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authorVineet Gupta <vgupta@synopsys.com>2013-01-30 17:46:13 +0530
committerVineet Gupta <vgupta@synopsys.com>2013-02-15 23:16:04 +0530
commite65ab5a875d9e8ad8ff37529c2ae844699fefad1 (patch)
tree1aefe328299eaf1fbe48b27dd31c588b6e2b51b5 /arch/arc/include
parent44c8bb914028f34c622c30340fa21e186e4cf993 (diff)
ARC: disassembly (needed by kprobes/kgdb/unaligned-access-emul)
In-kernel disassembler Due Credits * Orig written by Rajeshwar Ranga * Consolidation/cleanups by Mischa Jonker Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Mischa Jonker <mjonker@synopsys.com>
Diffstat (limited to 'arch/arc/include')
-rw-r--r--arch/arc/include/asm/disasm.h116
1 files changed, 116 insertions, 0 deletions
diff --git a/arch/arc/include/asm/disasm.h b/arch/arc/include/asm/disasm.h
new file mode 100644
index 000000000000..f1cce3d059a1
--- /dev/null
+++ b/arch/arc/include/asm/disasm.h
@@ -0,0 +1,116 @@
+/*
+ * several functions that help interpret ARC instructions
+ * used for unaligned accesses, kprobes and kgdb
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __ARC_DISASM_H__
+#define __ARC_DISASM_H__
+
+enum {
+ op_Bcc = 0, op_BLcc = 1, op_LD = 2, op_ST = 3, op_MAJOR_4 = 4,
+ op_MAJOR_5 = 5, op_LD_ADD = 12, op_ADD_SUB_SHIFT = 13,
+ op_ADD_MOV_CMP = 14, op_S = 15, op_LD_S = 16, op_LDB_S = 17,
+ op_LDW_S = 18, op_LDWX_S = 19, op_ST_S = 20, op_STB_S = 21,
+ op_STW_S = 22, op_Su5 = 23, op_SP = 24, op_GP = 25,
+ op_Pcl = 26, op_MOV_S = 27, op_ADD_CMP = 28, op_BR_S = 29,
+ op_B_S = 30, op_BL_S = 31
+};
+
+enum flow {
+ noflow,
+ direct_jump,
+ direct_call,
+ indirect_jump,
+ indirect_call,
+ invalid_instr
+};
+
+#define IS_BIT(word, n) ((word) & (1<<n))
+#define BITS(word, s, e) (((word) >> (s)) & (~((-2) << ((e) - (s)))))
+
+#define MAJOR_OPCODE(word) (BITS((word), 27, 31))
+#define MINOR_OPCODE(word) (BITS((word), 16, 21))
+#define FIELD_A(word) (BITS((word), 0, 5))
+#define FIELD_B(word) ((BITS((word), 12, 14)<<3) | \
+ (BITS((word), 24, 26)))
+#define FIELD_C(word) (BITS((word), 6, 11))
+#define FIELD_u6(word) FIELDC(word)
+#define FIELD_s12(word) sign_extend(((BITS((word), 0, 5) << 6) | \
+ BITS((word), 6, 11)), 12)
+
+/* note that for BL/BRcc these two macro's need another AND statement to mask
+ * out bit 1 (make the result a multiple of 4) */
+#define FIELD_s9(word) sign_extend(((BITS(word, 15, 15) << 8) | \
+ BITS(word, 16, 23)), 9)
+#define FIELD_s21(word) sign_extend(((BITS(word, 6, 15) << 11) | \
+ (BITS(word, 17, 26) << 1)), 12)
+#define FIELD_s25(word) sign_extend(((BITS(word, 0, 3) << 21) | \
+ (BITS(word, 6, 15) << 11) | \
+ (BITS(word, 17, 26) << 1)), 12)
+
+/* note: these operate on 16 bits! */
+#define FIELD_S_A(word) ((BITS((word), 2, 2)<<3) | BITS((word), 0, 2))
+#define FIELD_S_B(word) ((BITS((word), 10, 10)<<3) | \
+ BITS((word), 8, 10))
+#define FIELD_S_C(word) ((BITS((word), 7, 7)<<3) | BITS((word), 5, 7))
+#define FIELD_S_H(word) ((BITS((word), 0, 2)<<3) | BITS((word), 5, 8))
+#define FIELD_S_u5(word) (BITS((word), 0, 4))
+#define FIELD_S_u6(word) (BITS((word), 0, 4) << 1)
+#define FIELD_S_u7(word) (BITS((word), 0, 4) << 2)
+#define FIELD_S_u10(word) (BITS((word), 0, 7) << 2)
+#define FIELD_S_s7(word) sign_extend(BITS((word), 0, 5) << 1, 9)
+#define FIELD_S_s8(word) sign_extend(BITS((word), 0, 7) << 1, 9)
+#define FIELD_S_s9(word) sign_extend(BITS((word), 0, 8), 9)
+#define FIELD_S_s10(word) sign_extend(BITS((word), 0, 8) << 1, 10)
+#define FIELD_S_s11(word) sign_extend(BITS((word), 0, 8) << 2, 11)
+#define FIELD_S_s13(word) sign_extend(BITS((word), 0, 10) << 2, 13)
+
+#define STATUS32_L 0x00000100
+#define REG_LIMM 62
+
+struct disasm_state {
+ /* generic info */
+ unsigned long words[2];
+ int instr_len;
+ int major_opcode;
+ /* info for branch/jump */
+ int is_branch;
+ int target;
+ int delay_slot;
+ enum flow flow;
+ /* info for load/store */
+ int src1, src2, src3, dest, wb_reg;
+ int zz, aa, x, pref, di;
+ int fault, write;
+};
+
+static inline int sign_extend(int value, int bits)
+{
+ if (IS_BIT(value, (bits - 1)))
+ value |= (0xffffffff << bits);
+
+ return value;
+}
+
+static inline int is_short_instr(unsigned long addr)
+{
+ uint16_t word = *((uint16_t *)addr);
+ int opcode = (word >> 11) & 0x1F;
+ return (opcode >= 0x0B);
+}
+
+void disasm_instr(unsigned long addr, struct disasm_state *state,
+ int userspace, struct pt_regs *regs, struct callee_regs *cregs);
+int disasm_next_pc(unsigned long pc, struct pt_regs *regs, struct callee_regs
+ *cregs, unsigned long *fall_thru, unsigned long *target);
+long get_reg(int reg, struct pt_regs *regs, struct callee_regs *cregs);
+void set_reg(int reg, long val, struct pt_regs *regs,
+ struct callee_regs *cregs);
+
+#endif /* __ARC_DISASM_H__ */