/* * arch/arm/include/asm/opcodes.h * * 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 __ASM_ARM_OPCODES_H #define __ASM_ARM_OPCODES_H #ifndef __ASSEMBLY__ #include <linux/linkage.h> extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr); #endif #define ARM_OPCODE_CONDTEST_FAIL 0 #define ARM_OPCODE_CONDTEST_PASS 1 #define ARM_OPCODE_CONDTEST_UNCOND 2 /* * Assembler opcode byteswap helpers. * These are only intended for use by this header: don't use them directly, * because they will be suboptimal in most cases. */ #define ___asm_opcode_swab32(x) ( \ (((x) << 24) & 0xFF000000) \ | (((x) << 8) & 0x00FF0000) \ | (((x) >> 8) & 0x0000FF00) \ | (((x) >> 24) & 0x000000FF) \ ) #define ___asm_opcode_swab16(x) ( \ (((x) << 8) & 0xFF00) \ | (((x) >> 8) & 0x00FF) \ ) #define ___asm_opcode_swahb32(x) ( \ (((x) << 8) & 0xFF00FF00) \ | (((x) >> 8) & 0x00FF00FF) \ ) #define ___asm_opcode_swahw32(x) ( \ (((x) << 16) & 0xFFFF0000) \ | (((x) >> 16) & 0x0000FFFF) \ ) #define ___asm_opcode_identity32(x) ((x) & 0xFFFFFFFF) #define ___asm_opcode_identity16(x) ((x) & 0xFFFF) /* * Opcode byteswap helpers * * These macros help with converting instructions between a canonical integer * format and in-memory representation, in an endianness-agnostic manner. * * __mem_to_opcode_*() convert from in-memory representation to canonical form. * __opcode_to_mem_*() convert from canonical form to in-memory representation. * * * Canonical instruction representation: * * ARM: 0xKKLLMMNN * Thumb 16-bit: 0x0000KKLL, where KK < 0xE8 * Thumb 32-bit: 0xKKLLMMNN, where KK >= 0xE8 * * There is no way to distinguish an ARM instruction in canonical representation * from a Thumb instruction (just as these cannot be distinguished in memory). * Where this distinction is important, it needs to be tracked separately. * * Note that values in the range 0x0000E800..0xE7FFFFFF intentionally do not * represent any valid Thumb-2 instruction. For this range, * __opcode_is_thumb32() and __opcode_is_thumb16() will both be false. * * The ___asm variants are intended only for use by this header, in situations * involving inline assembler. For .S files, the normal __opcode_*() macros * should do the right thing. */ #ifdef __ASSEMBLY__ #define ___opcode_swab32(x) ___asm_opcode_swab32(x) #define ___opcode_swab16(x) ___asm_opcode_swab16(x) #define ___opcode_swahb32(x) ___asm_opcode_swahb32(x) #define ___opcode_swahw32(x) ___asm_opcode_swahw32(x) #define ___opcode_identity32(x) ___asm_opcode_identity32(x) #define ___opcode_identity16(x) ___asm_opcode_identity16(x) #else /* ! __ASSEMBLY__ */ #include <linux/types.h> #include <linux/swab.h> #define ___opcode_swab32(x) swab32(x) #define ___opcode_swab16(x) swab16(x) #define ___opcode_swahb32(x) swahb32(x) #define ___opcode_swahw32(x) swahw32(x) #define ___opcode_identity32(x) ((u32)(x)) #define ___opcode_identity16(x) ((u16)(x)) #endif /* ! __ASSEMBLY__ */ #ifdef CONFIG_CPU_ENDIAN_BE8 #define __opcode_to_mem_arm(x) ___opcode_swab32(x) #define __opcode_to_mem_thumb16(x) ___opcode_swab16(x) #define __opcode_to_mem_thumb32(x) ___opcode_swahb32(x) #define ___asm_opcode_to_mem_arm(x) ___asm_opcode_swab32(x) #define ___asm_opcode_to_mem_thumb16(x) ___asm_opcode_swab16(x) #define ___asm_opcode_to_mem_thumb32(x) ___asm_opcode_swahb32(x) #else /* ! CONFIG_CPU_ENDIAN_BE8 */ #define __opcode_to_mem_arm(x) ___opcode_identity32(x) #define __opcode_to_mem_thumb16(x) ___opcode_identity16(x) #define ___asm_opcode_to_mem_arm(x) ___asm_opcode_identity32(x) #define ___asm_opcode_to_mem_thumb16(x) ___asm_opcode_identity16(x) #ifndef CONFIG_CPU_ENDIAN_BE32 /* * On BE32 systems, using 32-bit accesses to store Thumb instructions will not * work in all cases, due to alignment constraints. For now, a correct * version is not provided for BE32. */ #define __opcode_to_mem_thumb32(x) ___opcode_swahw32(x) #define ___asm_opcode_to_mem_thumb32(x) ___asm_opcode_swahw32(x) #endif #endif /* ! CONFIG_CPU_ENDIAN_BE8 */ #define __mem_to_opcode_arm(x) __opcode_to_mem_arm(x) #define __mem_to_opcode_thumb16(x) __opcode_to_mem_thumb16(x) #ifndef CONFIG_CPU_ENDIAN_BE32 #define __mem_to_opcode_thumb32(x) __opcode_to_mem_thumb32(x) #endif /* Operations specific to Thumb opcodes */ /* Instruction size checks: */ #define __opcode_is_thumb32(x) ( \ ((x) & 0xF8000000) == 0xE8000000 \ || ((x) & 0xF0000000) == 0xF0000000 \ ) #define __opcode_is_thumb16(x) ( \ ((x) & 0xFFFF0000) == 0 \ && !