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authorLinus Torvalds <torvalds@linux-foundation.org>2012-01-06 18:15:25 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-06 18:15:25 -0800
commit770e1b035dcb6ec3f8ee69dda0815dd1e220a683 (patch)
treee6d36abfdb053fbc722aea8d7e946d6d1b93c7e1 /arch/arm/kernel/opcodes.c
parentd3d0b024348c040f0d6851e2e59fc961677d5169 (diff)
parent7b9dd47136c07ffd883aff6926c7b281e4c1eea4 (diff)
downloadlinux-770e1b035dcb6ec3f8ee69dda0815dd1e220a683.tar.bz2
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (207 commits) ARM: 7267/1: Remove BUILD_BUG_ON from asm/bug.h ARM: 7269/1: mach-sa1100: fix sched_clock breakage ARM: 7198/1: arm/imx6: add restart support for imx6q ARM: restart: remove the now empty arch_reset() ARM: restart: remove comments about adding code to arch_reset() ARM: restart: lpc32xx & u300: remove unnecessary printk ARM: restart: plat-samsung: remove plat/reset.h and s5p_reset_hook ARM: restart: w90x900: use new restart hook ARM: restart: Versatile Express: use new restart hook ARM: restart: versatile: use new restart hook ARM: restart: u300: use new restart hook ARM: restart: tegra: use new restart hook ARM: restart: spear: use new restart hook ARM: restart: shark: use new restart hook ARM: restart: sa1100: use new restart hook ARM: 7252/1: restart: S5PV210: use new restart hook ARM: 7251/1: restart: S5PC100: use new restart hook ARM: 7250/1: restart: S5P64X0: use new restart hook ARM: 7266/1: restart: S3C64XX: use new restart hook ARM: 7265/1: restart: S3C24XX: use new restart hook ... Fix up trivial conflict in arch/arm/mm/init.c due to removal of memblock_init() clashing with the movement of the sorting of the meminfo array.
Diffstat (limited to 'arch/arm/kernel/opcodes.c')
-rw-r--r--arch/arm/kernel/opcodes.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/arm/kernel/opcodes.c b/arch/arm/kernel/opcodes.c
new file mode 100644
index 000000000000..f8179c6a817f
--- /dev/null
+++ b/arch/arm/kernel/opcodes.c
@@ -0,0 +1,72 @@
+/*
+ * linux/arch/arm/kernel/opcodes.c
+ *
+ * A32 condition code lookup feature moved from nwfpe/fpopcode.c
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <asm/opcodes.h>
+
+#define ARM_OPCODE_CONDITION_UNCOND 0xf
+
+/*
+ * condition code lookup table
+ * index into the table is test code: EQ, NE, ... LT, GT, AL, NV
+ *
+ * bit position in short is condition code: NZCV
+ */
+static const unsigned short cc_map[16] = {
+ 0xF0F0, /* EQ == Z set */
+ 0x0F0F, /* NE */
+ 0xCCCC, /* CS == C set */
+ 0x3333, /* CC */
+ 0xFF00, /* MI == N set */
+ 0x00FF, /* PL */
+ 0xAAAA, /* VS == V set */
+ 0x5555, /* VC */
+ 0x0C0C, /* HI == C set && Z clear */
+ 0xF3F3, /* LS == C clear || Z set */
+ 0xAA55, /* GE == (N==V) */
+ 0x55AA, /* LT == (N!=V) */
+ 0x0A05, /* GT == (!Z && (N==V)) */
+ 0xF5FA, /* LE == (Z || (N!=V)) */
+ 0xFFFF, /* AL always */
+ 0 /* NV */
+};
+
+/*
+ * Returns:
+ * ARM_OPCODE_CONDTEST_FAIL - if condition fails
+ * ARM_OPCODE_CONDTEST_PASS - if condition passes (including AL)
+ * ARM_OPCODE_CONDTEST_UNCOND - if NV condition, or separate unconditional
+ * opcode space from v5 onwards
+ *
+ * Code that tests whether a conditional instruction would pass its condition
+ * check should check that return value == ARM_OPCODE_CONDTEST_PASS.
+ *
+ * Code that tests if a condition means that the instruction would be executed
+ * (regardless of conditional or unconditional) should instead check that the
+ * return value != ARM_OPCODE_CONDTEST_FAIL.
+ */
+asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr)
+{
+ u32 cc_bits = opcode >> 28;
+ u32 psr_cond = psr >> 28;
+ unsigned int ret;
+
+ if (cc_bits != ARM_OPCODE_CONDITION_UNCOND) {
+ if ((cc_map[cc_bits] >> (psr_cond)) & 1)
+ ret = ARM_OPCODE_CONDTEST_PASS;
+ else
+ ret = ARM_OPCODE_CONDTEST_FAIL;
+ } else {
+ ret = ARM_OPCODE_CONDTEST_UNCOND;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(arm_check_condition);