1 /* $NetBSD: xen_intr.c,v 1.2 2007/11/22 16:17:05 bouyer 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: xen_intr.c,v 1.2 2007/11/22 16:17:05 bouyer Exp $"); 41 42 #include <sys/param.h> 43 44 #include <machine/cpu.h> 45 #include <machine/intr.h> 46 47 /* 48 * Add a mask to cpl, and return the old value of cpl. 49 */ 50 int 51 splraise(int nlevel) 52 { 53 int olevel; 54 struct cpu_info *ci = curcpu(); 55 56 olevel = ci->ci_ilevel; 57 if (nlevel > olevel) 58 ci->ci_ilevel = nlevel; 59 __insn_barrier(); 60 return (olevel); 61 } 62 63 /* 64 * Restore a value to cpl (unmasking interrupts). If any unmasked 65 * interrupts are pending, call Xspllower() to process them. 66 */ 67 void 68 spllower(int nlevel) 69 { 70 struct cpu_info *ci = curcpu(); 71 u_int32_t imask; 72 u_long psl; 73 74 __insn_barrier(); 75 76 imask = IUNMASK(ci, nlevel); 77 psl = x86_read_psl(); 78 x86_disable_intr(); 79 if (ci->ci_ipending & imask) { 80 Xspllower(nlevel); 81 /* Xspllower does enable_intr() */ 82 } else { 83 ci->ci_ilevel = nlevel; 84 x86_write_psl(psl); 85 } 86 } 87 88 #ifndef __x86_64__ 89 90 /* 91 * Software interrupt registration 92 * 93 * We hand-code this to ensure that it's atomic. 94 * 95 * XXX always scheduled on the current CPU. 96 */ 97 void 98 softintr(int sir) 99 { 100 struct cpu_info *ci = curcpu(); 101 102 __asm volatile("orl %1, %0" : "=m"(ci->ci_ipending) : "ir" (1 << sir)); 103 } 104 #endif 105 106 void 107 x86_disable_intr(void) 108 { 109 __cli(); 110 } 111 112 void 113 x86_enable_intr(void) 114 { 115 __sti(); 116 } 117 118 u_long 119 x86_read_psl(void) 120 { 121 122 return (HYPERVISOR_shared_info->vcpu_info[0].evtchn_upcall_mask); 123 } 124 125 void 126 x86_write_psl(u_long psl) 127 { 128 129 HYPERVISOR_shared_info->vcpu_info[0].evtchn_upcall_mask = psl; 130 x86_lfence(); 131 if (HYPERVISOR_shared_info->vcpu_info[0].evtchn_upcall_pending && 132 psl == 0) { 133 hypervisor_force_callback(); 134 } 135 } 136