1 /* $NetBSD: userret.h,v 1.31 2020/07/06 09:34:17 rin 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 #ifdef _KERNEL_OPT
35 #include "opt_altivec.h"
36 #include "opt_ppcarch.h"
37 #endif
38
39 #include <sys/userret.h>
40 #include <sys/ras.h>
41
42 #include <powerpc/fpu.h>
43 #include <powerpc/psl.h>
44
45 #ifdef PPC_BOOKE
46 #include <powerpc/spr.h>
47 #include <powerpc/booke/spr.h>
48 #endif
49
50 /*
51 * Define the code needed before returning to user mode, for
52 * trap and syscall.
53 */
54 static __inline void
userret(struct lwp * l,struct trapframe * tf)55 userret(struct lwp *l, struct trapframe *tf)
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 KASSERTMSG((tf->tf_srr1 & PSL_PR) != 0,
64 "tf=%p: srr1 (%#lx): PSL_PR isn't set!",
65 tf, tf->tf_srr1);
66 KASSERTMSG((tf->tf_srr1 & PSL_FP) == 0
67 || l->l_cpu->ci_data.cpu_pcu_curlwp[PCU_FPU] == l,
68 "tf=%p: srr1 (%#lx): PSL_FP set but FPU curlwp %p is not curlwp %p!",
69 tf, tf->tf_srr1, l->l_cpu->ci_data.cpu_pcu_curlwp[PCU_FPU], l);
70
71 /* clear SRR1 status bits */
72 tf->tf_srr1 &= (PSL_USERSRR1|PSL_FP|PSL_VEC);
73
74 #ifdef ALTIVEC
75 /*
76 * We need to manually restore PSL_VEC each time we return
77 * to user mode since PSL_VEC isn't always preserved in SRR1.
78 * We keep a copy of it in md_flags to make restoring easier.
79 */
80 tf->tf_srr1 |= l->l_md.md_flags & PSL_VEC;
81 #endif
82 #ifdef PPC_BOOKE
83 /*
84 * BookE doesn't have PSL_SE but it does have a debug instruction
85 * completion exception but it needs PSL_DE to fire. Instead we
86 * use IAC1/IAC2 to match the next PC.
87 */
88 if (__predict_false(tf->tf_srr1 & PSL_SE)) {
89 tf->tf_srr1 &= ~PSL_SE;
90 extern void booke_sstep(struct trapframe *); /* ugly */
91 booke_sstep(tf);
92 }
93 #endif
94
95 #ifdef __HAVE_RAS
96 /*
97 * Check to see if a RAS was interrupted and restart it if it was.
98 */
99 struct proc * const p = l->l_proc;
100 if (__predict_false(p->p_raslist != NULL)) {
101 void * const ras_pc = ras_lookup(p, (void *) tf->tf_srr0);
102 if (ras_pc != (void *) -1)
103 tf->tf_srr0 = (vaddr_t) ras_pc;
104 }
105 #endif
106 }
107