usr.sbin/bhyve/pci_irq.c

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