/*
 * arch/sh/mm/cache-sh2a.c
 *
 * Copyright (C) 2008 Yoshinori Sato
 *
 * Released under the terms of the GNU GPL v2.0.
 */

#include <linux/init.h>
#include <linux/mm.h>

#include <asm/cache.h>
#include <asm/addrspace.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
#include <asm/io.h>

/*
 * The maximum number of pages we support up to when doing ranged dcache
 * flushing. Anything exceeding this will simply flush the dcache in its
 * entirety.
 */
#define MAX_OCACHE_PAGES        32
#define MAX_ICACHE_PAGES        32

#ifdef CONFIG_CACHE_WRITEBACK
static void sh2a_flush_oc_line(unsigned long v, int way)
{
        unsigned long addr = (v & 0x000007f0) | (way << 11);
        unsigned long data;

        data = __raw_readl(CACHE_OC_ADDRESS_ARRAY | addr);
        if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) {
                data &= ~SH_CACHE_UPDATED;
                __raw_writel(data, CACHE_OC_ADDRESS_ARRAY | addr);
        }
}
#endif

static void sh2a_invalidate_line(unsigned long cache_addr, unsigned long v)
{
        /* Set associative bit to hit all ways */
        unsigned long addr = (v & 0x000007f0) | SH_CACHE_ASSOC;
        __raw_writel((addr & CACHE_PHYSADDR_MASK), cache_addr | addr);
}

/*
 * Write back the dirty D-caches, but not invalidate them.
 */
static void sh2a__flush_wback_region(void *start, int size)
{
#ifdef CONFIG_CACHE_WRITEBACK
        unsigned long v;
        unsigned long begin, end;
        unsigned long flags;
        int nr_ways;

        begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
        end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
                & ~(L1_CACHE_BYTES-1);
        nr_ways = current_cpu_data.dcache.ways;

        local_irq_save(flags);
        jump_to_uncached();

        /* If there are too many pages then flush the entire cache */
        if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
                begin = CACHE_OC_ADDRESS_ARRAY;
                end = begin + (nr_ways * current_cpu_data.dcache.way_size);

                for (v = begin; v < end; v += L1_CACHE_BYTES) {
                        unsigned long data = __raw_readl(v);
                        if (data & SH_CACHE_UPDATED)
                                __raw_writel(data & ~SH_CACHE_UPDATED, v);
                }
        } else {
                int way;
                for (way = 0; way < nr_ways; way++) {
                        for (v = begin; v < end; v += L1_CACHE_BYTES)
                                sh2a_flush_oc_line(v, way);
                }
        }

        back_to_cached();
        local_irq_restore(flags);
#endif
}

/*
 * Write back the dirty D-caches and invalidate them.
 */
static void sh2a__flush_purge_region(void *start, int size)
{
        unsigned long v;
        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);

        local_irq_save(flags);
        jump_to_uncached();

        for (v = begin; v < end; v+=L1_CACHE_BYTES) {
#ifdef CONFIG_CACHE_WRITEBACK
                int way;
                int nr_ways = current_cpu_data.dcache.ways;
                for (way = 0; way < nr_ways; way++)
                        sh2a_flush_oc_line(v, way);
#endif
                sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
        }

        back_to_cached();
        local_irq_restore(flags);
}

/*
 * Invalidate the D-caches, but no write back please
 */
static void sh2a__flush_invalidate_region(void *start, int size)
{
        unsigned long v;
        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);

        local_irq_save(flags);
        jump_to_uncached();

        /* If there are too many pages then just blow the cache */
        if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
                __raw_writel(__raw_readl(CCR) | CCR_OCACHE_INVALIDATE, CCR);
        } else {
                for (v = begin; v < end; v += L1_CACHE_BYTES)
                        sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
        }

        back_to_cached();
        local_irq_restore(flags);
}

/*
 * Write back the range of D-cache, and purge the I-cache.
 */
static void sh2a_flush_icache_range(void *args)
{
        struct flusher_data *data = args;
        unsigned long start, end;
        unsigned long v;
        unsigned long flags;

        start = data->addr1 & ~(L1_CACHE_BYTES-1);
        end = (data->addr2 + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1);

#ifdef CONFIG_CACHE_WRITEBACK
        sh2a__flush_wback_region((void *)start, end-start);
#endif

        local_irq_save(flags);
        jump_to_uncached();

        /* I-Cache invalidate */
        /* If there are too many pages then just blow the cache */
        if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) {
                __raw_writel(__raw_readl(CCR) | CCR_ICACHE_INVALIDATE, CCR);
        } else {
                for (v = start; v < end; v += L1_CACHE_BYTES)
                        sh2a_invalidate_line(CACHE_IC_ADDRESS_ARRAY, v);
        }

        back_to_cached();
        local_irq_restore(flags);
}

void __init sh2a_cache_init(void)
{
        local_flush_icache_range        = sh2a_flush_icache_range;

        __flush_wback_region            = sh2a__flush_wback_region;
        __flush_purge_region            = sh2a__flush_purge_region;
        __flush_invalidate_region       = sh2a__flush_invalidate_region;
}