1 /* $NetBSD: userret.h,v 1.18 2011/02/17 13:53:32 matt Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 5 * Copyright (C) 1995, 1996 TooLs GmbH. 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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by TooLs GmbH. 19 * 4. The name of TooLs GmbH may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include "opt_ppcarch.h" 35 #include "opt_altivec.h" 36 37 #include <sys/userret.h> 38 39 #include <powerpc/fpu.h> 40 41 #ifdef PPC_BOOKE 42 #include <powerpc/spr.h> 43 #include <powerpc/booke/spr.h> 44 #endif 45 46 /* 47 * Define the code needed before returning to user mode, for 48 * trap and syscall. 49 */ 50 static __inline void 51 userret(struct lwp *l, struct trapframe *tf) 52 { 53 #if defined(PPC_HAVE_FPU) || defined(ALTIVEC) || defined(PPC_HAVE_SPE) 54 struct cpu_info * const ci = curcpu(); 55 #endif 56 57 KASSERTMSG((tf == trapframe(curlwp)), 58 ("tf=%p, trapframe(curlwp)=%p\n", tf, trapframe(curlwp))); 59 60 /* Invoke MI userret code */ 61 mi_userret(l); 62 63 tf->tf_srr1 &= PSL_USERSRR1; /* clear SRR1 status bits */ 64 65 /* 66 * If someone stole the fp or vector unit while we were away, 67 * disable it. Note that if the PSL FP/VEC bits aren't set, then 68 * we don't own it. 69 */ 70 #ifdef PPC_HAVE_FPU 71 if ((tf->tf_srr1 & PSL_FP) && 72 (l != ci->ci_fpulwp || l->l_md.md_fpucpu != ci)) { 73 tf->tf_srr1 &= ~(PSL_FP|PSL_FE0|PSL_FE1); 74 } 75 #endif 76 #ifdef ALTIVEC 77 /* 78 * We need to manually restore PSL_VEC each time we return 79 * to user mode since PSL_VEC is not preserved in SRR1. 80 */ 81 if (tf->tf_srr1 & PSL_VEC) { 82 if (l != ci->ci_veclwp) 83 tf->tf_srr1 &= ~PSL_VEC; 84 } else { 85 if (l == ci->ci_veclwp) 86 tf->tf_srr1 |= PSL_VEC; 87 } 88 89 /* 90 * If the new process isn't the current AltiVec process on this 91 * CPU, we need to stop any data streams that are active (since 92 * it will be a different address space). 93 */ 94 if (ci->ci_veclwp != NULL && ci->ci_veclwp != l) { 95 __asm volatile("dssall;sync"); 96 } 97 #endif 98 #ifdef PPC_BOOKE 99 /* 100 * BookE doesn't PSL_SE but it does have a debug instruction completion 101 * exception but it needs PSL_DE to fire. Since we don't want it to 102 * happen in the kernel, we must disable PSL_DE and let it get 103 * restored by rfi/rfci. 104 */ 105 if (__predict_false(tf->tf_srr1 & PSL_SE)) { 106 extern void booke_sstep(struct trapframe *); /* ugly */ 107 booke_sstep(tf); 108 } 109 #endif 110 #ifdef PPC_HAVE_SPE 111 /* 112 * We need to manually restore PSL_SPV each time we return 113 * to user mode since PSL_SPV is not preserved in SRR1 since 114 * we don't include it in PSL_USERSRR1 to control its setting. 115 */ 116 if (tf->tf_srr1 & PSL_SPV) { 117 if (l != ci->ci_veclwp) 118 tf->tf_srr1 &= ~PSL_SPV; 119 } else { 120 if (l == ci->ci_veclwp) 121 tf->tf_srr1 |= PSL_SPV; 122 } 123 #endif 124 } 125