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 #ifdef __SPE__
44 #define	PPC_FEATURE_VECTOR	PPC_FEATURE_HAS_SPE
45 #else
46 #define	PPC_FEATURE_VECTOR	PPC_FEATURE_HAS_ALTIVEC
47 #endif
48 
49 int
50 cpu_ptrace(struct thread *td, int req, void *addr, int data)
51 {
52 	int error;
53 	struct pcb *pcb;
54 	struct vec vec;
55 	uint64_t vsr[32];
56 	uint64_t *vsr_dw1;
57 	int vsr_idx;
58 
59 	pcb = td->td_pcb;
60 
61 	bzero(&vec, sizeof(vec));
62 	bzero(vsr, sizeof(vsr));
63 
64 	error = EINVAL;
65 	switch (req) {
66 	case PT_GETVRREGS:
67 		if (!(cpu_features & PPC_FEATURE_VECTOR))
68 			break;
69 
70 		if (pcb->pcb_flags & PCB_VEC) {
71 			save_vec_nodrop(td);
72 			memcpy(&vec, &pcb->pcb_vec, sizeof(vec));
73 		}
74 		error = copyout(&vec, addr, sizeof(vec));
75 		break;
76 	case PT_SETVRREGS:
77 		if (!(cpu_features & PPC_FEATURE_VECTOR))
78 			break;
79 		error = copyin(addr, &vec, sizeof(vec));
80 		if (error == 0) {
81 			pcb->pcb_flags |= PCB_VEC;
82 			memcpy(&pcb->pcb_vec, &vec, sizeof(vec));
83 		}
84 		break;
85 	case PT_GETVSRREGS:
86 		if (!(cpu_features & PPC_FEATURE_HAS_VSX))
87 			break;
88 
89 		if (pcb->pcb_flags & PCB_VSX) {
90 			save_fpu_nodrop(td);
91 
92 			/*
93 			 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and
94 			 * VSR32-VSR63 overlap with VR0-VR31, so we only copy
95 			 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31.
96 			 */
97 			for (vsr_idx = 0; vsr_idx < nitems(vsr); vsr_idx++) {
98 				vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2];
99 				vsr[vsr_idx] = *vsr_dw1;
100 			}
101 		}
102 		error = copyout(&vsr, addr, sizeof(vsr));
103 		break;
104 	case PT_SETVSRREGS:
105 		if (!(cpu_features & PPC_FEATURE_HAS_VSX))
106 			break;
107 		error = copyin(addr, &vsr, sizeof(vsr));
108 		if (error == 0) {
109 			pcb->pcb_flags |= PCB_VSX;
110 
111 			/*
112 			 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and
113 			 * VSR32-VSR63 overlap with VR0-VR31, so we only copy
114 			 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31.
115 			 */
116 			for (vsr_idx = 0; vsr_idx < nitems(vsr); vsr_idx++) {
117 				vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2];
118 				*vsr_dw1 = vsr[vsr_idx];
119 			}
120 		}
121 		break;
122 
123 	default:
124 		break;
125 	}
126 
127 	return (error);
128 }
129