diff options
Diffstat (limited to 'arch/sh/mm/cache-sh4.c')
-rw-r--r-- | arch/sh/mm/cache-sh4.c | 504 |
1 files changed, 79 insertions, 425 deletions
diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index a98c7d8984f..56dd55a1b13 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -2,7 +2,7 @@ * arch/sh/mm/cache-sh4.c * * Copyright (C) 1999, 2000, 2002 Niibe Yutaka - * Copyright (C) 2001 - 2007 Paul Mundt + * Copyright (C) 2001 - 2009 Paul Mundt * Copyright (C) 2003 Richard Curnow * Copyright (c) 2007 STMicroelectronics (R&D) Ltd. * @@ -15,6 +15,8 @@ #include <linux/io.h> #include <linux/mutex.h> #include <linux/fs.h> +#include <linux/highmem.h> +#include <asm/pgtable.h> #include <asm/mmu_context.h> #include <asm/cacheflush.h> @@ -23,21 +25,12 @@ * flushing. Anything exceeding this will simply flush the dcache in its * entirety. */ -#define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */ #define MAX_ICACHE_PAGES 32 static void __flush_cache_4096(unsigned long addr, unsigned long phys, unsigned long exec_offset); /* - * This is initialised here to ensure that it is not placed in the BSS. If - * that were to happen, note that cache_init gets called before the BSS is - * cleared, so this would get nulled out which would be hopeless. - */ -static void (*__flush_dcache_segment_fn)(unsigned long, unsigned long) = - (void (*)(unsigned long, unsigned long))0xdeadbeef; - -/* * 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, @@ -95,16 +88,16 @@ static inline void flush_cache_4096(unsigned long start, unsigned long flags, exec_offset = 0; /* - * 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. + * All types of SH-4 require PC to be uncached to operate on the I-cache. + * Some types of SH-4 require PC to be uncached to operate on the D-cache. */ if ((boot_cpu_data.flags & CPU_HAS_P2_FLUSH_BUG) || (start < CACHE_OC_ADDRESS_ARRAY)) - exec_offset = 0x20000000; + exec_offset = cached_to_uncached; local_irq_save(flags); __flush_cache_4096(start | SH_CACHE_ASSOC, - P1SEGADDR(phys), exec_offset); + virt_to_phys(phys), exec_offset); local_irq_restore(flags); } @@ -123,12 +116,12 @@ static void sh4_flush_dcache_page(void *arg) else #endif { - unsigned long phys = PHYSADDR(page_address(page)); + unsigned long phys = page_to_phys(page); unsigned long addr = CACHE_OC_ADDRESS_ARRAY; int i, n; /* Loop all the D-cache */ - n = boot_cpu_data.dcache.n_aliases; + n = boot_cpu_data.dcache.way_incr >> 12; for (i = 0; i < n; i++, addr += 4096) flush_cache_4096(addr, phys); } @@ -158,10 +151,27 @@ static void __uses_jump_to_uncached flush_icache_all(void) local_irq_restore(flags); } -static inline void flush_dcache_all(void) +static void flush_dcache_all(void) { - (*__flush_dcache_segment_fn)(0UL, boot_cpu_data.dcache.way_size); - wmb(); + unsigned long addr, end_addr, entry_offset; + + end_addr = CACHE_OC_ADDRESS_ARRAY + + (current_cpu_data.dcache.sets << + current_cpu_data.dcache.entry_shift) * + current_cpu_data.dcache.ways; + + entry_offset = 1 << current_cpu_data.dcache.entry_shift; + + for (addr = CACHE_OC_ADDRESS_ARRAY; addr < end_addr; ) { + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + __raw_writel(0, addr); addr += entry_offset; + } } static void sh4_flush_cache_all(void *unused) @@ -170,89 +180,13 @@ static void sh4_flush_cache_all(void *unused) 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 = boot_cpu_data.dcache.alias_mask; - unsigned long n_aliases = boot_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. + * address (i.e. tag). It's no different here. * * Caller takes mm->mmap_sem. */ @@ -263,33 +197,7 @@ static void sh4_flush_cache_mm(void *arg) if (cpu_context(smp_processor_id(), mm) == NO_CONTEXT) return; - /* - * 