1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2014 Hudson River Trading LLC 5 * Written by: John H. Baldwin <jhb@FreeBSD.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following 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 AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 31 #include <sys/cdefs.h> 32 #include <sys/param.h> 33 #include <machine/vmm.h> 34 35 #include <assert.h> 36 #include <pthread.h> 37 #include <stdbool.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <vmmapi.h> 41 42 #include "acpi.h" 43 #include "inout.h" 44 #include "pci_emul.h" 45 #include "pci_irq.h" 46 #include "pci_lpc.h" 47 48 /* 49 * Implement an 8 pin PCI interrupt router compatible with the router 50 * present on Intel's ICH10 chip. 51 */ 52 53 /* Fields in each PIRQ register. */ 54 #define PIRQ_DIS 0x80 55 #define PIRQ_IRQ 0x0f 56 57 /* Only IRQs 3-7, 9-12, and 14-15 are permitted. */ 58 #define PERMITTED_IRQS 0xdef8 59 #define IRQ_PERMITTED(irq) (((1U << (irq)) & PERMITTED_IRQS) != 0) 60 61 /* IRQ count to disable an IRQ. */ 62 #define IRQ_DISABLED 0xff 63 64 #define NPIRQS 8 65 static struct pirq { 66 uint8_t reg; 67 int use_count; 68 int active_count; 69 pthread_mutex_t lock; 70 } pirqs[NPIRQS]; 71 72 #define NIRQ_COUNTS 16 73 static u_char irq_counts[NIRQ_COUNTS]; 74 static int pirq_cold = 1; 75 76 /* 77 * Returns true if this pin is enabled with a valid IRQ. Setting the 78 * register to a reserved IRQ causes interrupts to not be asserted as 79 * if the pin was disabled. 80 */ 81 static bool 82 pirq_valid_irq(int reg) 83 { 84 85 if (reg & PIRQ_DIS) 86 return (false); 87 return (IRQ_PERMITTED(reg & PIRQ_IRQ)); 88 } 89 90 uint8_t 91 pirq_read(int pin) 92 { 93 94 assert(pin > 0 && pin <= NPIRQS); 95 return (pirqs[pin - 1].reg); 96 } 97 98 void 99 pirq_write(struct vmctx *ctx, int pin, uint8_t val) 100 { 101 struct pirq *pirq; 102 103 assert(pin > 0 && pin <= NPIRQS); 104 pirq = &pirqs[pin - 1]; 105 pthread_mutex_lock(&pirq->lock); 106 if (pirq->reg != (val & (PIRQ_DIS | PIRQ_IRQ))) { 107 if (pirq->active_count != 0 && pirq_valid_irq(pirq->reg)) 108 vm_isa_deassert_irq(ctx, pirq->reg & PIRQ_IRQ, -1); 109 pirq->reg = val & (PIRQ_DIS | PIRQ_IRQ); 110 if (pirq->active_count != 0 && pirq_valid_irq(pirq->reg)) 111 vm_isa_assert_irq(ctx, pirq->reg & PIRQ_IRQ, -1); 112 } 113 pthread_mutex_unlock(&pirq->lock); 114 } 115 116 void 117 pci_irq_reserve(int irq) 118 { 119 120 assert(irq >= 0 && irq < NIRQ_COUNTS); 121 assert(pirq_cold); 122 assert(irq_counts[irq] == 0 || irq_counts[irq] == IRQ_DISABLED); 123 irq_counts[irq] = IRQ_DISABLED; 124 } 125 126 void 127 pci_irq_use(int irq) 128 { 129 130 assert(irq >= 0 && irq < NIRQ_COUNTS); 131 assert(pirq_cold); 132 assert(irq_counts[irq] != IRQ_DISABLED); 133 irq_counts[irq]++; 134 } 135 136 void 137 pci_irq_init(struct vmctx *ctx __unused) 138 { 139 int i; 140 141 for (i = 0; i < NPIRQS; i++) { 142 pirqs[i].reg = PIRQ_DIS; 143 pirqs[i].use_count = 