xref: /linux/arch/mips/kernel/perf_regs.c (revision ab52c59103002b49f2455371e4b9c56ba3ef1781)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * This file is subject to the terms and conditions of the GNU General Public
4  * License.  See the file "COPYING" in the main directory of this archive
5  * for more details.
6  *
7  * Some parts derived from x86 version of this file.
8  *
9  * Copyright (C) 2013 Cavium, Inc.
10  */
11 
12 #include <linux/perf_event.h>
13 
14 #include <asm/ptrace.h>
15 
16 #ifdef CONFIG_32BIT
17 u64 perf_reg_abi(struct task_struct *tsk)
18 {
19 	return PERF_SAMPLE_REGS_ABI_32;
20 }
21 #else /* Must be CONFIG_64BIT */
22 u64 perf_reg_abi(struct task_struct *tsk)
23 {
24 	if (test_tsk_thread_flag(tsk, TIF_32BIT_REGS))
25 		return PERF_SAMPLE_REGS_ABI_32;
26 	else
27 		return PERF_SAMPLE_REGS_ABI_64;
28 }
29 #endif /* CONFIG_32BIT */
30 
31 int perf_reg_validate(u64 mask)
32 {
33 	if (!mask)
34 		return -EINVAL;
35 	if (mask & ~((1ull << PERF_REG_MIPS_MAX) - 1))
36 		return -EINVAL;
37 	return 0;
38 }
39 
40 u64 perf_reg_value(struct pt_regs *regs, int idx)
41 {
42 	long v;
43 
44 	switch (idx) {
45 	case PERF_REG_MIPS_PC:
46 		v = regs->cp0_epc;
47 		break;
48 	case PERF_REG_MIPS_R1 ... PERF_REG_MIPS_R25:
49 		v = regs->regs[idx - PERF_REG_MIPS_R1 + 1];
50 		break;
51 	case PERF_REG_MIPS_R28 ... PERF_REG_MIPS_R31:
52 		v = regs->regs[idx - PERF_REG_MIPS_R28 + 28];
53 		break;
54 
55 	default:
56 		WARN_ON_ONCE(1);
57 		return 0;
58 	}
59 
60 	return (s64)v; /* Sign extend if 32-bit. */
61 }
62 
63 void perf_get_regs_user(struct perf_regs *regs_user,
64 			struct pt_regs *regs)
65 {
66 	regs_user->regs = task_pt_regs(current);
67 	regs_user->abi = perf_reg_abi(current);
68 }
69