diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/mm/cache-sh7705.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sh/mm/cache-sh7705.c')
-rw-r--r-- | arch/sh/mm/cache-sh7705.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/arch/sh/mm/cache-sh7705.c b/arch/sh/mm/cache-sh7705.c new file mode 100644 index 000000000000..ad8ed7d41e16 --- /dev/null +++ b/arch/sh/mm/cache-sh7705.c @@ -0,0 +1,206 @@ +/* + * 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 */ + +#define __pte_offset(address) \ + ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +#define pte_offset(dir, address) ((pte_t *) pmd_page_kernel(*(dir)) + \ + __pte_offset(address)) + +static inline void cache_wback_all(void) +{ + unsigned long ways, waysize, addrstart; + + ways = cpu_data->dcache.ways; + waysize = cpu_data->dcache.sets; + waysize <<= cpu_data->dcache.entry_shift; + + addrstart = CACHE_OC_ADDRESS_ARRAY; + + do { + unsigned long addr; + + for (addr = addrstart; + addr < addrstart + waysize; + addr += 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 += 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 __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_P2(); + + ways = cpu_data->dcache.ways; + waysize = cpu_data->dcache.sets; + waysize <<= cpu_data->dcache.entry_shift; + + addrstart = CACHE_OC_ADDRESS_ARRAY; + + do { + unsigned long addr; + + for (addr = addrstart; + addr < addrstart + waysize; + addr += 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 += cpu_data->dcache.way_incr; + } while (--ways); + + back_to_P1(); + 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 flush_cache_all(void) +{ + unsigned long flags; + + local_irq_save(flags); + jump_to_P2(); + + cache_wback_all(); + back_to_P1(); + 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); +} + |