1 /*- 2 * Copyright (c) 1997, Stefan Esser <se@freebsd.org> 3 * Copyright (c) 2000, Michael Smith <msmith@freebsd.org> 4 * Copyright (c) 2000, BSDi 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bus.h> 35 #include <sys/lock.h> 36 #include <sys/kernel.h> 37 #include <sys/mutex.h> 38 #include <sys/sysctl.h> 39 #include <dev/pci/pcivar.h> 40 #include <dev/pci/pcireg.h> 41 #include <vm/vm.h> 42 #include <vm/pmap.h> 43 #include <machine/pci_cfgreg.h> 44 45 enum { 46 CFGMECH_NONE = 0, 47 CFGMECH_1, 48 CFGMECH_PCIE, 49 }; 50 51 static uint32_t pci_docfgregread(int bus, int slot, int func, int reg, 52 int bytes); 53 static int pciereg_cfgread(int bus, unsigned slot, unsigned func, 54 unsigned reg, unsigned bytes); 55 static void pciereg_cfgwrite(int bus, unsigned slot, unsigned func, 56 unsigned reg, int data, unsigned bytes); 57 static int pcireg_cfgread(int bus, int slot, int func, int reg, int bytes); 58 static void pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes); 59 60 SYSCTL_DECL(_hw_pci); 61 62 static int cfgmech; 63 static vm_offset_t pcie_base; 64 static int pcie_minbus, pcie_maxbus; 65 static uint32_t pcie_badslots; 66 static struct mtx pcicfg_mtx; 67 static int mcfg_enable = 1; 68 SYSCTL_INT(_hw_pci, OID_AUTO, mcfg, CTLFLAG_RDTUN, &mcfg_enable, 0, 69 "Enable support for PCI-e memory mapped config access"); 70 71 /* 72 * Initialise access to PCI configuration space 73 */ 74 int 75 pci_cfgregopen(void) 76 { 77 static int once = 0; 78 uint64_t pciebar; 79 uint16_t did, vid; 80 81 if (!once) { 82 mtx_init(&pcicfg_mtx, "pcicfg", NULL, MTX_SPIN); 83 once = 1; 84 } 85 86 if (cfgmech != CFGMECH_NONE) 87 return (1); 88 cfgmech = CFGMECH_1; 89 90 /* 91 * Grope around in the PCI config space to see if this is a 92 * chipset that is capable of doing memory-mapped config cycles. 93 * This also implies that it can do PCIe extended config cycles. 94 */ 95 96 /* Check for supported chipsets */ 97 vid = pci_cfgregread(0, 0, 0, PCIR_VENDOR, 2); 98 did = pci_cfgregread(0, 0, 0, PCIR_DEVICE, 2); 99 switch (vid) { 100 case 0x8086: 101 switch (did) { 102 case 0x3590: 103 case 0x3592: 104 /* Intel 7520 or 7320 */ 105 pciebar = pci_cfgregread(0, 0, 0, 0xce, 2) << 16; 106 pcie_cfgregopen(pciebar, 0, 255); 107 break; 108 case 0x2580: 109 case 0x2584: 110 case 0x2590: 111 /* Intel 915, 925, or 915GM */ 112 pciebar = pci_cfgregread(0, 0, 0, 0x48, 4); 113 pcie_cfgregopen(pciebar, 0, 255); 114 break; 115 } 116 } 117 118 return (1); 119 } 120 121 static uint32_t 122 pci_docfgregread(int bus, int slot, int func, int reg, int bytes) 123 { 124 125 if (cfgmech == CFGMECH_PCIE && 126 (bus >= pcie_minbus && bus <= pcie_maxbus) && 127 (bus != 0 || !