copypage-feroceon.c

Go to the documentation of this file.

/*
 *  linux/arch/arm/mm/copypage-feroceon.S
 *
 *  Copyright (C) 2008 Marvell Semiconductors
 *
 * 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 handles copy_user_highpage and clear_user_page on Feroceon
 * more optimally than the generic implementations.
 */
#include <linux/init.h>
#include <linux/highmem.h>

static void __naked
feroceon_copy_user_page(void *kto, const void *kfrom)
{
    asm("\
    stmfd   sp!, {r4-r9, lr}        \n\
    mov ip, %2              \n\
1:  mov lr, r1              \n\
    ldmia   r1!, {r2 - r9}          \n\
    pld [lr, #32]           \n\
    pld [lr, #64]           \n\
    pld [lr, #96]           \n\
    pld [lr, #128]          \n\
    pld [lr, #160]          \n\
    pld [lr, #192]          \n\
    pld [lr, #224]          \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    ldmia   r1!, {r2 - r9}          \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    stmia   r0, {r2 - r9}           \n\
    subs    ip, ip, #(32 * 8)       \n\
    mcr p15, 0, r0, c7, c14, 1      @ clean and invalidate D line\n\
    add r0, r0, #32         \n\
    bne 1b              \n\
    mcr p15, 0, ip, c7, c10, 4      @ drain WB\n\
    ldmfd   sp!, {r4-r9, pc}"
    :
    : "r" (kto), "r" (kfrom), "I" (PAGE_SIZE));
}

void feroceon_copy_user_highpage(struct page *to, struct page *from,
    unsigned long vaddr, struct vm_area_struct *vma)
{
    void *kto, *kfrom;

    kto = kmap_atomic(to);
    kfrom = kmap_atomic(from);
    flush_cache_page(vma, vaddr, page_to_pfn(from));
    feroceon_copy_user_page(kto, kfrom);
    kunmap_atomic(kfrom);
    kunmap_atomic(kto);
}

void feroceon_clear_user_highpage(struct page *page, unsigned long vaddr)
{
    void *ptr, *kaddr = kmap_atomic(page);
    asm volatile ("\
    mov r1, %2              \n\
    mov r2, #0              \n\
    mov r3, #0              \n\
    mov r4, #0              \n\
    mov r5, #0              \n\
    mov r6, #0              \n\
    mov r7, #0              \n\
    mov ip, #0              \n\
    mov lr, #0              \n\
1:  stmia   %0, {r2-r7, ip, lr}     \n\
    subs    r1, r1, #1          \n\
    mcr p15, 0, %0, c7, c14, 1      @ clean and invalidate D line\n\
    add %0, %0, #32         \n\
    bne 1b              \n\
    mcr p15, 0, r1, c7, c10, 4      @ drain WB"
    : "=r" (ptr)
    : "0" (kaddr), "I" (PAGE_SIZE / 32)
    : "r1", "r2", "r3", "r4", "r5", "r6", "r7", "ip", "lr");
    kunmap_atomic(kaddr);
}

struct cpu_user_fns feroceon_user_fns __initdata = {
    .cpu_clear_user_highpage = feroceon_clear_user_highpage,
    .cpu_copy_user_highpage = feroceon_copy_user_highpage,
};