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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 21:20:57 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 21:20:57 +0900
commit0e51793e162ca432fc5f04178cf82b80a92c2659 (patch)
treecf7ffdb5064e2f7b6647a63e7323d1c4e99b7739 /arch/arm/include/asm/opcodes.h
parent5cad3598ea0cdb817681f74518d3213583a04f7a (diff)
parentb4874a3d298606c20118d1ead73235439bbc2823 (diff)
downloadlinux-0e51793e162ca432fc5f04178cf82b80a92c2659.tar.bz2
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King: "This is the first chunk of ARM updates for this merge window. Conflicts are expected in two files - asm/timex.h and mach-integrator/integrator_cp.c. Nothing particularly stands out more than anything else. Most of the growth is down to the opcodes stuff from Dave Martin, which is countered by Rob's patches to use more of the asm-generic headers on ARM." (A few more conflicts grew since then, but it all looked fairly trivial) * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits) ARM: 7548/1: include linux/sched.h in syscall.h ARM: 7541/1: Add ARM ERRATA 775420 workaround ARM: ensure vm_struct has its phys_addr member filled in ARM: 7540/1: kexec: Check segment memory addresses ARM: 7539/1: kexec: scan for dtb magic in segments ARM: 7538/1: delay: add registration mechanism for delay timer sources ARM: 7536/1: smp: Formalize an IPI for wakeup ARM: 7525/1: ptrace: use updated syscall number for syscall auditing ARM: 7524/1: support syscall tracing ARM: 7519/1: integrator: convert platform devices to Device Tree ARM: 7518/1: integrator: convert AMBA devices to device tree ARM: 7517/1: integrator: initial device tree support ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ ARM: 7515/1: integrator: check PL010 base address from resource ARM: 7514/1: integrator: call common init function from machine ARM: 7522/1: arch_timers: register a time/cycle counter ARM: 7523/1: arch_timers: enable the use of the virtual timer ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental ARM: 7520/1: Build dtb files in all target ARM: Fix build warning in arch/arm/mm/alignment.c ...
Diffstat (limited to 'arch/arm/include/asm/opcodes.h')
-rw-r--r--arch/arm/include/asm/opcodes.h181
1 files changed, 166 insertions, 15 deletions
diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h
index 19c48deda70f..74e211a6fb24 100644
--- a/arch/arm/include/asm/opcodes.h
+++ b/arch/arm/include/asm/opcodes.h
@@ -19,6 +19,33 @@ extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr);
/*
+ * 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
@@ -41,39 +68,163 @@ extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr);
* 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__
-#ifndef __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) swab32(x)
-#define __opcode_to_mem_thumb16(x) swab16(x)
-#define __opcode_to_mem_thumb32(x) swahb32(x)
-#else
-#define __opcode_to_mem_arm(x) ((u32)(x))
-#define __opcode_to_mem_thumb16(x) ((u16)(x))
-#define __opcode_to_mem_thumb32(x) swahw32(x)
+
+#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) ((u32)(x) >= 0xE8000000UL)
-#define __opcode_is_thumb16(x) ((u32)(x) < 0xE800UL)
+#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) ((u16)((x) >> 16))
-#define __opcode_thumb32_second(x) ((u16)(x))
-#define __opcode_thumb32_compose(first, second) \
- (((u32)(u16)(first) << 16) | (u32)(u16)(second))
+#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)) \
+)
-#endif /* __ASSEMBLY__ */
+/*
+ * 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 */