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 (boot_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. - */ - 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(); + flush_dcache_all(); } /* @@ -302,44 +210,64 @@ static void sh4_flush_cache_page(void *args) { struct flusher_data *data = args; struct vm_area_struct *vma; + struct page *page; unsigned long address, pfn, phys; - unsigned int alias_mask; + int map_coherent = 0; + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + void *vaddr; vma = data->vma; address = data->addr1; pfn = data->addr2; phys = pfn << PAGE_SHIFT; + page = pfn_to_page(pfn); if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT) return; - alias_mask = boot_cpu_data.dcache.alias_mask; - - /* We only need to flush D-cache when we have alias */ - if ((address^phys) & alias_mask) { - /* Loop 4K of the D-cache */ - flush_cache_4096( - CACHE_OC_ADDRESS_ARRAY | (address & alias_mask), - phys); - /* Loop another 4K of the D-cache */ - flush_cache_4096( - CACHE_OC_ADDRESS_ARRAY | (phys & alias_mask), - phys); - } + address &= PAGE_MASK; + pgd = pgd_offset(vma->vm_mm, address); + pud = pud_offset(pgd, address); + pmd = pmd_offset(pud, address); + pte = pte_offset_kernel(pmd, address); + + /* If the page isn't present, there is nothing to do here. */ + if (!(pte_val(*pte) & _PAGE_PRESENT)) + return; - alias_mask = boot_cpu_data.icache.alias_mask; - if (vma->vm_flags & VM_EXEC) { + if ((vma->vm_mm == current->active_mm)) + vaddr = NULL; + else { /* - * Evict entries from the portion of the cache from which code - * may have been executed at this address (virtual). There's - * no need to evict from the portion corresponding to the - * physical address as for the D-cache, because we know the - * kernel has never executed the code through its identity - * translation. + * Use kmap_coherent or kmap_atomic to do flushes for + * another ASID than the current one. */ - flush_cache_4096( - CACHE_IC_ADDRESS_ARRAY | (address & alias_mask), - phys); + map_coherent = (current_cpu_data.dcache.n_aliases && + !test_bit(PG_dcache_dirty, &page->flags) && + page_mapped(page)); + if (map_coherent) + vaddr = kmap_coherent(page, address); + else + vaddr = kmap_atomic(page, KM_USER0); + + address = (unsigned long)vaddr; + } + + if (pages_do_alias(address, phys)) + flush_cache_4096(CACHE_OC_ADDRESS_ARRAY | + (address & shm_align_mask), phys); + + if (vma->vm_flags & VM_EXEC) + flush_icache_all(); + + if (vaddr) { + if (map_coherent) + kunmap_coherent(vaddr); + else + kunmap_atomic(vaddr, KM_USER0); } } @@ -372,24 +300,10 @@ static void sh4_flush_cache_range(void *args) if (boot_cpu_data.dcache.n_aliases == 0) return; - /* - * 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) >= MAX_DCACHE_PAGES) - flush_dcache_all(); - else - __flush_cache_mm(vma->vm_mm, start, end); + flush_dcache_all(); - if (vma->vm_flags & VM_EXEC) { - /* - * TODO: Is this required??? Need to look at how I-cache - * coherency is assured when new programs are loaded to see if - * this matters. - */ + if (vma->vm_flags & VM_EXEC) flush_icache_all(); - } } /** @@ -443,7 +357,7 @@ static void __flush_cache_4096(unsigned long addr, unsigned long phys, * pointless nead-of-loop check for 0 iterations. */ do { - ea = base_addr + PAGE_SIZE; + ea = base_addr + 4096; a = base_addr; p = phys; @@ -463,245 +377,6 @@ static void __flush_cache_4096(unsigned long addr, unsigned long phys, } while (--way_count != 0); } -/* - * Break the 1, 2 and 4 way variants of this out into separate functions to - * avoid nearly all the overhead of having the conditional stuff in the function - * bodies (+ the 1 and 2 way cases avoid saving any registers too). - * - * We want to eliminate