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 #include <sys/cdefs.h>
31
32 #include <sys/types.h>
33 #include <stdio.h>
34
35 #include <machine/vmm.h>
36 #include <vmmapi.h>
37
38 #include "ioapic.h"
39 #include "pci_emul.h"
40 #include "pci_lpc.h"
41
42 /*
43 * Assign PCI INTx interrupts to I/O APIC pins in a round-robin
44 * fashion. Note that we have no idea what the HPET is using, but the
45 * HPET is also programmable whereas this is intended for hardwired
46 * PCI interrupts.
47 *
48 * This assumes a single I/O APIC where pins >= 16 are permitted for
49 * PCI devices.
50 */
51 static int pci_pins;
52
53 void
ioapic_init(struct vmctx * ctx)54 ioapic_init(struct vmctx *ctx)
55 {
56
57 if (vm_ioapic_pincount(ctx, &pci_pins) < 0) {
58 pci_pins = 0;
59 return;
60 }
61
62 /* Ignore the first 16 pins. */
63 if (pci_pins <= 16) {
64 pci_pins = 0;
65 return;
66 }
67 pci_pins -= 16;
68 }
69
70 int
ioapic_pci_alloc_irq(struct pci_devinst * pi)71 ioapic_pci_alloc_irq(struct pci_devinst *pi)
72 {
73 static int last_pin;
74
75 if (pci_pins == 0)
76 return (-1);
77 if (lpc_bootrom()) {
78 /* For external bootrom use fixed mapping. */
79 return (16 + (4 + pi->pi_slot + pi->pi_lintr.pin) % 8);
80 }
81 return (16 + (last_pin++ % pci_pins));
82 }
83