1
linux/arch/arm/kernel/iwmmxt.h
Jian Cai 3c9f5708b7 ARM: 9029/1: Make iwmmxt.S support Clang's integrated assembler
This patch replaces 6 IWMMXT instructions Clang's integrated assembler
does not support in iwmmxt.S using macros, while making sure GNU
assembler still emit the same instructions. This should be easier than
providing full IWMMXT support in Clang.  This is one of the last bits of
kernel code that could be compiled but not assembled with clang. Once
all of it works with IAS, we no longer need to special-case 32-bit Arm
in Kbuild, or turn off CONFIG_IWMMXT when build-testing.

"Intel Wireless MMX Technology - Developer Guide - August, 2002" should
be referenced for the encoding schemes of these extensions.

Link: https://github.com/ClangBuiltLinux/linux/issues/975

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Jian Cai <jiancai@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-08 10:14:59 +00:00

48 lines
970 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __IWMMXT_H__
#define __IWMMXT_H__
.irp b, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
.set .LwR\b, \b
.set .Lr\b, \b
.endr
.set .LwCSSF, 0x2
.set .LwCASF, 0x3
.set .LwCGR0, 0x8
.set .LwCGR1, 0x9
.set .LwCGR2, 0xa
.set .LwCGR3, 0xb
.macro wldrd, reg:req, base:req, offset:req
.inst 0xedd00100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
.endm
.macro wldrw, reg:req, base:req, offset:req
.inst 0xfd900100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
.endm
.macro wstrd, reg:req, base:req, offset:req
.inst 0xedc00100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
.endm
.macro wstrw, reg:req, base:req, offset:req
.inst 0xfd800100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
.endm
#ifdef __clang__
#define wCon c1
.macro tmrc, dest:req, control:req
mrc p1, 0, \dest, \control, c0, 0
.endm
.macro tmcr, control:req, src:req
mcr p1, 0, \src, \control, c0, 0
.endm
#endif
#endif