_size = sz; 153 } 154 155 /* 156 * Register the given table as the one to use in devmap_bootstrap(). 157 */ 158 void 159 devmap_register_table(const struct devmap_entry *table) 160 { 161 162 devmap_table = table; 163 } 164 165 /* 166 * Map all of the static regions in the devmap table, and remember the devmap 167 * table so the mapdev, ptov, and vtop functions can do lookups later. 168 * 169 * If a non-NULL table pointer is given it is used unconditionally, otherwise 170 * the previously-registered table is used. This smooths transition from legacy 171 * code that fills in a local table then calls this function passing that table, 172 * and newer code that uses devmap_register_table() in platform-specific 173 * code, then lets the common platform-specific init function call this function 174 * with a NULL pointer. 175 */ 176 void 177 devmap_bootstrap(vm_offset_t l1pt, const struct devmap_entry *table) 178 { 179 const struct devmap_entry *pd; 180 181 devmap_bootstrap_done = true; 182 183 /* 184 * If given a table pointer, use it. Otherwise, if a table was 185 * previously registered, use it. Otherwise, no work to do. 186 */ 187 if (table != NULL) 188 devmap_table = table; 189 else if (devmap_table == NULL) 190 return; 191 192 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 193 #if defined(__arm__) 194 pmap_preboot_map_attr(pd->pd_pa, pd->pd_va, pd->pd_size, 195 VM_PROT_READ | VM_PROT_WRITE, VM_MEMATTR_DEVICE); 196 #elif defined(__aarch64__) || defined(__riscv) 197 pmap_kenter_device(pd->pd_va, pd->pd_size, pd->pd_pa); 198 #endif 199 } 200 } 201 202 /* 203 * Look up the given physical address in the static mapping data and return the 204 * corresponding virtual address, or NULL if not found. 205 */ 206 void * 207 devmap_ptov(vm_paddr_t pa, vm_size_t size) 208 { 209 const struct devmap_entry *pd; 210 211 if (devmap_table == NULL) 212 return (NULL); 213 214 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 215 if (pa >= pd->pd_pa && pa + size <= pd->pd_pa + pd->pd_size) 216 return ((void *)(pd->pd_va + (pa - pd->pd_pa))); 217 } 218 219 return (NULL); 220 } 221 222 /* 223 * Look up the given virtual address in the static mapping data and return the 224 * corresponding physical address, or DEVMAP_PADDR_NOTFOUND if not found. 225 */ 226 vm_paddr_t 227 devmap_vtop(void * vpva, vm_size_t size) 228 { 229 const struct devmap_entry *pd; 230 vm_offset_t va; 231 232 if (devmap_table == NULL) 233 return (DEVMAP_PADDR_NOTFOUND); 234 235 va = (vm_offset_t)vpva; 236 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 237 if (va >= pd->pd_va && va + size <= pd->pd_va + pd->pd_size) 238 return ((vm_paddr_t)(pd->pd_pa + (va - pd->pd_va))); 239 } 240 241 return (DEVMAP_PADDR_NOTFOUND); 242 } 243 244 /* 245 * Map a set of physical memory pages into the kernel virtual address space. 246 * Return a pointer to where it is mapped. 247 * 248 * This uses a pre-established static mapping if one exists for the requested 249 * range, otherwise it allocates kva space and maps the physical pages into it. 250 * 251 * This routine is intended to be used for mapping device memory, NOT real 252 * memory; the mapping type is inherently VM_MEMATTR_DEVICE in 253 * pmap_kenter_device(). 254 */ 255 void * 256 pmap_mapdev(vm_paddr_t pa, vm_size_t size) 257 { 258 vm_offset_t va, offset; 259 void * rva; 260 261 /* First look in the static mapping table. */ 262 if ((rva = devmap_ptov(pa, size)) != NULL) 263 return (rva); 264 265 offset = pa & PAGE_MASK; 266 pa = trunc_page(pa); 267 size = round_page(size + offset); 268 269 #if defined(__aarch64__) || defined(__riscv) 270 if (early_boot) { 271 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size); 272 va = akva_devmap_vaddr; 273 KASSERT(va >= VM_MAX_KERNEL_ADDRESS - PMAP_MAPDEV_EARLY_SIZE, 274 ("Too many early devmap mappings")); 275 } else 276 #endif 277 #ifdef __aarch64__ 278 if (size >= L2_SIZE && (pa & L2_OFFSET) == 0) 279 va = kva_alloc_aligned(size, L2_SIZE); 280 else if (size >= L3C_SIZE && (pa & L3C_OFFSET) == 0) 281 va = kva_alloc_aligned(size, L3C_SIZE); 282 else 283 #endif 284 va = kva_alloc(size); 285 if (!va) 286 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 287 288 pmap_kenter_device(va, size, pa); 289 290 return ((void *)(va + offset)); 291 } 292 293 #if defined(__aarch64__) || defined(__riscv) 294 void * 295 pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, vm_memattr_t ma) 296 { 297 vm_offset_t va, offset; 298 void * rva; 299 300 /* First look in the static mapping table. */ 301 if ((rva = devmap_ptov(pa, size)) != NULL) 302 return (rva); 303 304 offset = pa & PAGE_MASK; 305 pa = trunc_page(pa); 306 size = round_page(size + offset); 307 308 if (early_boot) { 309 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size); 310 va = akva_devmap_vaddr; 311 KASSERT(va >= (VM_MAX_KERNEL_ADDRESS - (PMAP_MAPDEV_EARLY_SIZE)), 312 ("Too many early devmap mappings 2")); 313 } else 314 #ifdef __aarch64__ 315 if (size >= L2_SIZE && (pa & L2_OFFSET) == 0) 316 va = kva_alloc_aligned(size, L2_SIZE); 317 else if (size >= L3C_SIZE && (pa & L3C_OFFSET) == 0) 318 va = kva_alloc_aligned(size, L3C_SIZE); 319 else 320 #endif 321 va = kva_alloc(size); 322 if (!va) 323 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 324 325 pmap_kenter(va, size, pa, ma); 326 327 return ((void *)(va + offset)); 328 } 329 #endif 330 331 /* 332 * Unmap device memory and free the kva space. 333 */ 334 void 335 pmap_unmapdev(void *p, vm_size_t size) 336 { 337 vm_offset_t offset, va; 338 339 /* Nothing to do if we find the mapping in the static table. */ 340 if (devmap_vtop(p, size) != DEVMAP_PADDR_NOTFOUND) 341 return; 342 343 va = (vm_offset_t)p; 344 offset = va & PAGE_MASK; 345 va = trunc_page(va); 346 size = round_page(size + offset); 347 348 pmap_kremove_device(va, size); 349 kva_free(va, size); 350 } 351 352 #ifdef DDB 353 #include <ddb/ddb.h> 354 355 DB_SHOW_COMMAND_FLAGS(devmap, db_show_devmap, DB_CMD_MEMSAFE) 356 { 357 devmap_dump_table(db_printf); 358 } 359 360 #endif /* DDB */ 361