linux/arch/arm64/include/asm/sysreg.h
Suzuki K. Poulose 9ded63aaf8 arm64: Generalise msr_s/mrs_s operations
The system register encoding generated by sys_reg() works only
for MRS/MSR(Register) operations, as we hardcode Bit20 to 1 in
mrs_s/msr_s mask. This makes it unusable for generating instructions
accessing registers with Op0 < 2(e.g, PSTATE.x with Op0=0).

As per ARMv8 ARM, (Ref: ARMv8 ARM, Section: "System instruction class
encoding overview", C5.2, version:ARM DDI 0487A.f), the instruction
encoding reserves bits [20-19] for Op0.

This patch generalises the sys_reg, mrs_s and msr_s macros, so that
we could use them to access any of the supported system register.

Cc: James Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27 11:08:41 +01:00

83 lines
2.1 KiB
C

/*
* Macros for accessing system registers with older binutils.
*
* Copyright (C) 2014 ARM Ltd.
* Author: Catalin Marinas <catalin.marinas@arm.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_SYSREG_H
#define __ASM_SYSREG_H
#define SCTLR_EL1_CP15BEN (0x1 << 5)
#define SCTLR_EL1_SED (0x1 << 8)
/*
* ARMv8 ARM reserves the following encoding for system registers:
* (Ref: ARMv8 ARM, Section: "System instruction class encoding overview",
* C5.2, version:ARM DDI 0487A.f)
* [20-19] : Op0
* [18-16] : Op1
* [15-12] : CRn
* [11-8] : CRm
* [7-5] : Op2
*/
#define sys_reg(op0, op1, crn, crm, op2) \
((((op0)&3)<<19)|((op1)<<16)|((crn)<<12)|((crm)<<8)|((op2)<<5))
#ifdef __ASSEMBLY__
.irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30
.equ __reg_num_x\num, \num
.endr
.equ __reg_num_xzr, 31
.macro mrs_s, rt, sreg
.inst 0xd5200000|(\sreg)|(__reg_num_\rt)
.endm
.macro msr_s, sreg, rt
.inst 0xd5000000|(\sreg)|(__reg_num_\rt)
.endm
#else
asm(
" .irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n"
" .equ __reg_num_x\\num, \\num\n"
" .endr\n"
" .equ __reg_num_xzr, 31\n"
"\n"
" .macro mrs_s, rt, sreg\n"
" .inst 0xd5200000|(\\sreg)|(__reg_num_\\rt)\n"
" .endm\n"
"\n"
" .macro msr_s, sreg, rt\n"
" .inst 0xd5000000|(\\sreg)|(__reg_num_\\rt)\n"
" .endm\n"
);
static inline void config_sctlr_el1(u32 clear, u32 set)
{
u32 val;
asm volatile("mrs %0, sctlr_el1" : "=r" (val));
val &= ~clear;
val |= set;
asm volatile("msr sctlr_el1, %0" : : "r" (val));
}
#endif
#endif /* __ASM_SYSREG_H */