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Diffstat (limited to 'arch/ppc64/lib/sstep.c')
-rw-r--r--arch/ppc64/lib/sstep.c141
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;
-}