diff options
Diffstat (limited to 'arch/ppc64/lib/sstep.c')
| -rw-r--r-- | arch/ppc64/lib/sstep.c | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/arch/ppc64/lib/sstep.c b/arch/ppc64/lib/sstep.c deleted file mode 100644 index e79123d1485..00000000000 --- a/arch/ppc64/lib/sstep.c +++ /dev/null @@ -1,141 +0,0 @@ -/* - * Single-step support. - * - * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ -#include <linux/kernel.h> -#include <linux/ptrace.h> -#include <asm/sstep.h> -#include <asm/processor.h> - -extern char system_call_common[]; - -/* Bits in SRR1 that are copied from MSR */ -#define MSR_MASK 0xffffffff87c0ffff - -/* - * Determine whether a conditional branch instruction would branch. - */ -static int branch_taken(unsigned int instr, struct pt_regs *regs) -{ - unsigned int bo = (instr >> 21) & 0x1f; - unsigned int bi; - - if ((bo & 4) == 0) { - /* decrement counter */ - --regs->ctr; - if (((bo >> 1) & 1) ^ (regs->ctr == 0)) - return 0; - } - if ((bo & 0x10) == 0) { - /* check bit from CR */ - bi = (instr >> 16) & 0x1f; - if (((regs->ccr >> (31 - bi)) & 1) != ((bo >> 3) & 1)) - return 0; - } - return 1; -} - -/* - * Emulate instructions that cause a transfer of control. - * Returns 1 if the step was emulated, 0 if not, - * or -1 if the instruction is one that should not be stepped, - * such as an rfid, or a mtmsrd that would clear MSR_RI. - */ -int emulate_step(struct pt_regs *regs, unsigned int instr) -{ - unsigned int opcode, rd; - unsigned long int imm; - - opcode = instr >> 26; - switch (opcode) { - case 16: /* bc */ - imm = (signed short)(instr & 0xfffc); - if ((instr & 2) == 0) - imm += regs->nip; - regs->nip += 4; - if ((regs->msr & MSR_SF) == 0) - regs->nip &= 0xffffffffUL; - if (instr & 1) - regs->link = regs->nip; - if (branch_taken(instr, regs)) - regs->nip = imm; - return 1; - case 17: /* sc */ - /* - * N.B. this uses knowledge about how the syscall - * entry code works. If that is changed, this will - * need to be changed also. - */ - regs->gpr[9] = regs->gpr[13]; - regs->gpr[11] = regs->nip + 4; - regs->gpr[12] = regs->msr & MSR_MASK; - regs->gpr[13] = (unsigned long) get_paca(); - regs->nip = (unsigned long) &system_call_common; - regs->msr = MSR_KERNEL; - return 1; - case 18: /* b */ - imm = instr & 0x03fffffc; - if (imm & 0x02000000) - imm -= 0x04000000; - if ((instr & 2) == 0) - imm += regs->nip; - if (instr & 1) { - regs->link = regs->nip + 4; - if ((regs->msr & MSR_SF) == 0) - regs->link &= 0xffffffffUL; - } - if ((regs->msr & MSR_SF) == 0) - imm &= 0xffffffffUL; - regs->nip = imm; - return 1; - case 19: - switch (instr & 0x7fe) { - case 0x20: /* bclr */ - case 0x420: /* bcctr */ - imm = (instr & 0x400)? regs->ctr: regs->link; - regs->nip += 4; - if ((regs->msr & MSR_SF) == 0) { - regs->nip &= 0xffffffffUL; - imm &= 0xffffffffUL; - } - if (instr & 1) - regs->link = regs->nip; - if (branch_taken(instr, regs)) - regs->nip = imm; - return 1; - case 0x24: /* rfid, scary */ - return -1; - } - case 31: - rd = (instr >> 21) & 0x1f; - switch (instr & 0x7fe) { - case 0xa6: /* mfmsr */ - regs->gpr[rd] = regs->msr & MSR_MASK; - regs->nip += 4; - if ((regs->msr & MSR_SF) == 0) - regs->nip &= 0xffffffffUL; - return 1; - case 0x164: /* mtmsrd */ - /* only MSR_EE and MSR_RI get changed if bit 15 set */ - /* mtmsrd doesn't change MSR_HV and MSR_ME */ - imm = (instr & 0x10000)? 0x8002: 0xefffffffffffefffUL; - imm = (regs->msr & MSR_MASK & ~imm) - | (regs->gpr[rd] & imm); - if ((imm & MSR_RI) == 0) - /* can't step mtmsrd that would clear MSR_RI */ - return -1; - regs->msr = imm; - regs->nip += 4; - if ((imm & MSR_SF) == 0) - regs->nip &= 0xffffffffUL; - return 1; - } - } - return 0; -} |