arch/mips/kernel/perf_regs.c

   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 }