| 1 | /* $NetBSD: xen_intr.c,v 1.9 2009/01/16 20:16:47 jym Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1998, 2001 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Charles M. Hannum, and by Jason R. Thorpe. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | #include <sys/cdefs.h> |
| 33 | __KERNEL_RCSID(0, "$NetBSD: xen_intr.c,v 1.9 2009/01/16 20:16:47 jym Exp $" ); |
| 34 | |
| 35 | #include <sys/param.h> |
| 36 | |
| 37 | #include <machine/cpu.h> |
| 38 | #include <machine/intr.h> |
| 39 | |
| 40 | /* |
| 41 | * Add a mask to cpl, and return the old value of cpl. |
| 42 | */ |
| 43 | int |
| 44 | splraise(int nlevel) |
| 45 | { |
| 46 | int olevel; |
| 47 | struct cpu_info *ci = curcpu(); |
| 48 | |
| 49 | olevel = ci->ci_ilevel; |
| 50 | if (nlevel > olevel) |
| 51 | ci->ci_ilevel = nlevel; |
| 52 | __insn_barrier(); |
| 53 | return (olevel); |
| 54 | } |
| 55 | |
| 56 | /* |
| 57 | * Restore a value to cpl (unmasking interrupts). If any unmasked |
| 58 | * interrupts are pending, call Xspllower() to process them. |
| 59 | */ |
| 60 | void |
| 61 | spllower(int nlevel) |
| 62 | { |
| 63 | struct cpu_info *ci = curcpu(); |
| 64 | uint32_t imask; |
| 65 | u_long psl; |
| 66 | |
| 67 | if (ci->ci_ilevel <= nlevel) |
| 68 | return; |
| 69 | |
| 70 | __insn_barrier(); |
| 71 | |
| 72 | imask = IUNMASK(ci, nlevel); |
| 73 | psl = x86_read_psl(); |
| 74 | x86_disable_intr(); |
| 75 | if (ci->ci_ipending & imask) { |
| 76 | KASSERT(psl == 0); |
| 77 | Xspllower(nlevel); |
| 78 | /* Xspllower does enable_intr() */ |
| 79 | } else { |
| 80 | ci->ci_ilevel = nlevel; |
| 81 | x86_write_psl(psl); |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | void |
| 86 | x86_disable_intr(void) |
| 87 | { |
| 88 | __cli(); |
| 89 | } |
| 90 | |
| 91 | void |
| 92 | x86_enable_intr(void) |
| 93 | { |
| 94 | __sti(); |
| 95 | } |
| 96 | |
| 97 | u_long |
| 98 | x86_read_psl(void) |
| 99 | { |
| 100 | |
| 101 | return (curcpu()->ci_vcpu->evtchn_upcall_mask); |
| 102 | } |
| 103 | |
| 104 | void |
| 105 | x86_write_psl(u_long psl) |
| 106 | { |
| 107 | struct cpu_info *ci = curcpu(); |
| 108 | |
| 109 | ci->ci_vcpu->evtchn_upcall_mask = psl; |
| 110 | xen_rmb(); |
| 111 | if (ci->ci_vcpu->evtchn_upcall_pending && psl == 0) { |
| 112 | hypervisor_force_callback(); |
| 113 | } |
| 114 | } |
| 115 | |