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-rw-r--r--arch/powerpc/include/asm/sstep.h181
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/sstep.h b/arch/powerpc/include/asm/sstep.h
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+++ b/arch/powerpc/include/asm/sstep.h
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+/* 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);