diff options
author | Zi Shen Lim <zlim.lnx@gmail.com> | 2014-08-27 04:15:17 (GMT) |
---|---|---|
committer | Will Deacon <will.deacon@arm.com> | 2014-09-08 13:39:19 (GMT) |
commit | 617d2fbc45233bed182accd3507d0df4d213492c (patch) | |
tree | 291332444d75fb00827784f4f0375bb963b52e7d /arch/arm64 | |
parent | a4ceab1adbe960c781e9e2f659d7f7840eefd786 (diff) | |
download | linux-617d2fbc45233bed182accd3507d0df4d213492c.tar.xz |
arm64: introduce aarch64_insn_gen_comp_branch_imm()
Introduce function to generate compare & branch (immediate)
instructions.
Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/include/asm/insn.h | 57 | ||||
-rw-r--r-- | arch/arm64/kernel/insn.c | 88 |
2 files changed, 140 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h index dc1f73b..a98c495 100644 --- a/arch/arm64/include/asm/insn.h +++ b/arch/arm64/include/asm/insn.h @@ -2,6 +2,8 @@ * Copyright (C) 2013 Huawei Ltd. * Author: Jiang Liu <liuj97@gmail.com> * + * Copyright (C) 2014 Zi Shen Lim <zlim.lnx@gmail.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. @@ -67,9 +69,58 @@ enum aarch64_insn_imm_type { AARCH64_INSN_IMM_MAX }; +enum aarch64_insn_register_type { + AARCH64_INSN_REGTYPE_RT, +}; + +enum aarch64_insn_register { + AARCH64_INSN_REG_0 = 0, + AARCH64_INSN_REG_1 = 1, + AARCH64_INSN_REG_2 = 2, + AARCH64_INSN_REG_3 = 3, + AARCH64_INSN_REG_4 = 4, + AARCH64_INSN_REG_5 = 5, + AARCH64_INSN_REG_6 = 6, + AARCH64_INSN_REG_7 = 7, + AARCH64_INSN_REG_8 = 8, + AARCH64_INSN_REG_9 = 9, + AARCH64_INSN_REG_10 = 10, + AARCH64_INSN_REG_11 = 11, + AARCH64_INSN_REG_12 = 12, + AARCH64_INSN_REG_13 = 13, + AARCH64_INSN_REG_14 = 14, + AARCH64_INSN_REG_15 = 15, + AARCH64_INSN_REG_16 = 16, + AARCH64_INSN_REG_17 = 17, + AARCH64_INSN_REG_18 = 18, + AARCH64_INSN_REG_19 = 19, + AARCH64_INSN_REG_20 = 20, + AARCH64_INSN_REG_21 = 21, + AARCH64_INSN_REG_22 = 22, + AARCH64_INSN_REG_23 = 23, + AARCH64_INSN_REG_24 = 24, + AARCH64_INSN_REG_25 = 25, + AARCH64_INSN_REG_26 = 26, + AARCH64_INSN_REG_27 = 27, + AARCH64_INSN_REG_28 = 28, + AARCH64_INSN_REG_29 = 29, + AARCH64_INSN_REG_FP = 29, /* Frame pointer */ + AARCH64_INSN_REG_30 = 30, + AARCH64_INSN_REG_LR = 30, /* Link register */ + AARCH64_INSN_REG_ZR = 31, /* Zero: as source register */ + AARCH64_INSN_REG_SP = 31 /* Stack pointer: as load/store base reg */ +}; + +enum aarch64_insn_variant { + AARCH64_INSN_VARIANT_32BIT, + AARCH64_INSN_VARIANT_64BIT +}; + enum aarch64_insn_branch_type { AARCH64_INSN_BRANCH_NOLINK, AARCH64_INSN_BRANCH_LINK, + AARCH64_INSN_BRANCH_COMP_ZERO, + AARCH64_INSN_BRANCH_COMP_NONZERO, }; #define __AARCH64_INSN_FUNCS(abbr, mask, val) \ @@ -80,6 +131,8 @@ static __always_inline u32 aarch64_insn_get_##abbr##_value(void) \ __AARCH64_INSN_FUNCS(b, 0xFC000000, 0x14000000) __AARCH64_INSN_FUNCS(bl, 0xFC000000, 0x94000000) +__AARCH64_INSN_FUNCS(cbz, 0xFE000000, 0x34000000) +__AARCH64_INSN_FUNCS(cbnz, 0xFE000000, 0x35000000) __AARCH64_INSN_FUNCS(svc, 0xFFE0001F, 0xD4000001) __AARCH64_INSN_FUNCS(hvc, 0xFFE0001F, 0xD4000002) __AARCH64_INSN_FUNCS(smc, 0xFFE0001F, 0xD4000003) @@ -97,6 +150,10 @@ u32 aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, u32 insn, u64 imm); u32 aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, enum aarch64_insn_branch_type