1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 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 __FBSDID("$FreeBSD$"); 32 33 #include <sys/types.h> 34 #include <stdio.h> 35 36 #include <machine/vmm.h> 37 #include <vmmapi.h> 38 39 #include "ioapic.h" 40 #include "pci_emul.h" 41 #include "pci_lpc.h" 42 43 /* 44 * Assign PCI INTx interrupts to I/O APIC pins in a round-robin 45 * fashion. Note that we have no idea what the HPET is using, but the 46 * HPET is also programmable whereas this is intended for hardwired 47 * PCI interrupts. 48 * 49 * This assumes a single I/O APIC where pins >= 16 are permitted for 50 * PCI devices. 51 */ 52 static int pci_pins; 53 54 void 55 ioapic_init(struct vmctx *ctx) 56 { 57 58 if (vm_ioapic_pincount(ctx, &pci_pins) < 0) { 59 pci_pins = 0; 60 return; 61 } 62 63 /* Ignore the first 16 pins. */ 64 if (pci_pins <= 16) { 65 pci_pins = 0; 66 return; 67 } 68 pci_pins -= 16; 69 } 70 71 int 72 ioapic_pci_alloc_irq(struct pci_devinst *pi) 73 { 74 static int last_pin; 75 76 if (pci_pins == 0) 77 return (-1); 78 if (lpc_bootrom()) { 79 /* For external bootrom use fixed mapping. */ 80 return (16 + (4 + pi->pi_slot + pi->pi_lintr.pin) % 8); 81 } 82 return (16 + (last_pin++ % pci_pins)); 83 } 84