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("$FreeBSD$"); 29 30 /* Routines for mapping device memory. */ 31 32 #include "opt_ddb.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/devmap.h> 37 #include <vm/vm.h> 38 #include <vm/vm_extern.h> 39 #include <vm/pmap.h> 40 #include <machine/vmparam.h> 41 42 static const struct devmap_entry *devmap_table; 43 static boolean_t devmap_bootstrap_done = false; 44 45 /* 46 * The allocated-kva (akva) devmap table and metadata. Platforms can call 47 * devmap_add_entry() to add static device mappings to this table using 48 * automatically allocated virtual addresses carved out of the top of kva space. 49 * Allocation begins immediately below the max kernel virtual address. 50 */ 51 #define AKVA_DEVMAP_MAX_ENTRIES 32 52 static struct devmap_entry akva_devmap_entries[AKVA_DEVMAP_MAX_ENTRIES]; 53 static u_int akva_devmap_idx; 54 static vm_offset_t akva_devmap_vaddr = DEVMAP_MAX_VADDR; 55 56 #if defined(__aarch64__) || defined(__riscv) 57 extern int early_boot; 58 #endif 59 60 /* 61 * Print the contents of the static mapping table using the provided printf-like 62 * output function (which will be either printf or db_printf). 63 */ 64 static void 65 devmap_dump_table(int (*prfunc)(const char *, ...)) 66 { 67 const struct devmap_entry *pd; 68 69 if (devmap_table == NULL || devmap_table[0].pd_size == 0) { 70 prfunc("No static device mappings.\n"); 71 return; 72 } 73 74 prfunc("Static device mappings:\n"); 75 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 76 prfunc(" 0x%08jx - 0x%08jx mapped at VA 0x%08jx\n", 77 pd->pd_pa, pd->pd_pa + pd->pd_size - 1, 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() 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() 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 #if __ARM_ARCH >= 6 195 pmap_preboot_map_attr(pd->pd_pa, pd->pd_va, pd->pd_size, 196 VM_PROT_READ | VM_PROT_WRITE, VM_MEMATTR_DEVICE); 197 #else 198 pmap_map_chunk(l1pt, pd->pd_va, pd->pd_pa, pd->pd_size, 199 VM_PROT_READ | VM_PROT_WRITE, PTE_DEVICE); 200 #endif 201 #elif defined(__aarch64__) || defined(__riscv) 202 pmap_kenter_device(pd->pd_va, pd->pd_size, pd->pd_pa); 203 #endif 204 } 205 } 206 207 /* 208 * Look up the given physical address in the static mapping data and return the 209 * corresponding virtual address, or NULL if not found. 210 */ 211 void * 212 devmap_ptov(vm_paddr_t pa, vm_size_t size) 213 { 214 const struct devmap_entry *pd; 215 216 if (devmap_table == NULL) 217 return (NULL); 218 219 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 220 if (pa >= pd->pd_pa && pa + size <= pd->pd_pa + pd->pd_size) 221 return ((void *)(pd->pd_va + (pa - pd->pd_pa))); 222 } 223 224 return (NULL); 225 } 226 227 /* 228 * Look up the given virtual address in the static mapping data and return the 229 * corresponding physical address, or DEVMAP_PADDR_NOTFOUND if not found. 230 */ 231 vm_paddr_t 232 devmap_vtop(void * vpva, vm_size_t size) 233 { 234 const struct devmap_entry *pd; 235 vm_offset_t va; 236 237 if (devmap_table == NULL) 238 return (DEVMAP_PADDR_NOTFOUND); 239 240 va = (vm_offset_t)vpva; 241 for (pd = devmap_table; pd->pd_size != 0; ++pd) { 242 if (va >= pd->pd_va && va + size <= pd->pd_va + pd->pd_size) 243 return ((vm_paddr_t)(pd->pd_pa + (va - pd->pd_va))); 244 } 245 246 return (DEVMAP_PADDR_NOTFOUND); 247 } 248 249 /* 250 * Map a set of physical memory pages into the kernel virtual address space. 251 * Return a pointer to where it is mapped. 252 * 253 * This uses a pre-established static mapping if one exists for the requested 254 * range, otherwise it allocates kva space and maps the physical pages into it. 255 * 256 * This routine is intended to be used for mapping device memory, NOT real 257 * memory; the mapping type is inherently VM_MEMATTR_DEVICE in 258 * pmap_kenter_device(). 259 */ 260 void * 261 pmap_mapdev(vm_offset_t pa, vm_size_t size) 262 { 263 vm_offset_t va, offset; 264 void * rva; 265 266 /* First look in the static mapping table. */ 267 if ((rva = devmap_ptov(pa, size)) != NULL) 268 return (rva); 269 270 offset = pa & PAGE_MASK; 271 pa = trunc_page(pa); 272 size = round_page(size + offset); 273 274 #if defined(__aarch64__) || defined(__riscv) 275 if (early_boot) { 276 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size); 277 va = akva_devmap_vaddr; 278 KASSERT(va >= VM_MAX_KERNEL_ADDRESS - L2_SIZE, 279 ("Too many early devmap mappings")); 280 } else 281 #endif 282 va = kva_alloc(size); 283 if (!va) 284 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 285 286 pmap_kenter_device(va, size, pa); 287 288 return ((void *)(va + offset)); 289 } 290 291 #if defined(__aarch64__) 292 void * 293 pmap_mapdev_attr(vm_offset_t pa, vm_size_t size, vm_memattr_t ma) 294 { 295 vm_offset_t va, offset; 296 void * rva; 297 298 /* First look in the static mapping table. */ 299 if ((rva = devmap_ptov(pa, size)) != NULL) 300 return (rva); 301 302 offset = pa & PAGE_MASK; 303 pa = trunc_page(pa); 304 size = round_page(size + offset); 305 306 if (early_boot) { 307 akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size); 308 va = akva_devmap_vaddr; 309 KASSERT(va >= (VM_MAX_KERNEL_ADDRESS - (PMAP_MAPDEV_EARLY_SIZE)), 310 ("Too many early devmap mappings 2")); 311 } else 312 va = kva_alloc(size); 313 if (!va) 314 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 315 316 pmap_kenter(va, size, pa, ma); 317 318 return ((void *)(va + offset)); 319 } 320 #endif 321 322 /* 323 * Unmap device memory and free the kva space. 324 */ 325 void 326 pmap_unmapdev(vm_offset_t va, vm_size_t size) 327 { 328 vm_offset_t offset; 329 330 /* Nothing to do if we find the mapping in the static table. */ 331 if (devmap_vtop((void*)va, size) != DEVMAP_PADDR_NOTFOUND) 332 return; 333 334 offset = va & PAGE_MASK; 335 va = trunc_page(va); 336 size = round_page(size + offset); 337 338 pmap_kremove_device(va, size); 339 kva_free(va, size); 340 } 341 342 #ifdef DDB 343 #include <ddb/ddb.h> 344 345 DB_SHOW_COMMAND(devmap, db_show_devmap) 346 { 347 devmap_dump_table(db_printf); 348 } 349 350 #endif /* DDB */ 351