diff options
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/module.h | 7 | ||||
| -rw-r--r-- | arch/arm/include/asm/runtime-patch.h | 208 |
2 files changed, 215 insertions, 0 deletions
diff --git a/arch/arm/include/asm/module.h b/arch/arm/include/asm/module.h index 0d3a28dbc8e..c4ebe522ca4 100644 --- a/arch/arm/include/asm/module.h +++ b/arch/arm/include/asm/module.h @@ -39,9 +39,16 @@ struct mod_arch_specific { #define MODULE_ARCH_VERMAGIC_ARMTHUMB "" #endif +#ifdef CONFIG_ARM_RUNTIME_PATCH +#define MODULE_ARCH_VERMAGIC_RT_PATCH "rt-patch " +#else +#define MODULE_ARCH_VERMAGIC_RT_PATCH "" +#endif + #define MODULE_ARCH_VERMAGIC \ MODULE_ARCH_VERMAGIC_ARMVSN \ MODULE_ARCH_VERMAGIC_ARMTHUMB \ + MODULE_ARCH_VERMAGIC_RT_PATCH \ MODULE_ARCH_VERMAGIC_P2V #endif /* _ASM_ARM_MODULE_H */ diff --git a/arch/arm/include/asm/runtime-patch.h b/arch/arm/include/asm/runtime-patch.h new file mode 100644 index 00000000000..366444d7eef --- /dev/null +++ b/arch/arm/include/asm/runtime-patch.h @@ -0,0 +1,208 @@ +/* + * arch/arm/include/asm/runtime-patch.h + * Note: this file should not be included by non-asm/.h files + * + * Copyright 2012 Texas Instruments, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_ARM_RUNTIME_PATCH_H +#define __ASM_ARM_RUNTIME_PATCH_H + +#include <linux/stringify.h> + +#ifndef __ASSEMBLY__ + +#ifdef CONFIG_ARM_RUNTIME_PATCH + +struct patch_info { + void *insn; + u16 type; + u8 insn_size; + u8 data_size; + u32 data[0]; +}; + +#define PATCH_IMM8 0x0001 +struct patch_info_imm8 { + u32 *imm; + u32 insn; +}; + +#define patch_next(p) ((void *)(p) + sizeof(*(p)) + (p)->data_size) +#define patch_data(p) ((void *)&(p)->data[0]) + +#define patch_stub(type, code, patch_data, ...) \ + __asm__("@ patch stub\n" \ + "1:\n" \ + code \ + "2:\n" \ + " .pushsection .runtime.patch.table, \"a\"\n" \ + "3:\n" \ + " .word 1b\n" \ + " .hword (" __stringify(type) ")\n" \ + " .byte (2b-1b)\n" \ + " .byte (5f-4f)\n" \ + "4:\n" \ + patch_data \ + " .align\n" \ + "5:\n" \ + " .popsection\n" \ + __VA_ARGS__) + +#define early_patch_stub(type, code, pad, patch_data, ...) \ + __asm__("@ patch stub\n" \ + "1:\n" \ + " b 6f\n" \ + " .fill " __stringify(pad) ", 1, 0\n" \ + "2:\n" \ + " .pushsection .runtime.patch.table, \"a\"\n" \ + "3:\n" \ + " .word 1b\n" \ + " .hword (" __stringify(type) ")\n" \ + " .byte (2b-1b)\n" \ + " .byte (5f-4f)\n" \ + "4:\n" \ + patch_data \ + " .align\n" \ + "5:\n" \ + " .popsection\n" \ + " .pushsection .runtime.patch.code, \"ax\"\n" \ + "6:\n" \ + code \ + " b 2b\n" \ + " .popsection\n" \ + __VA_ARGS__) + +/* constant used to force encoding */ +#define __IMM8 (0x81 << 24) + +/* + * patch_imm8() - init-time specialized binary operation (imm8 operand) + * This effectively does: to = from "insn" sym, + * where the value of sym is fixed at init-time, and is patched + * in as an immediate operand. This value must be + * representible as an 8-bit quantity with an optional + * rotation. + * + * The stub code produced by this variant is non-functional + * prior to patching. Use early_patch_imm8() if you need the + * code to be functional early on in the init sequence. + */ +#define patch_imm8(_insn, _to, _from, _sym, _ofs) \ + patch_stub( \ + /* type */ \ + PATCH_IMM8, \ + /* code */ \ + _insn " %[to], %[from], %[imm]\n", \ + /* patch_data */ \ + ".long " __stringify(_sym + _ofs) "\n" \ + _insn " %[to], %[from], %[imm]\n", \ + /* operands */ \ + : [to] "=r" (_to) \ + : [from] "r" (_from), \ + [imm] "I" (__IMM8), \ + "i" (&(_sym)) \ + : "cc") + +/* + * patch_imm8_mov() - same as patch_imm8(), but for mov/mvn instructions + */ +#define patch_imm8_mov(_insn, _to, _sym, _ofs) \ + patch_stub( \ + /* type */ \ + PATCH_IMM8, \ + /* code */ \ + _insn " %[to], %[imm]\n", \ + /* patch_data */ \ + ".long " __stringify(_sym + _ofs) "\n" \ + _insn " %[to], %[imm]\n", \ + /* operands */ \ + : [to] "=r" (_to) \ + : [imm] "I" (__IMM8), \ + "i" (&(_sym)) \ + : "cc") + +/* + * early_patch_imm8() - early functional variant of patch_imm8() above. The + * same restrictions on the constant apply here. This + * version emits workable (albeit inefficient) code at + * compile-time, and therefore functions even prior to + * patch application. + */ +#define early_patch_imm8(_insn, _to, _from, _sym, _ofs) \ +do { \ + unsigned long __tmp; \ + early_patch_stub( \ + /* type */ \ + PATCH_IMM8, \ + /* code */ \ + "ldr %[tmp], =" __stringify(_sym + _ofs) "\n"\ + "ldr %[tmp], [%[tmp]]\n" \ + _insn " %[to], %[from], %[tmp]\n", \ + /* pad */ \ + 0, \ + /* patch_data */ \ + ".long " __stringify(_sym + _ofs) "\n" \ + _insn " %[to], %[from], %[imm]\n", \ + /* operands */ \ + : [to] "=r" (_to), \ + [tmp] "=&r" (__tmp) \ + : [from] "r" (_from), \ + [imm] "I" (__IMM8), \ + "i" (&(_sym)) \ + : "cc"); \ +} while (0) + +#define early_patch_imm8_mov(_insn, _to, _sym, _ofs) \ +do { \ + unsigned long __tmp; \ + early_patch_stub( \ + /* type */ \ + PATCH_IMM8 \ + /* code */ \ + "ldr %[tmp], =" __stringify(_sym + _ofs) "\n"\ + "ldr %[tmp], [%[tmp]]\n" \ + _insn " %[to], %[tmp]\n", \ + /* pad */ \ + 0, \ + /* patch_data */ \ + ".long " __stringify(_sym + _ofs) "\n" \ + _insn " %[to], %[imm]\n", \ + /* operands */ \ + : [to] "=r" (_to), \ + [tmp] "=&r" (__tmp) \ + : [imm] "I" (__IMM8), \ + "i" (&(_sym)) \ + : "cc"); \ +} while (0) + +int runtime_patch(const void *table, unsigned size); +void runtime_patch_kernel(void); + +#else + +static inline int runtime_patch(const void *table, unsigned size) +{ + return 0; +} + +static inline void runtime_patch_kernel(void) +{ +} + +#endif /* CONFIG_ARM_RUNTIME_PATCH */ + +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_ARM_RUNTIME_PATCH_H */ |