unnecessary bus transactions, so this code uses - * a non-obvious technique. - * - * Loop over a cache way sized block of, one cache line at a time. For each - * line, use movca.a to cause the current cache line contents to be written - * back, but without reading anything from main memory. However this has the - * side effect that the cache is now caching that memory location. So follow - * this with a cache invalidate to mark the cache line invalid. And do all - * this with interrupts disabled, to avoid the cache line being accidently - * evicted while it is holding garbage. - * - * This also breaks in a number of circumstances: - * - if there are modifications to the region of memory just above - * empty_zero_page (for example because a breakpoint has been placed - * there), then these can be lost. - * - * This is because the the memory address which the cache temporarily - * caches in the above description is empty_zero_page. So the - * movca.l hits the cache (it is assumed that it misses, or at least - * isn't dirty), modifies the line and then invalidates it, losing the - * required change. - * - * - If caches are disabled or configured in write-through mode, then - * the movca.l writes garbage directly into memory. - */ -static void __flush_dcache_segment_writethrough(unsigned long start, - unsigned long extent_per_way) -{ - unsigned long addr; - int i; - - addr = CACHE_OC_ADDRESS_ARRAY | (start & cpu_data->dcache.entry_mask); - - while (extent_per_way) { - for (i = 0; i < cpu_data->dcache.ways; i++) - __raw_writel(0, addr + cpu_data->dcache.way_incr * i); - - addr += cpu_data->dcache.linesz; - extent_per_way -= cpu_data->dcache.linesz; - } -} - -static void __flush_dcache_segment_1way(unsigned long start, - unsigned long extent_per_way) -{ - unsigned long orig_sr, sr_with_bl; - unsigned long base_addr; - unsigned long way_incr, linesz, way_size; - struct cache_info *dcache; - register unsigned long a0, a0e; - - asm volatile("stc sr, %0" : "=r" (orig_sr)); - sr_with_bl = orig_sr | (1<<28); - base_addr = ((unsigned long)&empty_zero_page[0]); - - /* - * The previous code aligned base_addr to 16k, i.e. the way_size of all - * existing SH-4 D-caches. Whilst I don't see a need to have this - * aligned to any better than the cache line size (which it will be - * anyway by construction), let's align it to at least the way_size of - * any existing or conceivable SH-4 D-cache. -- RPC - */ - base_addr = ((base_addr >> 16) << 16); - base_addr |= start; - - dcache = &boot_cpu_data.dcache; - linesz = dcache->linesz; - way_incr = dcache->way_incr; - way_size = dcache->way_size; - - a0 = base_addr; - a0e = base_addr + extent_per_way; - do { - asm volatile("ldc %0, sr" : : "r" (sr_with_bl)); - asm volatile("movca.l r0, @%0\n\t" - "ocbi @%0" : : "r" (a0)); - a0 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "ocbi @%0" : : "r" (a0)); - a0 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "ocbi @%0" : : "r" (a0)); - a0 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "ocbi @%0" : : "r" (a0)); - asm volatile("ldc %0, sr" : : "r" (orig_sr)); - a0 += linesz; - } while (a0 < a0e); -} - -static void __flush_dcache_segment_2way(unsigned long start, - unsigned long extent_per_way) -{ - unsigned long orig_sr, sr_with_bl; - unsigned long base_addr; - unsigned long way_incr, linesz, way_size; - struct cache_info *dcache; - register unsigned long a0, a1, a0e; - - asm volatile("stc sr, %0" : "=r" (orig_sr)); - sr_with_bl = orig_sr | (1<<28); - base_addr = ((unsigned long)&empty_zero_page[0]); - - /* See comment under 1-way above */ - base_addr = ((base_addr >> 16) << 16); - base_addr |= start; - - dcache = &boot_cpu_data.dcache; - linesz = dcache->linesz; - way_incr = dcache->way_incr; - way_size = dcache->way_size; - - a0 = base_addr; - a1 = a0 + way_incr; - a0e = base_addr + extent_per_way; - do { - asm volatile("ldc %0, sr" : : "r" (sr_with_bl)); - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "ocbi @%0\n\t" - "ocbi @%1" : : - "r" (a0), "r" (a1)); - a0 += linesz; - a1 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "ocbi @%0\n\t" - "ocbi @%1" : : - "r" (a0), "r" (a1)); - a0 += linesz; - a1 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "ocbi @%0\n\t" - "ocbi @%1" : : - "r" (a0), "r" (a1)); - a0 += linesz; - a1 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "ocbi @%0\n\t" - "ocbi @%1" : : - "r" (a0), "r" (a1)); - asm volatile("ldc %0, sr" : : "r" (orig_sr)); - a0 += linesz; - a1 += linesz; - } while (a0 < a0e); -} - -static void __flush_dcache_segment_4way(unsigned long start, - unsigned long extent_per_way) -{ - unsigned long orig_sr, sr_with_bl; - unsigned long base_addr; - unsigned long way_incr, linesz, way_size; - struct cache_info *dcache; - register unsigned long a0, a1, a2, a3, a0e; - - asm volatile("stc sr, %0" : "=r" (orig_sr)); - sr_with_bl = orig_sr | (1<<28); - base_addr = ((unsigned long)&empty_zero_page[0]); - - /* See comment under 1-way above */ - base_addr = ((base_addr >> 16) << 16); - base_addr |= start; - - dcache = &boot_cpu_data.dcache; - linesz = dcache->linesz; - way_incr = dcache->way_incr; - way_size = dcache->way_size; - - a0 = base_addr; - a1 = a0 + way_incr; - a2 = a1 + way_incr; - a3 = a2 + way_incr; - a0e = base_addr + extent_per_way; - do { - asm volatile("ldc %0, sr" : : "r" (sr_with_bl)); - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "movca.l r0, @%2\n\t" - "movca.l r0, @%3\n\t" - "ocbi @%0\n\t" - "ocbi @%1\n\t" - "ocbi @%2\n\t" - "ocbi @%3\n\t" : : - "r" (a0), "r" (a1), "r" (a2), "r" (a3)); - a0 += linesz; - a1 += linesz; - a2 += linesz; - a3 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "movca.l r0, @%2\n\t" - "movca.l r0, @%3\n\t" - "ocbi @%0\n\t" - "ocbi @%1\n\t" - "ocbi @%2\n\t" - "ocbi @%3\n\t" : : - "r" (a0), "r" (a1), "r" (a2), "r" (a3)); - a0 += linesz; - a1 += linesz; - a2 += linesz; - a3 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "movca.l r0, @%2\n\t" - "movca.l r0, @%3\n\t" - "ocbi @%0\n\t" - "ocbi @%1\n\t" - "ocbi @%2\n\t" - "ocbi @%3\n\t" : : - "r" (a0), "r" (a1), "r" (a2), "r" (a3)); - a0 += linesz; - a1 += linesz; - a2 += linesz; - a3 += linesz; - asm volatile("movca.l r0, @%0\n\t" - "movca.l r0, @%1\n\t" - "movca.l r0, @%2\n\t" - "movca.l r0, @%3\n\t" - "ocbi @%0\n\t" - "ocbi @%1\n\t" - "ocbi @%2\n\t" - "ocbi @%3\n\t" : : - "r" (a0), "r" (a1), "r" (a2), "r" (a3)); - asm volatile("ldc %0, sr" : : "r" (orig_sr)); - a0 += linesz; - a1 += linesz; - a2 += linesz; - a3 += linesz; - } while (a0 < a0e); -} - extern void __weak sh4__flush_region_init(void); /* @@ -709,32 +384,11 @@ extern void __weak sh4__flush_region_init(void); */ void __init sh4_cache_init(void) { - unsigned int wt_enabled = !!(__raw_readl(CCR) & CCR_CACHE_WT); - printk("PVR=%08x CVR=%08x PRR=%08x\n", ctrl_inl(CCN_PVR), ctrl_inl(CCN_CVR), ctrl_inl(CCN_PRR)); - if (wt_enabled) - __flush_dcache_segment_fn = __flush_dcache_segment_writethrough; - else { - switch (boot_cpu_data.dcache.ways) { - case 1: - __flush_dcache_segment_fn = __flush_dcache_segment_1way; - break; - case 2: - __flush_dcache_segment_fn = __flush_dcache_segment_2way; - break; - case 4: - __flush_dcache_segment_fn = __flush_dcache_segment_4way; - break; - default: - panic("unknown number of cache ways\n"); - break; - } - } - local_flush_icache_range = sh4_flush_icache_range; local_flush_dcache_page = sh4_flush_dcache_page; local_flush_cache_all = sh4_flush_cache_all; |