/*
 * arch/sh/mm/cache.c
 *
 * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
 * Copyright (C) 2002 - 2010  Paul Mundt
 *
 * Released under the terms of the GNU GPL v2.0.
 */
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>

void (*local_flush_cache_all)(void *args) = cache_noop;
void (*local_flush_cache_mm)(void *args) = cache_noop;
void (*local_flush_cache_dup_mm)(void *args) = cache_noop;
void (*local_flush_cache_page)(void *args) = cache_noop;
void (*local_flush_cache_range)(void *args) = cache_noop;
void (*local_flush_dcache_page)(void *args) = cache_noop;
void (*local_flush_icache_range)(void *args) = cache_noop;
void (*local_flush_icache_page)(void *args) = cache_noop;
void (*local_flush_cache_sigtramp)(void *args) = cache_noop;

void (*__flush_wback_region)(void *start, int size);
EXPORT_SYMBOL(__flush_wback_region);
void (*__flush_purge_region)(void *start, int size);
EXPORT_SYMBOL(__flush_purge_region);
void (*__flush_invalidate_region)(void *start, int size);
EXPORT_SYMBOL(__flush_invalidate_region);

static inline void noop__flush_region(void *start, int size)
{
}

static inline void cacheop_on_each_cpu(void (*func) (void *info), void *info,
                                   int wait)
{
        preempt_disable();

        /*
         * It's possible that this gets called early on when IRQs are
         * still disabled due to ioremapping by the boot CPU, so don't
         * even attempt IPIs unless there are other CPUs online.
         */
        if (num_online_cpus() > 1)
                smp_call_function(func, info, wait);

        func(info);

        preempt_enable();
}

void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
                       unsigned long vaddr, void *dst, const void *src,
                       unsigned long len)
{
        if (boot_cpu_data.dcache.n_aliases && page_mapped(page) &&
            test_bit(PG_dcache_clean, &page->flags)) {
                void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
                memcpy(vto, src, len);
                kunmap_coherent(vto);
        } else {
                memcpy(dst, src, len);
                if (boot_cpu_data.dcache.n_aliases)
                        clear_bit(PG_dcache_clean, &page->flags);
        }

        if (vma->vm_flags & VM_EXEC)
                flush_cache_page(vma, vaddr, page_to_pfn(page));
}

void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
                         unsigned long vaddr, void *dst, const void *src,
                         unsigned long len)
{
        if (boot_cpu_data.dcache.n_aliases && page_mapped(page) &&
            test_bit(PG_dcache_clean, &page->flags)) {
                void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
                memcpy(dst, vfrom, len);
                kunmap_coherent(vfrom);
        } else {
                memcpy(dst, src, len);
                if (boot_cpu_data.dcache.n_aliases)
                        clear_bit(PG_dcache_clean, &page->flags);
        }
}

void copy_user_highpage(struct page *to, struct page *from,
                        unsigned long vaddr, struct vm_area_struct *vma)
{
        void *vfrom, *vto;

        vto = kmap_atomic(to);

        if (boot_cpu_data.dcache.n_aliases && page_mapped(from) &&
            test_bit(PG_dcache_clean, &from->flags)) {
                vfrom = kmap_coherent(from, vaddr);
                copy_page(vto, vfrom);
                kunmap_coherent(vfrom);
        } else {
                vfrom = kmap_atomic(from);
                copy_page(vto, vfrom);
                kunmap_atomic(vfrom);
        }

        if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK) ||
            (vma->vm_flags & VM_EXEC))
                __flush_purge_region(vto, PAGE_SIZE);

        kunmap_atomic(vto);
        /* Make sure this page is cleared on other CPU's too before using it */
        smp_wmb();
}
EXPORT_SYMBOL(copy_user_highpage);

void clear_user_highpage(struct page *page, unsigned long vaddr)
{
        void *kaddr = kmap_atomic(page);

        clear_page(kaddr);

        if (pages_do_alias((unsigned long)kaddr, vaddr & PAGE_MASK))
                __flush_purge_region(kaddr, PAGE_SIZE);

        kunmap_atomic(kaddr);
}
EXPORT_SYMBOL(clear_user_highpage);

void __update_cache(struct vm_area_struct *vma,
                    unsigned long address, pte_t pte)
{
        struct page *page;
        unsigned long pfn = pte_pfn(pte);

        if (!boot_cpu_data.dcache.n_aliases)
                return;

        page = pfn_to_page(pfn);
        if (pfn_valid(pfn)) {
                int dirty = !test_and_set_bit(PG_dcache_clean, &page->flags);
                if (dirty)
                        __flush_purge_region(page_address(page), PAGE_SIZE);
        }
}

void __flush_anon_page(struct page *page, unsigned long vmaddr)
{
        unsigned long addr = (unsigned long) page_address(page);

        if (pages_do_alias(addr, vmaddr)) {
                if (boot_cpu_data.dcache.n_aliases && page_mapped(page) &&
                    test_bit(PG_dcache_clean, &page->flags)) {
                        void *kaddr;

