cache-sh3.c

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/*
 * arch/sh/mm/cache-sh3.c
 *
 * Copyright (C) 1999, 2000  Niibe Yutaka
 * Copyright (C) 2002 Paul Mundt
 *
 * Released under the terms of the GNU GPL v2.0.
 */

#include <linux/init.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/threads.h>
#include <asm/addrspace.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>

/*
 * Write back the dirty D-caches, but not invalidate them.
 *
 * Is this really worth it, or should we just alias this routine
 * to __flush_purge_region too?
 *
 * START: Virtual Address (U0, P1, or P3)
 * SIZE: Size of the region.
 */

static void sh3__flush_wback_region(void *start, int size)
{
    unsigned long v, j;
    unsigned long begin, end;
    unsigned long flags;

    begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
    end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
        & ~(L1_CACHE_BYTES-1);

    for (v = begin; v < end; v+=L1_CACHE_BYTES) {
        unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
        for (j = 0; j < current_cpu_data.dcache.ways; j++) {
            unsigned long data, addr, p;

            p = __pa(v);
            addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
            local_irq_save(flags);
            data = __raw_readl(addr);

            if ((data & CACHE_PHYSADDR_MASK) ==
                (p & CACHE_PHYSADDR_MASK)) {
                data &= ~SH_CACHE_UPDATED;
                __raw_writel(data, addr);
                local_irq_restore(flags);
                break;
            }
            local_irq_restore(flags);
            addrstart += current_cpu_data.dcache.way_incr;
        }
    }
}

/*
 * Write back the dirty D-caches and invalidate them.
 *
 * START: Virtual Address (U0, P1, or P3)
 * SIZE: Size of the region.
 */
static void sh3__flush_purge_region(void *start, int size)
{
    unsigned long v;
    unsigned long begin, end;

    begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
    end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
        & ~(L1_CACHE_BYTES-1);

    for (v = begin; v < end; v+=L1_CACHE_BYTES) {
        unsigned long data, addr;

        data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
        addr = CACHE_OC_ADDRESS_ARRAY |
            (v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
        __raw_writel(data, addr);
    }
}

void __init sh3_cache_init(void)
{
    __flush_wback_region = sh3__flush_wback_region;
    __flush_purge_region = sh3__flush_purge_region;

    /*
     * No write back please
     *
     * Except I don't think there's any way to avoid the writeback.
     * So we just alias it to sh3__flush_purge_region(). dwmw2.
     */
    __flush_invalidate_region = sh3__flush_purge_region;
}