0; 144 pirqs[i].active_count = 0; 145 pthread_mutex_init(&pirqs[i].lock, NULL); 146 } 147 for (i = 0; i < NIRQ_COUNTS; i++) { 148 if (IRQ_PERMITTED(i)) 149 irq_counts[i] = 0; 150 else 151 irq_counts[i] = IRQ_DISABLED; 152 } 153 } 154 155 void 156 pci_irq_assert(struct pci_devinst *pi) 157 { 158 struct pirq *pirq; 159 int pin; 160 161 pin = pi->pi_lintr.pirq_pin; 162 if (pin > 0) { 163 assert(pin <= NPIRQS); 164 pirq = &pirqs[pin - 1]; 165 pthread_mutex_lock(&pirq->lock); 166 pirq->active_count++; 167 if (pirq->active_count == 1 && pirq_valid_irq(pirq->reg)) { 168 vm_isa_assert_irq(pi->pi_vmctx, pirq->reg & PIRQ_IRQ, 169 pi->pi_lintr.ioapic_irq); 170 pthread_mutex_unlock(&pirq->lock); 171 return; 172 } 173 pthread_mutex_unlock(&pirq->lock); 174 } 175 vm_ioapic_assert_irq(pi->pi_vmctx, pi->pi_lintr.ioapic_irq); 176 } 177 178 void 179 pci_irq_deassert(struct pci_devinst *pi) 180 { 181 struct pirq *pirq; 182 int pin; 183 184 pin = pi->pi_lintr.pirq_pin; 185 if (pin > 0) { 186 assert(pin <= NPIRQS); 187 pirq = &pirqs[pin - 1]; 188 pthread_mutex_lock(&pirq->lock); 189 pirq->active_count--; 190 if (pirq->active_count == 0 && pirq_valid_irq(pirq->reg)) { 191 vm_isa_deassert_irq(pi->pi_vmctx, pirq->reg & PIRQ_IRQ, 192 pi->pi_lintr.ioapic_irq); 193 pthread_mutex_unlock(&pirq->lock); 194 return; 195 } 196 pthread_mutex_unlock(&pirq->lock); 197 } 198 vm_ioapic_deassert_irq(pi->pi_vmctx, pi->pi_lintr.ioapic_irq); 199 } 200 201 int 202 pirq_alloc_pin(struct pci_devinst *pi) 203 { 204 struct vmctx *ctx = pi->pi_vmctx; 205 int best_count, best_irq, best_pin, irq, pin; 206 207 pirq_cold = 0; 208 209 if (lpc_bootrom()) { 210 /* For external bootrom use fixed mapping. */ 211 best_pin = (4 + pi->pi_slot + pi->pi_lintr.pin) % 8; 212 } else { 213 /* Find the least-used PIRQ pin. */ 214 best_pin = 0; 215 best_count = pirqs[0].use_count; 216 for (pin = 1; pin < NPIRQS; pin++) { 217 if (pirqs[pin].use_count < best_count) { 218 best_pin = pin; 219 best_count = pirqs[pin].use_count; 220 } 221 } 222 } 223 pirqs[best_pin].use_count++; 224 225 /* Second, route this pin to an IRQ. */ 226 if (pirqs[best_pin].reg == PIRQ_DIS) { 227 best_irq = -1; 228 best_count = 0; 229 for (irq = 0; irq < NIRQ_COUNTS; irq++) { 230 if (irq_counts[irq] == IRQ_DISABLED) 231 continue; 232 if (best_irq == -1 || irq_counts[irq] < best_count) { 233 best_irq = irq; 234 best_count = irq_counts[irq]; 235 } 236 } 237 assert(best_irq >= 0); 238 irq_counts[best_irq]++; 239 pirqs[best_pin].reg = best_irq; 240 vm_isa_set_irq_trigger(ctx, best_irq, LEVEL_TRIGGER); 241 } 242 243 return (best_pin + 1); 244 } 245 246 int 247 pirq_irq(int pin) 248 { 249 assert(pin > 0 && pin <= NPIRQS); 250 return (pirqs[pin - 1].reg & PIRQ_IRQ); 251 } 252 253 /* XXX: Generate $PIR table. */ 254 255 static void 256 pirq_dsdt(void) 257 { 258 char *irq_prs, *old; 259 int irq, pin; 260 261 irq_prs = NULL; 262 for (irq = 0; irq < NIRQ_COUNTS; irq++) { 263 if (!IRQ_PERMITTED(irq)) 264 continue; 265 if (irq_prs == NULL) 266 asprintf(&irq_prs, "%d", irq); 267 else { 268 old = irq_prs; 269 asprintf(&irq_prs, "%s,%d", old, irq); 270 free(old); 271 } 272 } 273 274 /* 275 * A helper method to validate a link register's value. This 276 * duplicates pirq_valid_irq(). 