                        kaddr = kmap_coherent(page, vmaddr);
                        /* XXX.. For now kunmap_coherent() does a purge */
                        /* __flush_purge_region((void *)kaddr, PAGE_SIZE); */
                        kunmap_coherent(kaddr);
                } else
                        __flush_purge_region((void *)addr, PAGE_SIZE);
        }
}

void flush_cache_all(void)
{
        cacheop_on_each_cpu(local_flush_cache_all, NULL, 1);
}
EXPORT_SYMBOL(flush_cache_all);

void flush_cache_mm(struct mm_struct *mm)
{
        if (boot_cpu_data.dcache.n_aliases == 0)
                return;

        cacheop_on_each_cpu(local_flush_cache_mm, mm, 1);
}

void flush_cache_dup_mm(struct mm_struct *mm)
{
        if (boot_cpu_data.dcache.n_aliases == 0)
                return;

        cacheop_on_each_cpu(local_flush_cache_dup_mm, mm, 1);
}

void flush_cache_page(struct vm_area_struct *vma, unsigned long addr,
                      unsigned long pfn)
{
        struct flusher_data data;

        data.vma = vma;
        data.addr1 = addr;
        data.addr2 = pfn;

        cacheop_on_each_cpu(local_flush_cache_page, (void *)&data, 1);
}

void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
                       unsigned long end)
{
        struct flusher_data data;

        data.vma = vma;
        data.addr1 = start;
        data.addr2 = end;

        cacheop_on_each_cpu(local_flush_cache_range, (void *)&data, 1);
}
EXPORT_SYMBOL(flush_cache_range);

void flush_dcache_page(struct page *page)
{
        cacheop_on_each_cpu(local_flush_dcache_page, page, 1);
}
EXPORT_SYMBOL(flush_dcache_page);

void flush_icache_range(unsigned long start, unsigned long end)
{
        struct flusher_data data;

        data.vma = NULL;
        data.addr1 = start;
        data.addr2 = end;

        cacheop_on_each_cpu(local_flush_icache_range, (void *)&data, 1);
}
EXPORT_SYMBOL(flush_icache_range);

void flush_icache_page(struct vm_area_struct *vma, struct page *page)
{
        /* Nothing uses the VMA, so just pass the struct page along */
        cacheop_on_each_cpu(local_flush_icache_page, page, 1);
}

void flush_cache_sigtramp(unsigned long address)
{
        cacheop_on_each_cpu(local_flush_cache_sigtramp, (void *)address, 1);
}

static void compute_alias(struct cache_info *c)
{
        c->alias_mask = ((c->sets - 1) << c->entry_shift) & ~(PAGE_SIZE - 1);
        c->n_aliases = c->alias_mask ? (c->alias_mask >> PAGE_SHIFT) + 1 : 0;
}

static void __init emit_cache_params(void)
{
        printk(KERN_NOTICE "I-cache : n_ways=%d n_sets=%d way_incr=%d\n",
                boot_cpu_data.icache.ways,
                boot_cpu_data.icache.sets,
                boot_cpu_data.icache.way_incr);
        printk(KERN_NOTICE "I-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
                boot_cpu_data.icache.entry_mask,
                boot_cpu_data.icache.alias_mask,
                boot_cpu_data.icache.n_aliases);
        printk(KERN_NOTICE "D-cache : n_ways=%d n_sets=%d way_incr=%d\n",
                boot_cpu_data.dcache.ways,
                boot_cpu_data.dcache.sets,
                boot_cpu_data.dcache.way_incr);
        printk(KERN_NOTICE "D-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
                boot_cpu_data.dcache.entry_mask,
                boot_cpu_data.dcache.alias_mask,
                boot_cpu_data.dcache.n_aliases);

        /*
         * Emit Secondary Cache parameters if the CPU has a probed L2.
         */
        if (boot_cpu_data.flags & CPU_HAS_L2_CACHE) {
                printk(KERN_NOTICE "S-cache : n_ways=%d n_sets=%d way_incr=%d\n",
                        boot_cpu_data.scache.ways,
                        boot_cpu_data.scache.sets,
                        boot_cpu_data.scache.way_incr);
                printk(KERN_NOTICE "S-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
                        boot_cpu_data.scache.entry_mask,
                        boot_cpu_data.scache.alias_mask,
                        boot_cpu_data.scache.n_aliases);
        }
}

void __init cpu_cache_init(void)
{
        unsigned int cache_disabled = 0;

#ifdef SH_CCR
        cache_disabled = !(__raw_readl(SH_CCR) & CCR_CACHE_ENABLE);
#endif

        compute_alias(&boot_cpu_data.icache);
        compute_alias(&boot_cpu_data.dcache);
        compute_alias(&boot_cpu_data.scache);

        __flush_wback_region            = noop__flush_region;
        __flush_purge_region            = noop__flush_region;
        __flush_invalidate_region       = noop__flush_region;

        /*
         * No flushing is necessary in the disabled cache case so we can
         * just keep the noop functions in local_flush_..() and __flush_..()
         */
        if (unlikely(cache_disabled))
                goto skip;

        if (boot_cpu_data.family == CPU_FAMILY_SH2) {
                extern void __weak sh2_cache_init(void);

                sh2_cache_init();
        }

        if (boot_cpu_data.family == CPU_FAMILY_SH2A) {
                extern void __weak sh2a_cache_init(void);

                sh2a_cache_init();
        }

        if (boot_cpu_data.family == CPU_FAMILY_SH3) {
                extern void __weak sh3_cache_init(void);

                sh3_cache_init();

                if ((boot_cpu_data.type == CPU_SH7705) &&
                    (boot_cpu_data.dcache.sets == 512)) {
                        extern void __weak sh7705_cache_init(void);

                        sh7705_cache_init();
                }
        }

        if ((boot_cpu_data.family == CPU_FAMILY_SH4) ||
            (boot_cpu_data.family == CPU_FAMILY_SH4A) ||
            (boot_cpu_data.family == CPU_FAMILY_SH4AL_DSP)) {
                extern void __weak sh4_cache_init(void);

                sh4_cache_init();

                if ((boot_cpu_data.type == CPU_SH7786) ||
                    (boot_cpu_data.type == CPU_SHX3)) {
                        extern void __weak shx3_cache_init(void);

                        shx3_cache_init();
                }
        }

        if (boot_cpu_data.family == CPU_FAMILY_SH5) {
                extern void __weak sh5_cache_init(void);

                sh5_cache_init();
        }

skip:
        emit_cache_params();
}