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Diffstat (limited to 'arch/powerpc/include/asm/sstep.h')
| -rw-r--r-- | arch/powerpc/include/asm/sstep.h | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/sstep.h b/arch/powerpc/include/asm/sstep.h new file mode 100644 index 000000000..50950deed --- /dev/null +++ b/arch/powerpc/include/asm/sstep.h @@ -0,0 +1,181 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM + */ +#include <asm/inst.h> + +struct pt_regs; + +/* + * We don't allow single-stepping an mtmsrd that would clear + * MSR_RI, since that would make the exception unrecoverable. + * Since we need to single-step to proceed from a breakpoint, + * we don't allow putting a breakpoint on an mtmsrd instruction. + * Similarly we don't allow breakpoints on rfid instructions. + * These macros tell us if an instruction is a mtmsrd or rfid. + * Note that these return true for both mtmsr/rfi (32-bit) + * and mtmsrd/rfid (64-bit). + */ +#define IS_MTMSRD(instr) ((ppc_inst_val(instr) & 0xfc0007be) == 0x7c000124) +#define IS_RFID(instr) ((ppc_inst_val(instr) & 0xfc0007be) == 0x4c000024) + +enum instruction_type { + COMPUTE, /* arith/logical/CR op, etc. */ + LOAD, /* load and store types need to be contiguous */ + LOAD_MULTI, + LOAD_FP, + LOAD_VMX, + LOAD_VSX, + STORE, + STORE_MULTI, + STORE_FP, + STORE_VMX, + STORE_VSX, + LARX, + STCX, + BRANCH, + MFSPR, + MTSPR, + CACHEOP, + BARRIER, + SYSCALL, + SYSCALL_VECTORED_0, + MFMSR, + MTMSR, + RFI, + INTERRUPT, + UNKNOWN +}; + +#define INSTR_TYPE_MASK 0x1f + +#define OP_IS_LOAD(type) ((LOAD <= (type) && (type) <= LOAD_VSX) || (type) == LARX) +#define OP_IS_STORE(type) ((STORE <= (type) && (type) <= STORE_VSX) || (type) == STCX) +#define OP_IS_LOAD_STORE(type) (LOAD <= (type) && (type) <= STCX) + +/* Compute flags, ORed in with type */ +#define SETREG 0x20 +#define SETCC 0x40 +#define SETXER 0x80 + +/* Branch flags, ORed in with type */ +#define SETLK 0x20 +#define BRTAKEN 0x40 +#define DECCTR 0x80 + +/* Load/store flags, ORed in with type */ +#define SIGNEXT 0x20 +#define UPDATE 0x40 /* matches bit in opcode 31 instructions */ +#define BYTEREV 0x80 +#define FPCONV 0x100 + +/* Barrier type field, ORed in with type */ +#define BARRIER_MASK 0xe0 +#define BARRIER_SYNC 0x00 +#define BARRIER_ISYNC 0x20 +#define BARRIER_EIEIO 0x40 +#define BARRIER_LWSYNC 0x60 +#define BARRIER_PTESYNC 0x80 + +/* Cacheop values, ORed in with type */ +#define CACHEOP_MASK 0x700 +#define DCBST 0 +#define DCBF 0x100 +#define DCBTST 0x200 +#define DCBT 0x300 +#define ICBI 0x400 +#define DCBZ 0x500 + +/* VSX flags values */ +#define VSX_FPCONV 1 /* do floating point SP/DP conversion */ +#define VSX_SPLAT 2 /* store loaded value into all elements */ +#define VSX_LDLEFT 4 /* load VSX register from left */ +#define VSX_CHECK_VEC 8 /* check MSR_VEC not MSR_VSX for reg >= 32 */ + +/* Prefixed flag, ORed in with type */ +#define PREFIXED 0x800 + +/* Size field in type word */ +#define SIZE(n) ((n) << 12) +#define GETSIZE(w) ((w) >> 12) + +#define GETTYPE(t) ((t) & INSTR_TYPE_MASK) +#define GETLENGTH(t) (((t) & PREFIXED) ? 8 : 4) + +#define MKOP(t, f, s) ((t) | (f) | SIZE(s)) + +/* Prefix instruction operands */ +#define GET_PREFIX_RA(i) (((i) >> 16) & 0x1f) +#define GET_PREFIX_R(i) ((i) & (1ul << 20)) + +extern s32 patch__exec_instr; + +struct instruction_op { + int type; + int reg; + unsigned long val; + /* For LOAD/STORE/LARX/STCX */ + unsigned long ea; + int update_reg; + /* For MFSPR */ + int spr; + u32 ccval; + u32 xerval; + u8 element_size; /* for VSX/VMX loads/stores */ + u8 vsx_flags; +}; + +union vsx_reg { + u8 b[16]; + u16 h[8]; + u32 w[4]; + unsigned long d[2]; + float fp[4]; + double dp[2]; + __vector128 v; +}; + +/* + * Decode an instruction, and return information about it in *op + * without changing *regs. + * + * Return value is 1 if the instruction can be emulated just by + * updating *regs with the information in *op, -1 if we need the + * GPRs but *regs doesn't contain the full register set, or 0 + * otherwise. + */ +extern int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, + ppc_inst_t instr); + +/* + * Emulate an instruction that can be executed just by updating + * fields in *regs. + */ +void emulate_update_regs(struct pt_regs *reg, struct instruction_op *op); + +/* + * Emulate instructions that cause a transfer of control, + * arithmetic/logical instructions, loads and stores, + * cache operations and barriers. + * + * Returns 1 if the instruction was emulated successfully, + * 0 if it could not be emulated, or -1 for an instruction that + * should not be emulated (rfid, mtmsrd clearing MSR_RI, etc.). + */ +int emulate_step(struct pt_regs *regs, ppc_inst_t instr); + +/* + * Emulate a load or store instruction by reading/writing the + * memory of the current process. FP/VMX/VSX registers are assumed + * to hold live values if the appropriate enable bit in regs->msr is + * set; otherwise this will use the saved values in the thread struct + * for user-mode accesses. + */ +extern int emulate_loadstore(struct pt_regs *regs, struct instruction_op *op); + +extern void emulate_vsx_load(struct instruction_op *op, union vsx_reg *reg, + const void *mem, bool cross_endian); +extern void emulate_vsx_store(struct instruction_op *op, + const union vsx_reg *reg, void *mem, + bool cross_endian); +extern int emulate_dcbz(unsigned long ea, struct pt_regs *regs); |