277 */ 278 dsdt_line(""); 279 dsdt_line("Method (PIRV, 1, NotSerialized)"); 280 dsdt_line("{"); 281 dsdt_line(" If (And (Arg0, 0x%02X))", PIRQ_DIS); 282 dsdt_line(" {"); 283 dsdt_line(" Return (0x00)"); 284 dsdt_line(" }"); 285 dsdt_line(" And (Arg0, 0x%02X, Local0)", PIRQ_IRQ); 286 dsdt_line(" If (LLess (Local0, 0x03))"); 287 dsdt_line(" {"); 288 dsdt_line(" Return (0x00)"); 289 dsdt_line(" }"); 290 dsdt_line(" If (LEqual (Local0, 0x08))"); 291 dsdt_line(" {"); 292 dsdt_line(" Return (0x00)"); 293 dsdt_line(" }"); 294 dsdt_line(" If (LEqual (Local0, 0x0D))"); 295 dsdt_line(" {"); 296 dsdt_line(" Return (0x00)"); 297 dsdt_line(" }"); 298 dsdt_line(" Return (0x01)"); 299 dsdt_line("}"); 300 301 for (pin = 0; pin < NPIRQS; pin++) { 302 dsdt_line(""); 303 dsdt_line("Device (LNK%c)", 'A' + pin); 304 dsdt_line("{"); 305 dsdt_line(" Name (_HID, EisaId (\"PNP0C0F\"))"); 306 dsdt_line(" Name (_UID, 0x%02X)", pin + 1); 307 dsdt_line(" Method (_STA, 0, NotSerialized)"); 308 dsdt_line(" {"); 309 dsdt_line(" If (PIRV (PIR%c))", 'A' + pin); 310 dsdt_line(" {"); 311 dsdt_line(" Return (0x0B)"); 312 dsdt_line(" }"); 313 dsdt_line(" Else"); 314 dsdt_line(" {"); 315 dsdt_line(" Return (0x09)"); 316 dsdt_line(" }"); 317 dsdt_line(" }"); 318 dsdt_line(" Name (_PRS, ResourceTemplate ()"); 319 dsdt_line(" {"); 320 dsdt_line(" IRQ (Level, ActiveLow, Shared, )"); 321 dsdt_line(" {%s}", irq_prs); 322 dsdt_line(" })"); 323 dsdt_line(" Name (CB%02X, ResourceTemplate ()", pin + 1); 324 dsdt_line(" {"); 325 dsdt_line(" IRQ (Level, ActiveLow, Shared, )"); 326 dsdt_line(" {}"); 327 dsdt_line(" })"); 328 dsdt_line(" CreateWordField (CB%02X, 0x01, CIR%c)", 329 pin + 1, 'A' + pin); 330 dsdt_line(" Method (_CRS, 0, NotSerialized)"); 331 dsdt_line(" {"); 332 dsdt_line(" And (PIR%c, 0x%02X, Local0)", 'A' + pin, 333 PIRQ_DIS | PIRQ_IRQ); 334 dsdt_line(" If (PIRV (Local0))"); 335 dsdt_line(" {"); 336 dsdt_line(" ShiftLeft (0x01, Local0, CIR%c)", 'A' + pin); 337 dsdt_line(" }"); 338 dsdt_line(" Else"); 339 dsdt_line(" {"); 340 dsdt_line(" Store (0x00, CIR%c)", 'A' + pin); 341 dsdt_line(" }"); 342 dsdt_line(" Return (CB%02X)", pin + 1); 343 dsdt_line(" }"); 344 dsdt_line(" Method (_DIS, 0, NotSerialized)"); 345 dsdt_line(" {"); 346 dsdt_line(" Store (0x80, PIR%c)", 'A' + pin); 347 dsdt_line(" }"); 348 dsdt_line(" Method (_SRS, 1, NotSerialized)"); 349 dsdt_line(" {"); 350 dsdt_line(" CreateWordField (Arg0, 0x01, SIR%c)", 'A' + pin); 351 dsdt_line(" FindSetRightBit (SIR%c, Local0)", 'A' + pin); 352 dsdt_line(" Store (Decrement (Local0), PIR%c)", 'A' + pin); 353 dsdt_line(" }"); 354 dsdt_line("}"); 355 } 356 free(irq_prs); 357 } 358 LPC_DSDT(pirq_dsdt); 359