/*
* arch/sh/mm/cache-sh7705.c
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2004 Alex Song
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
*/
#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>
/*
* The 32KB cache on the SH7705 suffers from the same synonym problem
* as SH4 CPUs
*/
static inline void cache_wback_all(void)
{
unsigned long ways, waysize, addrstart;
ways = current_cpu_data.dcache.ways;
waysize = current_cpu_data.dcache.sets;
waysize <<= current_cpu_data.dcache.entry_shift;
addrstart = CACHE_OC_ADDRESS_ARRAY;
do {
unsigned long addr;
for (addr = addrstart;
addr < addrstart + waysize;
addr += current_cpu_data.dcache.linesz) {
unsigned long data;
int v = SH_CACHE_UPDATED | SH_CACHE_VALID;
data = ctrl_inl(addr);
if ((data & v) == v)
ctrl_outl(data & ~v, addr);
}
addrstart += current_cpu_data.dcache.way_incr;
} while (--ways);
}
/*
* Write back the range of D-cache, and purge the I-cache.
*
* Called from kernel/module.c:sys_init_module and routine for a.out format.
*/
void flush_icache_range(unsigned long start, unsigned long end)
{
__flush_wback_region((void *)start, end - start);
}
/*
* Writeback&Invalidate the D-cache of the page
*/
static void __uses_jump_to_uncached __flush_dcache_page(unsigned long phys)
{
unsigned long ways, waysize, addrstart;
unsigned long flags;
phys |= SH_CACHE_VALID;
/*
* Here, phys is the physical address of the page. We check all the
* tags in the cache for those with the same page number as this page
* (by masking off the lowest 2 bits of the 19-bit tag; these bits are
* derived from the offset within in the 4k page). Matching valid
* entries are invalidated.
*
* Since 2 bits of the cache index are derived from the virtual page
* number, knowing this would reduce the number of cache entries to be
* searched by a factor of 4. However this function exists to deal with
* potential cache aliasing, therefore the optimisation is probably not
* possible.
*/
local_irq_save(flags);
jump_to_uncached();
ways = current_cpu_data.dcache.ways;
waysize = current_cpu_data.dcache.sets;
waysize <<= current_cpu_data.dcache.entry_shift;
addrstart = CACHE_OC_ADDRESS_ARRAY;
do {
unsigned long addr;
for (addr = addrstart;
addr < addrstart + waysize;
addr += current_cpu_data.dcache.linesz) {
unsigned long data;
data = ctrl_inl(addr) & (0x1ffffC00 | SH_CACHE_VALID);
if (data == phys) {
data &= ~(SH_CACHE_VALID | SH_CACHE_UPDATED);
ctrl_outl(data, addr);
}
}
addrstart += current_cpu_data.dcache.way_incr;
} while (--ways);
back_to_cached();
local_irq_restore(flags);
}
/*
* Write back & invalidate the D-cache of the page.
* (To avoid "alias" issues)
*/
void flush_dcache_page(struct page *page)
{
if (test_bit(PG_mapped, &page->flags))
__flush_dcache_page(PHYSADDR(page_address(page)));
}
void __uses_jump_to_uncached flush_cache_all(void)
{
unsigned long flags;
local_irq_save(flags);
jump_to_uncached();
cache_wback_all();
back_to_cached();
local_irq_restore(flags);
}
void flush_cache_mm(struct mm_struct *mm)
{
/* Is there any good way? */
/* XXX: possibly call flush_cache_range for each vm area */
flush_cache_all();
}
/*
* Write back and invalidate D-caches.
*
* START, END: Virtual Address (U0 address)
*
* NOTE: We need to flush the _physical_ page entry.
* Flushing the cache lines for U0 only isn't enough.
* We need to flush for P1 too, which may contain aliases.
*/
void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
/*
* We could call flush_cache_page for the pages of these range,
* but it's not efficient (scan the caches all the time...).
*
* We can't use A-bit magic, as there's the case we don't have
* valid entry on TLB.
*/
flush_cache_all();
}
/*
* Write back and invalidate I/D-caches for the page.
*
* ADDRESS: Virtual Address (U0 address)
*/
void flush_cache_page(struct vm_area_struct *vma, unsigned long address,
unsigned long pfn)
{
__flush_dcache_page(pfn << PAGE_SHIFT);
}
/*
* This is called when a page-cache page is about to be mapped into a
* user process' address space. It offers an opportunity for a
* port to ensure d-cache/i-cache coherency if necessary.
*
* Not entirely sure why this is necessary on SH3 with 32K cache but
* without it we get occasional "Memory fault" when loading a program.
*/
void flush_icache_page(struct vm_area_struct *vma, struct page *page)
{
__flush_purge_region(page_address(page), PAGE_SIZE);
}
