diff options
Diffstat (limited to 'arch/sh/mm/cache-sh4.c')
| -rw-r--r-- | arch/sh/mm/cache-sh4.c | 220 |
1 files changed, 130 insertions, 90 deletions
diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index 2203bd6aadb3..aa4f62f0e374 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -2,29 +2,31 @@ * arch/sh/mm/cache-sh4.c * * Copyright (C) 1999, 2000, 2002 Niibe Yutaka - * Copyright (C) 2001, 2002, 2003, 2004, 2005 Paul Mundt + * Copyright (C) 2001 - 2006 Paul Mundt * Copyright (C) 2003 Richard Curnow * * 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 maximum number of pages we support up to when doing ranged dcache + * flushing. Anything exceeding this will simply flush the dcache in its + * entirety. + */ +#define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */ + static void __flush_dcache_segment_1way(unsigned long start, unsigned long extent); static void __flush_dcache_segment_2way(unsigned long start, @@ -219,14 +221,14 @@ void flush_cache_sigtramp(unsigned long addr) static inline void flush_cache_4096(unsigned long start, unsigned long phys) { - unsigned long flags; - /* * All types of SH-4 require PC to be in P2 to operate on the I-cache. * Some types of SH-4 require PC to be in P2 to operate on the D-cache. */ - if ((cpu_data->flags & CPU_HAS_P2_FLUSH_BUG) - || start < CACHE_OC_ADDRESS_ARRAY) { + if ((cpu_data->flags & CPU_HAS_P2_FLUSH_BUG) || + (start < CACHE_OC_ADDRESS_ARRAY)) { + unsigned long flags; + local_irq_save(flags); __flush_cache_4096(start | SH_CACHE_ASSOC, P1SEGADDR(phys), 0x20000000); @@ -257,6 +259,7 @@ void flush_dcache_page(struct page *page) wmb(); } +/* TODO: Selective icache invalidation through IC address array.. */ static inline void flush_icache_all(void) { unsigned long flags, ccr; @@ -290,19 +293,121 @@ void flush_cache_all(void) flush_icache_all(); } +static void __flush_cache_mm(struct mm_struct *mm, unsigned long start, + unsigned long end) +{ + unsigned long d = 0, p = start & PAGE_MASK; + unsigned long alias_mask = cpu_data->dcache.alias_mask; + unsigned long n_aliases = cpu_data->dcache.n_aliases; + unsigned long select_bit; + unsigned long all_aliases_mask; + unsigned long addr_offset; + pgd_t *dir; + pmd_t *pmd; + pud_t *pud; + pte_t *pte; + int i; + + dir = pgd_offset(mm, p); + pud = pud_offset(dir, p); + pmd = pmd_offset(pud, p); + end = PAGE_ALIGN(end); + + all_aliases_mask = (1 << n_aliases) - 1; + + do { + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) { + p &= PMD_MASK; + p += PMD_SIZE; + pmd++; + + continue; + } + + pte = pte_offset_kernel(pmd, p); + + do { + unsigned long phys; + pte_t entry = *pte; + + if (!(pte_val(entry) & _PAGE_PRESENT)) { + pte++; + p += PAGE_SIZE; + continue; + } + + phys = pte_val(entry) & PTE_PHYS_MASK; + + if ((p ^ phys) & alias_mask) { + d |= 1 << ((p & alias_mask) >> PAGE_SHIFT); + d |= 1 << ((phys & alias_mask) >> PAGE_SHIFT); + + if (d == all_aliases_mask) + goto loop_exit; + } + + pte++; + p += PAGE_SIZE; + } while (p < end && ((unsigned long)pte & ~PAGE_MASK)); + pmd++; + } while (p < end); + +loop_exit: + addr_offset = 0; + select_bit = 1; + + for (i = 0; i < n_aliases; i++) { + if (d & select_bit) { + (*__flush_dcache_segment_fn)(addr_offset, PAGE_SIZE); + wmb(); + } + + select_bit <<= 1; + addr_offset += PAGE_SIZE; + } +} + +/* + * Note : (RPC) since the caches are physically tagged, the only point + * of flush_cache_mm for SH-4 is to get rid of aliases from the + * D-cache. The assumption elsewhere, e.g. flush_cache_range, is that + * lines can stay resident so long as the virtual address they were + * accessed with (hence cache set) is in accord with the physical + * address (i.e. tag). It's no different here. So I reckon we don't + * need to flush the I-cache, since aliases don't matter for that. We + * should try that. + * + * Caller takes mm->mmap_sem. + */ void flush_cache_mm(struct mm_struct *mm) { /* - * Note : (RPC) since