type); +u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_register reg, + enum aarch64_insn_variant variant, + enum aarch64_insn_branch_type type); u32 aarch64_insn_gen_hint(enum aarch64_insn_hint_op op); u32 aarch64_insn_gen_nop(void); diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index 92f3683..d9f7827 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -2,6 +2,8 @@ * Copyright (C) 2013 Huawei Ltd. * Author: Jiang Liu <liuj97@gmail.com> * + * Copyright (C) 2014 Zi Shen Lim <zlim.lnx@gmail.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. @@ -23,6 +25,8 @@ #include <asm/cacheflush.h> #include <asm/insn.h> +#define AARCH64_INSN_SF_BIT BIT(31) + static int aarch64_insn_encoding_class[] = { AARCH64_INSN_CLS_UNKNOWN, AARCH64_INSN_CLS_UNKNOWN, @@ -264,10 +268,36 @@ u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, return insn; } -u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, - enum aarch64_insn_branch_type type) +static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type, + u32 insn, + enum aarch64_insn_register reg) +{ + int shift; + + if (reg < AARCH64_INSN_REG_0 || reg > AARCH64_INSN_REG_SP) { + pr_err("%s: unknown register encoding %d\n", __func__, reg); + return 0; + } + + switch (type) { + case AARCH64_INSN_REGTYPE_RT: + shift = 0; + break; + default: + pr_err("%s: unknown register type encoding %d\n", __func__, + type); + return 0; + } + + insn &= ~(GENMASK(4, 0) << shift); + insn |= reg << shift; + + return insn; +} + +static inline long branch_imm_common(unsigned long pc, unsigned long addr, + long range) { - u32 insn; long offset; /* @@ -276,13 +306,24 @@ u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, */ BUG_ON((pc & 0x3) || (addr & 0x3)); + offset = ((long)addr - (long)pc); + BUG_ON(offset < -range || offset >= range); + + return offset; +} + +u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_branch_type type) +{ + u32 insn; + long offset; + /* * B/BL support [-128M, 128M) offset * ARM64 virtual address arrangement guarantees all kernel and module * texts are within +/-128M. */ - offset = ((long)addr - (long)pc); - BUG_ON(offset < -SZ_128M || offset >= SZ_128M); + offset = branch_imm_common(pc, addr, SZ_128M); if (type == AARCH64_INSN_BRANCH_LINK) insn = aarch64_insn_get_bl_value(); @@ -293,6 +334,43 @@ u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, offset >> 2); } +u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_register reg, + enum aarch64_insn_variant variant, + enum aarch64_insn_branch_type type) +{ + u32 insn; + long offset; + + offset = branch_imm_common(pc, addr, SZ_1M); + + switch (type) { + case AARCH64_INSN_BRANCH_COMP_ZERO: + insn = aarch64_insn_get_cbz_value(); + break; + case AARCH64_INSN_BRANCH_COMP_NONZERO: + insn = aarch64_insn_get_cbnz_value(); + break; + default: + BUG_ON(1); + } + + switch (variant) { + case AARCH64_INSN_VARIANT_32BIT: + break; + case AARCH64_INSN_VARIANT_64BIT: + insn |= AARCH64_INSN_SF_BIT; + break; + default: + BUG_ON(1); + } + + insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg); + + return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn, + offset >> 2); +} + u32 __kprobes aarch64_insn_gen_hint(enum aarch64_insn_hint_op op) { return aarch64_insn_get_hint_value() | op; |