1 /*-
2  * Copyright (c) 2014 Justin Hibbits
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/malloc.h>
34 #include <sys/proc.h>
35 #include <sys/ptrace.h>
36 #include <sys/sysent.h>
37 #include <machine/altivec.h>
38 #include <machine/fpu.h>
39 #include <machine/cpu.h>
40 #include <machine/md_var.h>
41 #include <machine/pcb.h>
42 
43 int
44 cpu_ptrace(struct thread *td, int req, void *addr, int data)
45 {
46 	int error;
47 	struct pcb *pcb;
48 	struct vec vec;
49 	uint64_t vsr[32];
50 	uint64_t *vsr_dw1;
51 	int vsr_idx;
52 
53 	pcb = td->td_pcb;
54 
55 	bzero(&vec, sizeof(vec));
56 	bzero(vsr, sizeof(vsr));
57 
58 	error = EINVAL;
59 	switch (req) {
60 	case PT_GETVRREGS:
61 		if (!(cpu_features & PPC_FEATURE_HAS_ALTIVEC))
62 			break;
63 
64 		if (pcb->pcb_flags & PCB_VEC) {
65 			save_vec_nodrop(td);
66 			memcpy(&vec, &pcb->pcb_vec, sizeof(vec));
67 		}
68 		error = copyout(&vec, addr, sizeof(vec));
69 		break;
70 	case PT_SETVRREGS:
71 		if (!(cpu_features & PPC_FEATURE_HAS_ALTIVEC))
72 			break;
73 		error = copyin(addr, &vec, sizeof(vec));
74 		if (error == 0) {
75 			pcb->pcb_flags |= PCB_VEC;
76 			memcpy(&pcb->pcb_vec, &vec, sizeof(vec));
77 		}
78 		break;
79 	case PT_GETVSRREGS:
80 		if (!(cpu_features & PPC_FEATURE_HAS_VSX))
81 			break;
82 
83 		if (pcb->pcb_flags & PCB_VSX) {
84 			save_fpu_nodrop(td);
85 
86 			/*
87 			 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and
88 			 * VSR32-VSR63 overlap with VR0-VR31, so we only copy
89 			 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31.
90 			 */
91 			for (vsr_idx = 0; vsr_idx < nitems(vsr); vsr_idx++) {
92 				vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2];
93 				vsr[vsr_idx] = *vsr_dw1;
94 			}
95 		}
96 		error = copyout(&vsr, addr, sizeof(vsr));
97 		break;
98 	case PT_SETVSRREGS:
99 		if (!(cpu_features & PPC_FEATURE_HAS_VSX))
100 			break;
101 		error = copyin(addr, &vsr, sizeof(vsr));
102 		if (error == 0) {
103 			pcb->pcb_flags |= PCB_VSX;
104 
105 			/*
106 			 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and
107 			 * VSR32-VSR63 overlap with VR0-VR31, so we only copy
108 			 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31.
109 			 */
110 			for (vsr_idx = 0; vsr_idx < nitems(vsr); vsr_idx++) {
111 				vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2];
112 				*vsr_dw1 = vsr[vsr_idx];
113 			}
114 		}
115 		break;
116 
117 	default:
118 		break;
119 	}
120 
121 	return (error);
122 }
123