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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /arch/arm/kernel/insn.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/arm/kernel/insn.c')
-rw-r--r--arch/arm/kernel/insn.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/arm/kernel/insn.c b/arch/arm/kernel/insn.c
new file mode 100644
index 00000000000..b760340b701
--- /dev/null
+++ b/arch/arm/kernel/insn.c
@@ -0,0 +1,62 @@
+#include <linux/bug.h>
+#include <linux/kernel.h>
+#include <asm/opcodes.h>
+
+static unsigned long
+__arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
+{
+ unsigned long s, j1, j2, i1, i2, imm10, imm11;
+ unsigned long first, second;
+ long offset;
+
+ offset = (long)addr - (long)(pc + 4);
+ if (offset < -16777216 || offset > 16777214) {
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ s = (offset >> 24) & 0x1;
+ i1 = (offset >> 23) & 0x1;
+ i2 = (offset >> 22) & 0x1;
+ imm10 = (offset >> 12) & 0x3ff;
+ imm11 = (offset >> 1) & 0x7ff;
+
+ j1 = (!i1) ^ s;
+ j2 = (!i2) ^ s;
+
+ first = 0xf000 | (s << 10) | imm10;
+ second = 0x9000 | (j1 << 13) | (j2 << 11) | imm11;
+ if (link)
+ second |= 1 << 14;
+
+ return __opcode_thumb32_compose(first, second);
+}
+
+static unsigned long
+__arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
+{
+ unsigned long opcode = 0xea000000;
+ long offset;
+
+ if (link)
+ opcode |= 1 << 24;
+
+ offset = (long)addr - (long)(pc + 8);
+ if (unlikely(offset < -33554432 || offset > 33554428)) {
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ offset = (offset >> 2) & 0x00ffffff;
+
+ return opcode | offset;
+}
+
+unsigned long
+__arm_gen_branch(unsigned long pc, unsigned long addr, bool link)
+{
+ if (IS_ENABLED(CONFIG_THUMB2_KERNEL))
+ return __arm_gen_branch_thumb2(pc, addr, link);
+ else
+ return __arm_gen_branch_arm(pc, addr, link);
+}