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// SPDX-License-Identifier: GPL-2.0
#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);
}
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