linux_kernel/arch/arm64/include/asm/sysreg.h

/*
 * 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

#include <asm/opcodes.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))

#define REG_PSTATE_PAN_IMM                     sys_reg(0, 0, 4, 0, 4)
#define SCTLR_EL1_SPAN                         (1 << 23)

#define SET_PSTATE_PAN(x) __inst_arm(0xd5000000 | REG_PSTATE_PAN_IMM |\
				     (!!x)<<8 | 0x1f)

#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 */