(1 << slot & pcie_badslots))) 128 return (pciereg_cfgread(bus, slot, func, reg, bytes)); 129 else 130 return (pcireg_cfgread(bus, slot, func, reg, bytes)); 131 } 132 133 /* 134 * Read configuration space register 135 */ 136 u_int32_t 137 pci_cfgregread(int bus, int slot, int func, int reg, int bytes) 138 { 139 uint32_t line; 140 141 /* 142 * Some BIOS writers seem to want to ignore the spec and put 143 * 0 in the intline rather than 255 to indicate none. Some use 144 * numbers in the range 128-254 to indicate something strange and 145 * apparently undocumented anywhere. Assume these are completely bogus 146 * and map them to 255, which the rest of the PCI code recognizes as 147 * as an invalid IRQ. 148 */ 149 if (reg == PCIR_INTLINE && bytes == 1) { 150 line = pci_docfgregread(bus, slot, func, PCIR_INTLINE, 1); 151 if (line == 0 || line >= 128) 152 line = PCI_INVALID_IRQ; 153 return (line); 154 } 155 return (pci_docfgregread(bus, slot, func, reg, bytes)); 156 } 157 158 /* 159 * Write configuration space register 160 */ 161 void 162 pci_cfgregwrite(int bus, int slot, int func, int reg, u_int32_t data, int bytes) 163 { 164 165 if (cfgmech == CFGMECH_PCIE && 166 (bus >= pcie_minbus && bus <= pcie_maxbus) && 167 (bus != 0 || !(1 << slot & pcie_badslots))) 168 pciereg_cfgwrite(bus, slot, func, reg, data, bytes); 169 else 170 pcireg_cfgwrite(bus, slot, func, reg, data, bytes); 171 } 172 173 /* 174 * Configuration space access using direct register operations 175 */ 176 177 /* enable configuration space accesses and return data port address */ 178 static int 179 pci_cfgenable(unsigned bus, unsigned slot, unsigned func, int reg, int bytes) 180 { 181 int dataport = 0; 182 183 if (bus <= PCI_BUSMAX && slot <= PCI_SLOTMAX && func <= PCI_FUNCMAX && 184 (unsigned)reg <= PCI_REGMAX && bytes != 3 && 185 (unsigned)bytes <= 4 && (reg & (bytes - 1)) == 0) { 186 outl(CONF1_ADDR_PORT, (1U << 31) | (bus << 16) | (slot << 11) 187 | (func << 8) | (reg & ~0x03)); 188 dataport = CONF1_DATA_PORT + (reg & 0x03); 189 } 190 return (dataport); 191 } 192 193 /* disable configuration space accesses */ 194 static void 195 pci_cfgdisable(void) 196 { 197 198 /* 199 * Do nothing. Writing a 0 to the address port can apparently 200 * confuse some bridges and cause spurious access failures. 201 */ 202 } 203 204 static int 205 pcireg_cfgread(int bus, int slot, int func, int reg, int bytes) 206 { 207 int data = -1; 208 int port; 209 210 mtx_lock_spin(&pcicfg_mtx); 211 port = pci_cfgenable(bus, slot, func, reg, bytes); 212 if (port != 0) { 213 switch (bytes) { 214 case 1: 215 data = inb(port); 216 break; 217 case 2: 218 data = inw(port); 219 break; 220 case 4: 221 data = inl(port); 222 break; 223 } 224 pci_cfgdisable(); 225 } 226 mtx_unlock_spin(&pcicfg_mtx); 227 return (data); 228 } 229 230 static void 231 pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes) 232 { 233 int port; 234 235 mtx_lock_spin(&pcicfg_mtx); 236 port = pci_cfgenable(bus, slot, func, reg, bytes); 237 if (port != 0) { 238 switch (bytes) { 239 case 1: 240 outb(port, data); 241 break; 242 case 2: 243 outw(port, data); 244 break; 245 case 4: 246 outl(port, data); 247 break; 248 } 249 pci_cfgdisable(); 250 } 251 mtx_unlock_spin(&pcicfg_mtx); 252 } 253 254 int 255 pcie_cfgregopen(uint64_t base, uint8_t minbus, uint8_t maxbus) 