the caches are physically tagged, the only point - * of flush_cache_mm for SH-4 is to get rid of aliases from the - * D-cache. The assumption elsewhere, e.g. flush_cache_range, is that - * lines can stay resident so long as the virtual address they were - * accessed with (hence cache set) is in accord with the physical - * address (i.e. tag). It's no different here. So I reckon we don't - * need to flush the I-cache, since aliases don't matter for that. We - * should try that. + * If cache is only 4k-per-way, there are never any 'aliases'. Since + * the cache is physically tagged, the data can just be left in there. + */ + if (cpu_data->dcache.n_aliases == 0) + return; + + /* + * Don't bother groveling around the dcache for the VMA ranges + * if there are too many PTEs to make it worthwhile. */ - flush_cache_all(); + if (mm->nr_ptes >= MAX_DCACHE_PAGES) + flush_dcache_all(); + else { + struct vm_area_struct *vma; + + /* + * In this case there are reasonably sized ranges to flush, + * iterate through the VMA list and take care of any aliases. + */ + for (vma = mm->mmap; vma; vma = vma->vm_next) + __flush_cache_mm(mm, vma->vm_start, vma->vm_end); + } + + /* Only touch the icache if one of the VMAs has VM_EXEC set. */ + if (mm->exec_vm) + flush_icache_all(); } /* @@ -311,7 +416,8 @@ void flush_cache_mm(struct mm_struct *mm) * ADDR: Virtual Address (U0 address) * PFN: Physical page number */ -void flush_cache_page(struct vm_area_struct *vma, unsigned long address, unsigned long pfn) +void flush_cache_page(struct vm_area_struct *vma, unsigned long address, + unsigned long pfn) { unsigned long phys = pfn << PAGE_SHIFT; unsigned int alias_mask; @@ -358,87 +464,22 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long address, unsigne void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { - unsigned long d = 0, p = start & PAGE_MASK; - unsigned long alias_mask = cpu_data->dcache.alias_mask; - unsigned long n_aliases = cpu_data->dcache.n_aliases; - unsigned long select_bit; - unsigned long all_aliases_mask; - unsigned long addr_offset; - unsigned long phys; - pgd_t *dir; - pmd_t *pmd; - pud_t *pud; - pte_t *pte; - pte_t entry; - int i; - /* * If cache is only 4k-per-way, there are never any 'aliases'. Since * the cache is physically tagged, the data can just be left in there. */ - if (n_aliases == 0) + if (cpu_data->dcache.n_aliases == 0) return; - all_aliases_mask = (1 << n_aliases) - 1; - /* * Don't bother with the lookup and alias check if we have a * wide range to cover, just blow away the dcache in its * entirety instead. -- PFM. */ - if (((end - start) >> PAGE_SHIFT) >= 64) { + if (((end - start) >> PAGE_SHIFT) >= MAX_DCACHE_PAGES) flush_dcache_all(); - - if (vma->vm_flags & VM_EXEC) - flush_icache_all(); - - return; - } - - dir = pgd_offset(vma->vm_mm, p); - pud = pud_offset(dir, p); - pmd = pmd_offset(pud, p); - end = PAGE_ALIGN(end); - - do { - if (pmd_none(*pmd) || pmd_bad(*pmd)) { - p &= ~((1 << PMD_SHIFT) - 1); - p += (1 << PMD_SHIFT); - pmd++; - - continue; - } - - pte = pte_offset_kernel(pmd, p); - - do { - entry = *pte; - - if ((pte_val(entry) & _PAGE_PRESENT)) { - phys = pte_val(entry) & PTE_PHYS_MASK; - - if ((p ^ phys) & alias_mask) { - d |= 1 << ((p & alias_mask) >> PAGE_SHIFT); - d |= 1 << ((phys & alias_mask) >> PAGE_SHIFT); - - if (d == all_aliases_mask) - goto loop_exit; - } - } - - pte++; - p += PAGE_SIZE; - } while (p < end && ((unsigned long)pte & ~PAGE_MASK)); - pmd++; - } while (p < end); - -loop_exit: - for (i = 0, select_bit = 0x1, addr_offset = 0x0; i < n_aliases; - i++, select_bit <<= 1, addr_offset += PAGE_SIZE) - if (d & select_bit) { - (*__flush_dcache_segment_fn)(addr_offset, PAGE_SIZE); - wmb(); - } + else + __flush_cache_mm(vma->vm_mm, start, end); if (vma->vm_flags & VM_EXEC) { /* @@ -731,4 +772,3 @@ static void __flush_dcache_segment_4way(unsigned long start, a3 += linesz; } while (a0 < a0e); } - |