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Diffstat (limited to 'arch/sh/mm/cache-sh7705.c')
| -rw-r--r-- | arch/sh/mm/cache-sh7705.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/sh/mm/cache-sh7705.c b/arch/sh/mm/cache-sh7705.c new file mode 100644 index 000000000..9b63a53a5 --- /dev/null +++ b/arch/sh/mm/cache-sh7705.c @@ -0,0 +1,194 @@ +/* + * 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/fs.h> +#include <linux/pagemap.h> +#include <linux/threads.h> +#include <asm/addrspace.h> +#include <asm/page.h> +#include <asm/processor.h> +#include <asm/cache.h> +#include <asm/io.h> +#include <linux/uaccess.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 = __raw_readl(addr); + + if ((data & v) == v) + __raw_writel(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. + */ +static void sh7705_flush_icache_range(void *args) +{ + struct flusher_data *data = args; + unsigned long start, end; + + start = data->addr1; + end = data->addr2; + + __flush_wback_region((void *)start, end - start); +} + +/* + * Writeback&Invalidate the D-cache of the page + */ +static void __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 = __raw_readl(addr) & (0x1ffffC00 | SH_CACHE_VALID); + if (data == phys) { + data &= ~(SH_CACHE_VALID | SH_CACHE_UPDATED); + __raw_writel(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) + */ +static void sh7705_flush_dcache_page(void *arg) +{ + struct page *page = arg; + struct address_space *mapping = page_mapping_file(page); + + if (mapping && !mapping_mapped(mapping)) + clear_bit(PG_dcache_clean, &page->flags); + else + __flush_dcache_page(__pa(page_address(page))); +} + +static void sh7705_flush_cache_all(void *args) +{ + unsigned long flags; + + local_irq_save(flags); + jump_to_uncached(); + + cache_wback_all(); + back_to_cached(); + local_irq_restore(flags); +} + +/* + * Write back and invalidate I/D-caches for the page. + * + * ADDRESS: Virtual Address (U0 address) + */ +static void sh7705_flush_cache_page(void *args) +{ + struct flusher_data *data = args; + unsigned long pfn = data->addr2; + + __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. + */ +static void sh7705_flush_icache_page(void *page) +{ + __flush_purge_region(page_address(page), PAGE_SIZE); +} + +void __init sh7705_cache_init(void) +{ + local_flush_icache_range = sh7705_flush_icache_range; + local_flush_dcache_page = sh7705_flush_dcache_page; + local_flush_cache_all = sh7705_flush_cache_all; + local_flush_cache_mm = sh7705_flush_cache_all; + local_flush_cache_dup_mm = sh7705_flush_cache_all; + local_flush_cache_range = sh7705_flush_cache_all; + local_flush_cache_page = sh7705_flush_cache_page; + local_flush_icache_page = sh7705_flush_icache_page; +} |