(((x) & 0xF800) == 0xE800 || ((x) & 0xF000) == 0xF000) \ ) /* Operations to construct or split 32-bit Thumb instructions: */ #define __opcode_thumb32_first(x) (___opcode_identity16((x) >> 16)) #define __opcode_thumb32_second(x) (___opcode_identity16(x)) #define __opcode_thumb32_compose(first, second) ( \ (___opcode_identity32(___opcode_identity16(first)) << 16) \ | ___opcode_identity32(___opcode_identity16(second)) \ ) #define ___asm_opcode_thumb32_first(x) (___asm_opcode_identity16((x) >> 16)) #define ___asm_opcode_thumb32_second(x) (___asm_opcode_identity16(x)) #define ___asm_opcode_thumb32_compose(first, second) ( \ (___asm_opcode_identity32(___asm_opcode_identity16(first)) << 16) \ | ___asm_opcode_identity32(___asm_opcode_identity16(second)) \ ) /* * Opcode injection helpers * * In rare cases it is necessary to assemble an opcode which the * assembler does not support directly, or which would normally be * rejected because of the CFLAGS or AFLAGS used to build the affected * file. * * Before using these macros, consider carefully whether it is feasible * instead to change the build flags for your file, or whether it really * makes sense to support old assembler versions when building that * particular kernel feature. * * The macros defined here should only be used where there is no viable * alternative. * * * __inst_arm(x): emit the specified ARM opcode * __inst_thumb16(x): emit the specified 16-bit Thumb opcode * __inst_thumb32(x): emit the specified 32-bit Thumb opcode * * __inst_arm_thumb16(arm, thumb): emit either the specified arm or * 16-bit Thumb opcode, depending on whether an ARM or Thumb-2 * kernel is being built * * __inst_arm_thumb32(arm, thumb): emit either the specified arm or * 32-bit Thumb opcode, depending on whether an ARM or Thumb-2 * kernel is being built * * * Note that using these macros directly is poor practice. Instead, you * should use them to define human-readable wrapper macros to encode the * instructions that you care about. In code which might run on ARMv7 or * above, you can usually use the __inst_arm_thumb{16,32} macros to * specify the ARM and Thumb alternatives at the same time. This ensures * that the correct opcode gets emitted depending on the instruction set * used for the kernel build. * * Look at opcodes-virt.h for an example of how to use these macros. */ #include <linux/stringify.h> #define __inst_arm(x) ___inst_arm(___asm_opcode_to_mem_arm(x)) #define __inst_thumb32(x) ___inst_thumb32( \ ___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_first(x)), \ ___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_second(x)) \ ) #define __inst_thumb16(x) ___inst_thumb16(___asm_opcode_to_mem_thumb16(x)) #ifdef CONFIG_THUMB2_KERNEL #define __inst_arm_thumb16(arm_opcode, thumb_opcode) \ __inst_thumb16(thumb_opcode) #define __inst_arm_thumb32(arm_opcode, thumb_opcode) \ __inst_thumb32(thumb_opcode) #else #define __inst_arm_thumb16(arm_opcode, thumb_opcode) __inst_arm(arm_opcode) #define __inst_arm_thumb32(arm_opcode, thumb_opcode) __inst_arm(arm_opcode) #endif /* Helpers for the helpers. Don't use these directly. */ #ifdef __ASSEMBLY__ #define ___inst_arm(x) .long x #define ___inst_thumb16(x) .short x #define ___inst_thumb32(first, second) .short first, second #else #define ___inst_arm(x) ".long " __stringify(x) "\n\t" #define ___inst_thumb16(x) ".short " __stringify(x) "\n\t" #define ___inst_thumb32(first, second) \ ".short " __stringify(first) ", " __stringify(second) "\n\t" #endif #endif /* __ASM_ARM_OPCODES_H */