arch/arm/mm/tlb-v6.S

root/arch/arm/mm/tlb-v6.S
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  linux/arch/arm/mm/tlb-v6.S
 *
 *  Copyright (C) 1997-2002 Russell King
 *
 *  ARM architecture version 6 TLB handling functions.
 *  These assume a split I/D TLB.
 */
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/cfi_types.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
#include <asm/page.h>
#include <asm/tlbflush.h>
#include "proc-macros.S"

#define HARVARD_TLB

.arch armv6

/*
 *      v6wbi_flush_user_tlb_range(start, end, vma)
 *
 *      Invalidate a range of TLB entries in the specified address space.
 *
 *      - start - start address (may not be aligned)
 *      - end   - end address (exclusive, may not be aligned)
 *      - vma   - vm_area_struct describing address range
 *
 *      It is assumed that:
 *      - the "Invalidate single entry" instruction will invalidate
 *        both the I and the D TLBs on Harvard-style TLBs
 */
SYM_TYPED_FUNC_START(v6wbi_flush_user_tlb_range)
        vma_vm_mm r3, r2                        @ get vma->vm_mm
        mov     ip, #0
        mmid    r3, r3                          @ get vm_mm->context.id
        mcr     p15, 0, ip, c7, c10, 4          @ drain write buffer
        mov     r0, r0, lsr #PAGE_SHIFT         @ align address
        mov     r1, r1, lsr #PAGE_SHIFT
        asid    r3, r3                          @ mask ASID
        orr     r0, r3, r0, lsl #PAGE_SHIFT     @ Create initial MVA
        mov     r1, r1, lsl #PAGE_SHIFT
        vma_vm_flags r2, r2                     @ get vma->vm_flags
1:
#ifdef HARVARD_TLB
        mcr     p15, 0, r0, c8, c6, 1           @ TLB invalidate D MVA (was 1)
        tst     r2, #VM_EXEC                    @ Executable area ?
        mcrne   p15, 0, r0, c8, c5, 1           @ TLB invalidate I MVA (was 1)
#else
        mcr     p15, 0, r0, c8, c7, 1           @ TLB invalidate MVA (was 1)
#endif
        add     r0, r0, #PAGE_SZ
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, ip, c7, c10, 4          @ data synchronization barrier
        ret     lr
SYM_FUNC_END(v6wbi_flush_user_tlb_range)

/*
 *      v6wbi_flush_kern_tlb_range(start,end)
 *
 *      Invalidate a range of kernel TLB entries
 *
 *      - start - start address (may not be aligned)
 *      - end   - end address (exclusive, may not be aligned)
 */
SYM_TYPED_FUNC_START(v6wbi_flush_kern_tlb_range)
        mov     r2, #0
        mcr     p15, 0, r2, c7, c10, 4          @ drain write buffer
        mov     r0, r0, lsr #PAGE_SHIFT         @ align address
        mov     r1, r1, lsr #PAGE_SHIFT
        mov     r0, r0, lsl #PAGE_SHIFT
        mov     r1, r1, lsl #PAGE_SHIFT
1:
#ifdef HARVARD_TLB
        mcr     p15, 0, r0, c8, c6, 1           @ TLB invalidate D MVA
        mcr     p15, 0, r0, c8, c5, 1           @ TLB invalidate I MVA
#else
        mcr     p15, 0, r0, c8, c7, 1           @ TLB invalidate MVA
#endif
        add     r0, r0, #PAGE_SZ
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, r2, c7, c10, 4          @ data synchronization barrier
        mcr     p15, 0, r2, c7, c5, 4           @ prefetch flush (isb)
        ret     lr
SYM_FUNC_END(v6wbi_flush_kern_tlb_range)
Linux
