cache.c

/*
 * arch/sh/mm/pg-mmu.c
 *
 * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
 * Copyright (C) 2002 - 2009  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/highmem.h>
#include <linux/module.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>

void (*flush_cache_all)(void);
void (*flush_cache_mm)(struct mm_struct *mm);
void (*flush_cache_dup_mm)(struct mm_struct *mm);
void (*flush_cache_page)(struct vm_area_struct *vma,
				unsigned long addr, unsigned long pfn);
void (*flush_cache_range)(struct vm_area_struct *vma,
				 unsigned long start, unsigned long end);
void (*flush_dcache_page)(struct page *page);
void (*flush_icache_range)(unsigned long start, unsigned long end);
void (*flush_icache_page)(struct vm_area_struct *vma,
				 struct page *page);
void (*flush_cache_sigtramp)(unsigned long address);
void (*__flush_wback_region)(void *start, int size);
void (*__flush_purge_region)(void *start, int size);
void (*__flush_invalidate_region)(void *start, int size);

static inline void noop_flush_cache_all(void)
{
}

static inline void noop_flush_cache_mm(struct mm_struct *mm)
{
}

static inline void noop_flush_cache_page(struct vm_area_struct *vma,
				unsigned long addr, unsigned long pfn)
{
}

static inline void noop_flush_cache_range(struct vm_area_struct *vma,
				 unsigned long start, unsigned long end)
{
}

static inline void noop_flush_dcache_page(struct page *page)
{
}

static inline void noop_flush_icache_range(unsigned long start,
					   unsigned long end)
{
}

static inline void noop_flush_icache_page(struct vm_area_struct *vma,
					  struct page *page)
{
}

static inline void noop_flush_cache_sigtramp(unsigned long address)
{
}

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

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_dirty, &page->flags)) {
		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
		memcpy(vto, src, len);
		kunmap_coherent();
	} else {
		memcpy(dst, src, len);
		if (boot_cpu_data.dcache.n_aliases)
			set_bit(PG_dcache_dirty, &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_dirty, &page->flags)) {
		void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
		memcpy(dst, vfrom, len);
		kunmap_coherent();
	} else {
		memcpy(dst, src, len);
		if (boot_cpu_data.dcache.n_aliases)
			set_bit(PG_dcache_dirty, &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, KM_USER1);

	if (boot_cpu_data.dcache.n_aliases && page_mapped(from) &&
	    !test_bit(PG_dcache_dirty, &from->flags)) {
		vfrom = kmap_coherent(from, vaddr);
		copy_page(vto, vfrom);
		kunmap_coherent();
	} else {
		vfrom = kmap_atomic(from, KM_USER0);
		copy_page(vto, vfrom);
		kunmap_atomic(vfrom, KM_USER0);
	}

	if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
		__flush_wback_region(vto, PAGE_SIZE);

	kunmap_atomic(vto, KM_USER1);
	/* 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, KM_USER0);

	clear_page(kaddr);

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

	kunmap_atomic(kaddr, KM_USER0);
}
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) && page_mapping(page)) {
		int dirty = test_and_clear_bit(PG_dcache_dirty, &page->flags);
		if (dirty) {
			unsigned long addr = (unsigned long)page_address(page);

			if (pages_do_alias(addr, address & PAGE_MASK))
				__flush_wback_region((void *)addr, 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_dirty, &page->flags)) {
			void *kaddr;

			kaddr = kmap_coherent(page, vmaddr);
			__flush_wback_region((void *)kaddr, PAGE_SIZE);
			kunmap_coherent();
		} else
			__flush_wback_region((void *)addr, PAGE_SIZE);
	}
}

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

	flush_cache_all		= noop_flush_cache_all;
	flush_cache_mm		= noop_flush_cache_mm;
	flush_cache_dup_mm	= noop_flush_cache_mm;
	flush_cache_page	= noop_flush_cache_page;
	flush_cache_range	= noop_flush_cache_range;
	flush_dcache_page	= noop_flush_dcache_page;
	flush_icache_range	= noop_flush_icache_range;
	flush_icache_page	= noop_flush_icache_page;
	flush_cache_sigtramp	= noop_flush_cache_sigtramp;

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

	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();
	}

	emit_cache_params();
}