linux_kernel/arch/arm64/mm/proc-macros.S

/*
 * Based on arch/arm/mm/proc-macros.S
 *
 * Copyright (C) 2012 ARM Ltd.
 *
 * 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/>.
 */

#include <asm/asm-offsets.h>
#include <asm/thread_info.h>

/*
 * vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
 */
	.macro	vma_vm_mm, rd, rn
	ldr	\rd, [\rn, #VMA_VM_MM]
	.endm

/*
 * mmid - get context id from mm pointer (mm->context.id)
 */
	.macro	mmid, rd, rn
	ldr	\rd, [\rn, #MM_CONTEXT_ID]
	.endm

/*
 * dcache_line_size - get the minimum D-cache line size from the CTR register.
 */
	.macro	dcache_line_size, reg, tmp
	mrs	\tmp, ctr_el0			// read CTR
	ubfm	\tmp, \tmp, #16, #19		// cache line size encoding
	mov	\reg, #4			// bytes per word
	lsl	\reg, \reg, \tmp		// actual cache line size
	.endm

/*
 * icache_line_size - get the minimum I-cache line size from the CTR register.
 */
	.macro	icache_line_size, reg, tmp
	mrs	\tmp, ctr_el0			// read CTR
	and	\tmp, \tmp, #0xf		// cache line size encoding
	mov	\reg, #4			// bytes per word
	lsl	\reg, \reg, \tmp		// actual cache line size
	.endm

/*
 * tcr_set_idmap_t0sz - update TCR.T0SZ so that we can load the ID map
 */
	.macro	tcr_set_idmap_t0sz, valreg, tmpreg
#ifndef CONFIG_ARM64_VA_BITS_48
	ldr_l	\tmpreg, idmap_t0sz
	bfi	\valreg, \tmpreg, #TCR_T0SZ_OFFSET, #TCR_TxSZ_WIDTH
#endif
	.endm

/*
 * Macro to perform a data cache maintenance for the interval
 * [kaddr, kaddr + size)
 *
 * 	op:		operation passed to dc instruction
 * 	domain:		domain used in dsb instruciton
 * 	kaddr:		starting virtual address of the region
 * 	size:		size of the region
 * 	Corrupts: 	kaddr, size, tmp1, tmp2
 */
	.macro dcache_by_line_op op, domain, kaddr, size, tmp1, tmp2
	dcache_line_size \tmp1, \tmp2
	add	\size, \kaddr, \size
	sub	\tmp2, \tmp1, #1
	bic	\kaddr, \kaddr, \tmp2
9998:	dc	\op, \kaddr
	add	\kaddr, \kaddr, \tmp1
	cmp	\kaddr, \size
	b.lo	9998b
	dsb	\domain
	.endm

/*
 * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present
 */
	.macro	reset_pmuserenr_el0, tmpreg
	mrs	\tmpreg, id_aa64dfr0_el1	// Check ID_AA64DFR0_EL1 PMUVer
	sbfx	\tmpreg, \tmpreg, #8, #4
	cmp	\tmpreg, #1			// Skip if no PMU present
	b.lt	9000f
	msr	pmuserenr_el0, xzr		// Disable PMU access from EL0
9000:
	.endm