xref: /netbsd-src/sys/arch/arm/arm/process_machdep.c (revision 496e2b659f2819a14d8716cb7e5992ffb8b0455f)
1 /*	$NetBSD: process_machdep.c,v 1.35 2021/02/01 19:31:34 skrll Exp $	*/
2 
3 /*
4  * Copyright (c) 1993 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Jan-Simon Pendry.
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. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * From:
35  *	Id: procfs_i386.c,v 4.1 1993/12/17 10:47:45 jsp Rel
36  */
37 
38 /*
39  * Copyright (c) 1995 Frank Lancaster.  All rights reserved.
40  * Copyright (c) 1995 Tools GmbH.  All rights reserved.
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *      This product includes software developed by TooLs GmbH.
54  * 4. The name of TooLs GmbH may not be used to endorse or promote products
55  *    derived from this software without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
58  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
62  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
63  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
64  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
65  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
66  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 /*
70  * Copyright (c) 1995 Charles M. Hannum.  All rights reserved.
71  * Copyright (c) 1993 Jan-Simon Pendry
72  * All rights reserved.
73  *
74  * This code is derived from software contributed to Berkeley by
75  * Jan-Simon Pendry.
76  *
77  * Redistribution and use in source and binary forms, with or without
78  * modification, are permitted provided that the following conditions
79  * are met:
80  * 1. Redistributions of source code must retain the above copyright
81  *    notice, this list of conditions and the following disclaimer.
82  * 2. Redistributions in binary form must reproduce the above copyright
83  *    notice, this list of conditions and the following disclaimer in the
84  *    documentation and/or other materials provided with the distribution.
85  * 3. All advertising materials mentioning features or use of this software
86  *    must display the following acknowledgement:
87  *	This product includes software developed by the University of
88  *	California, Berkeley and its contributors.
89  * 4. Neither the name of the University nor the names of its contributors
90  *    may be used to endorse or promote products derived from this software
91  *    without specific prior written permission.
92  *
93  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
94  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
95  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
96  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
97  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
98  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
99  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
101  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
102  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
103  * SUCH DAMAGE.
104  *
105  * From:
106  *	Id: procfs_i386.c,v 4.1 1993/12/17 10:47:45 jsp Rel
107  */
108 
109 /*
110  * This file may seem a bit stylized, but that so that it's easier to port.
111  * Functions to be implemented here are:
112  *
113  * process_read_regs(proc, regs)
114  *	Get the current user-visible register set from the process
115  *	and copy it into the regs structure (<machine/reg.h>).
116  *	The process is stopped at the time read_regs is called.
117  *
118  * process_write_regs(proc, regs)
119  *	Update the current register set from the passed in regs
120  *	structure.  Take care to avoid clobbering special CPU
121  *	registers or privileged bits in the PSL.
122  *	The process is stopped at the time write_regs is called.
123  *
124  * process_sstep(proc, sstep)
125  *	Arrange for the process to trap or not trap depending on sstep
126  *	after executing a single instruction.
127  *
128  * process_set_pc(proc)
129  *	Set the process's program counter.
130  */
131 
132 #ifdef _KERNEL_OPT
133 #include "opt_armfpe.h"
134 #endif
135 
136 #include <sys/param.h>
137 
138 __KERNEL_RCSID(0, "$NetBSD: process_machdep.c,v 1.35 2021/02/01 19:31:34 skrll Exp $");
139 
140 #include <sys/proc.h>
141 #include <sys/ptrace.h>
142 #include <sys/systm.h>
143 
144 #include <arm/armreg.h>
145 #include <arm/vfpreg.h>
146 #include <arm/locore.h>
147 
148 #include <machine/pcb.h>
149 #include <machine/reg.h>
150 
151 int
process_read_regs(struct lwp * l,struct reg * regs)152 process_read_regs(struct lwp *l, struct reg *regs)
153 {
154 	struct trapframe * const tf = lwp_trapframe(l);
155 
156 	KASSERT(tf != NULL);
157 	memcpy((void *)regs->r, (void *)&tf->tf_r0, sizeof(regs->r));
158 	regs->r_sp = tf->tf_usr_sp;
159 	regs->r_lr = tf->tf_usr_lr;
160 	regs->r_pc = tf->tf_pc;
161 	regs->r_cpsr = tf->tf_spsr;
162 
163 	KASSERT(VALID_PSR(tf->tf_spsr));
164 
165 #ifdef THUMB_CODE
166 	if (tf->tf_spsr & PSR_T_bit)
167 		regs->r_pc |= 1;
168 #endif
169 
170 	return 0;
171 }
172 
173 int
process_read_fpregs(struct lwp * l,struct fpreg * regs,size_t * sz)174 process_read_fpregs(struct lwp *l, struct fpreg *regs, size_t *sz)
175 {
176 #ifdef FPU_VFP
177 	if (curcpu()->ci_vfp_id == 0) {
178 		memset(regs, 0, sizeof(*regs));
179 		return 0;
180 	}
181 	const struct pcb * const pcb = lwp_getpcb(l);
182 	vfp_savecontext(l);
183 	regs->fpr_vfp = pcb->pcb_vfp;
184 	regs->fpr_vfp.vfp_fpexc &= ~VFP_FPEXC_EN;
185 #endif
186 	return 0;
187 }
188 
189 int
process_write_regs(struct lwp * l,const struct reg * regs)190 process_write_regs(struct lwp *l, const struct reg *regs)
191 {
192 	struct trapframe * const tf = lwp_trapframe(l);
193 
194 	KASSERT(tf != NULL);
195 	memcpy(&tf->tf_r0, regs->r, sizeof(regs->r));
196 	tf->tf_usr_sp = regs->r_sp;
197 	tf->tf_usr_lr = regs->r_lr;
198 	tf->tf_pc = regs->r_pc;
199 	tf->tf_spsr &=  ~(PSR_FLAGS | PSR_T_bit);
200 	tf->tf_spsr |= regs->r_cpsr & PSR_FLAGS;
201 #ifdef THUMB_CODE
202 	if ((regs->r_pc & 1) || (regs->r_cpsr & PSR_T_bit))
203 		tf->tf_spsr |= PSR_T_bit;
204 #endif
205 	KASSERT(VALID_PSR(tf->tf_spsr));
206 
207 	return 0;
208 }
209 
210 int
process_write_fpregs(struct lwp * l,const struct fpreg * regs,size_t sz)211 process_write_fpregs(struct lwp *l, const struct fpreg *regs, size_t sz)
212 {
213 #ifdef FPU_VFP
214 	if (curcpu()->ci_vfp_id == 0) {
215 		return EINVAL;
216 	}
217 	struct pcb * const pcb = lwp_getpcb(l);
218 	vfp_discardcontext(l, true);
219 	pcb->pcb_vfp = regs->fpr_vfp;
220 	pcb->pcb_vfp.vfp_fpexc &= ~VFP_FPEXC_EN;
221 #endif
222 	return 0;
223 }
224 
225 int
process_set_pc(struct lwp * l,void * addr)226 process_set_pc(struct lwp *l, void *addr)
227 {
228 	struct trapframe * const tf = lwp_trapframe(l);
229 
230 	KASSERT(tf != NULL);
231 	tf->tf_pc = (int)addr;
232 #ifdef THUMB_CODE
233 	if (((int)addr) & 1)
234 		tf->tf_spsr |= PSR_T_bit;
235 	else
236 		tf->tf_spsr &= ~PSR_T_bit;
237 #endif
238 
239 	return 0;
240 }
241