linux/arch/powerpc/kernel/jump_label.c
Jordan Niethe 94afd069d9 powerpc: Use a datatype for instructions
Currently unsigned ints are used to represent instructions on powerpc.
This has worked well as instructions have always been 4 byte words.

However, ISA v3.1 introduces some changes to instructions that mean
this scheme will no longer work as well. This change is Prefixed
Instructions. A prefixed instruction is made up of a word prefix
followed by a word suffix to make an 8 byte double word instruction.
No matter the endianness of the system the prefix always comes first.
Prefixed instructions are only planned for powerpc64.

Introduce a ppc_inst type to represent both prefixed and word
instructions on powerpc64 while keeping it possible to exclusively
have word instructions on powerpc32.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix compile error in emulate_spe()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com
2020-05-19 00:10:37 +10:00

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C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2010 Michael Ellerman, IBM Corp.
*/
#include <linux/kernel.h>
#include <linux/jump_label.h>
#include <asm/code-patching.h>
#include <asm/inst.h>
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct ppc_inst *addr = (struct ppc_inst *)(unsigned long)entry->code;
if (type == JUMP_LABEL_JMP)
patch_branch(addr, entry->target, 0);
else
patch_instruction(addr, ppc_inst(PPC_INST_NOP));
}