256 { 257 uint32_t val1, val2; 258 int slot; 259 260 if (!mcfg_enable) 261 return (0); 262 263 if (minbus != 0) 264 return (0); 265 266 if (bootverbose) 267 printf("PCIe: Memory Mapped configuration base @ 0x%lx\n", 268 base); 269 270 /* XXX: We should make sure this really fits into the direct map. */ 271 pcie_base = (vm_offset_t)pmap_mapdev(base, (maxbus + 1) << 20); 272 pcie_minbus = minbus; 273 pcie_maxbus = maxbus; 274 cfgmech = CFGMECH_PCIE; 275 276 /* 277 * On some AMD systems, some of the devices on bus 0 are 278 * inaccessible using memory-mapped PCI config access. Walk 279 * bus 0 looking for such devices. For these devices, we will 280 * fall back to using type 1 config access instead. 281 */ 282 if (pci_cfgregopen() != 0) { 283 for (slot = 0; slot <= PCI_SLOTMAX; slot++) { 284 val1 = pcireg_cfgread(0, slot, 0, 0, 4); 285 if (val1 == 0xffffffff) 286 continue; 287 288 val2 = pciereg_cfgread(0, slot, 0, 0, 4); 289 if (val2 != val1) 290 pcie_badslots |= (1 << slot); 291 } 292 } 293 294 return (1); 295 } 296 297 #define PCIE_VADDR(base, reg, bus, slot, func) \ 298 ((base) + \ 299 ((((bus) & 0xff) << 20) | \ 300 (((slot) & 0x1f) << 15) | \ 301 (((func) & 0x7) << 12) | \ 302 ((reg) & 0xfff))) 303 304 /* 305 * AMD BIOS And Kernel Developer's Guides for CPU families starting with 10h 306 * have a requirement that all accesses to the memory mapped PCI configuration 307 * space are done using AX class of registers. 308 * Since other vendors do not currently have any contradicting requirements 309 * the AMD access pattern is applied universally. 310 */ 311 312 static int 313 pciereg_cfgread(int bus, unsigned slot, unsigned func, unsigned reg, 314 unsigned bytes) 315 { 316 vm_offset_t va; 317 int data = -1; 318 319 if (bus < pcie_minbus || bus > pcie_maxbus || slot > PCI_SLOTMAX || 320 func > PCI_FUNCMAX || reg > PCIE_REGMAX) 321 return (-1); 322 323 va = PCIE_VADDR(pcie_base, reg, bus, slot, func); 324 325 switch (bytes) { 326 case 4: 327 __asm("movl %1, %0" : "=a" (data) 328 : "m" (*(volatile uint32_t *)va)); 329 break; 330 case 2: 331 __asm("movzwl %1, %0" : "=a" (data) 332 : "m" (*(volatile uint16_t *)va)); 333 break; 334 case 1: 335 __asm("movzbl %1, %0" : "=a" (data) 336 : "m" (*(volatile uint8_t *)va)); 337 break; 338 } 339 340 return (data); 341 } 342 343 static void 344 pciereg_cfgwrite(int bus, unsigned slot, unsigned func, unsigned reg, int data, 345 unsigned bytes) 346 { 347 vm_offset_t va; 348 349 if (bus < pcie_minbus || bus > pcie_maxbus || slot > PCI_SLOTMAX || 350 func > PCI_FUNCMAX || reg > PCIE_REGMAX) 351 return; 352 353 va = PCIE_VADDR(pcie_base, reg, bus, slot, func); 354 355 switch (bytes) { 356 case 4: 357 __asm("movl %1, %0" : "=m" (*(volatile uint32_t *)va) 358 : "a" (data)); 359 break; 360 case 2: 361 __asm("movw %1, %0" : "=m" (*(volatile uint16_t *)va) 362 : "a" ((uint16_t)data)); 363 break; 364 case 1: 365 __asm("movb %1, %0" : "=m" (*(volatile uint8_t *)va) 366 : "a" ((uint8_t)data)); 367 break; 368 } 369 } 370