arch/arm/include/asm/opcodes.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *  arch/arm/include/asm/opcodes.h
  */

 #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 */
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* arch/arm/include/asm/opcodes.h
	*/

	#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 */