| /* |
| * arch/sh/mm/cache-sh4.c |
| * |
| * Copyright (C) 1999, 2000, 2002 Niibe Yutaka |
| * Copyright (C) 2001 - 2009 Paul Mundt |
| * Copyright (C) 2003 Richard Curnow |
| * Copyright (c) 2007 STMicroelectronics (R&D) Ltd. |
| * |
| * 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/mm.h> |
| #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> |
| |
| /* |
| * 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_ICACHE_PAGES 32 |
| |
| static void __flush_cache_one(unsigned long addr, unsigned long phys, |
| unsigned long exec_offset); |
| |
| /* |
| * 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, |
| * signal handler code and kprobes code |
| */ |
| static void __uses_jump_to_uncached sh4_flush_icache_range(void *args) |
| { |
| struct flusher_data *data = args; |
| unsigned long start, end; |
| unsigned long flags, v; |
| int i; |
| |
| start = data->addr1; |
| end = data->addr2; |
| |
| /* If there are too many pages then just blow away the caches */ |
| if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) { |
| local_flush_cache_all(NULL); |
| return; |
| } |
| |
| /* |
| * Selectively flush d-cache then invalidate the i-cache. |
| * This is inefficient, so only use this for small ranges. |
| */ |
| start &= ~(L1_CACHE_BYTES-1); |
| end += L1_CACHE_BYTES-1; |
| end &= ~(L1_CACHE_BYTES-1); |
| |
| local_irq_save(flags); |
| jump_to_uncached(); |
| |
| for (v = start; v < end; v += L1_CACHE_BYTES) { |
| unsigned long icacheaddr; |
| int j, n; |
| |
| __ocbwb(v); |
| |
| icacheaddr = CACHE_IC_ADDRESS_ARRAY | (v & |
| cpu_data->icache.entry_mask); |
| |
| /* Clear i-cache line valid-bit */ |
| n = boot_cpu_data.icache.n_aliases; |
| for (i = 0; i < cpu_data->icache.ways; i++) { |
| for (j = 0; j < n; j++) |
| __raw_writel(0, icacheaddr + (j * PAGE_SIZE)); |
| icacheaddr += cpu_data->icache.way_incr; |
| } |
| } |
| |
| back_to_cached(); |
| local_irq_restore(flags); |
| } |
| |
| static inline void flush_cache_one(unsigned long start, unsigned long phys) |
| { |
| unsigned long flags, exec_offset = 0; |
| |
| /* |
| * 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 = cached_to_uncached; |
| |
| local_irq_save(flags); |
| __flush_cache_one(start, phys, exec_offset); |
| local_irq_restore(flags); |
| } |
| |
| /* |
| * Write back & invalidate the D-cache of the page. |
| * (To avoid "alias" issues) |
| */ |
| static void sh4_flush_dcache_page(void *arg) |
| { |
| struct page *page = arg; |
| #ifndef CONFIG_SMP |
| struct address_space *mapping = page_mapping(page); |
| |
| if (mapping && !mapping_mapped(mapping)) |
| set_bit(PG_dcache_dirty, &page->flags); |
| else |
| #endif |
| { |
| 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; |
| for (i = 0; i < n; i++, addr += PAGE_SIZE) |
| flush_cache_one(addr, phys); |
| } |
| |
| wmb(); |
| } |
| |
| /* TODO: Selective icache invalidation through IC address array.. */ |
| static void __uses_jump_to_uncached flush_icache_all(void) |
| { |
| unsigned long flags, ccr; |
| |
| local_irq_save(flags); |
| jump_to_uncached(); |
| |
| /* Flush I-cache */ |
| ccr = ctrl_inl(CCR); |
| ccr |= CCR_CACHE_ICI; |
| ctrl_outl(ccr, CCR); |
| |
| /* |
| * back_to_cached() will take care of the barrier for us, don't add |
| * another one! |
| */ |
| |
| back_to_cached(); |
| local_irq_restore(flags); |
| } |
| |
| static void flush_dcache_all(void) |
| { |
| 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) |
| { |
| flush_dcache_all(); |
| flush_icache_all(); |
| } |
| |
| /* |
| * 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. |
| * |
| * Caller takes mm->mmap_sem. |
| */ |
| static void sh4_flush_cache_mm(void *arg) |
| { |
| struct mm_struct *mm = arg; |
| |
| if (cpu_context(smp_processor_id(), mm) == NO_CONTEXT) |
| return; |
| |
| flush_dcache_all(); |
| } |
| |
| /* |
| * Write back and invalidate I/D-caches for the page. |
| * |
| * ADDR: Virtual Address (U0 address) |
| * PFN: Physical page number |
| */ |
| 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; |
| int map_coherent = 0; |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte; |
| void *vaddr; |
| |
| vma = data->vma; |
| address = data->addr1 & PAGE_MASK; |
| pfn = data->addr2; |
| phys = pfn << PAGE_SHIFT; |
| page = pfn_to_page(pfn); |
| |
| if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT) |
| return; |
| |
| 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; |
| |
| if ((vma->vm_mm == current->active_mm)) |
| vaddr = NULL; |
| else { |
| /* |
| * Use kmap_coherent or kmap_atomic to do flushes for |
| * another ASID than the current one. |
| */ |
| 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; |
| } |
| |
| flush_cache_one(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); |
| } |
| } |
| |
| /* |
| * 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. |
| */ |
| static void sh4_flush_cache_range(void *args) |
| { |
| struct flusher_data *data = args; |
| struct vm_area_struct *vma; |
| unsigned long start, end; |
| |
| vma = data->vma; |
| start = data->addr1; |
| end = data->addr2; |
| |
| if (cpu_context(smp_processor_id(), vma->vm_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; |
| |
| flush_dcache_all(); |
| |
| if (vma->vm_flags & VM_EXEC) |
| flush_icache_all(); |
| } |
| |
| /** |
| * __flush_cache_one |
| * |
| * @addr: address in memory mapped cache array |
| * @phys: P1 address to flush (has to match tags if addr has 'A' bit |
| * set i.e. associative write) |
| * @exec_offset: set to 0x20000000 if flush has to be executed from P2 |
| * region else 0x0 |
| * |
| * The offset into the cache array implied by 'addr' selects the |
| * 'colour' of the virtual address range that will be flushed. The |
| * operation (purge/write-back) is selected by the lower 2 bits of |
| * 'phys'. |
| */ |
| static void __flush_cache_one(unsigned long addr, unsigned long phys, |
| unsigned long exec_offset) |
| { |
| int way_count; |
| unsigned long base_addr = addr; |
| struct cache_info *dcache; |
| unsigned long way_incr; |
| unsigned long a, ea, p; |
| unsigned long temp_pc; |
| |
| dcache = &boot_cpu_data.dcache; |
| /* Write this way for better assembly. */ |
| way_count = dcache->ways; |
| way_incr = dcache->way_incr; |
| |
| /* |
| * Apply exec_offset (i.e. branch to P2 if required.). |
| * |
| * FIXME: |
| * |
| * If I write "=r" for the (temp_pc), it puts this in r6 hence |
| * trashing exec_offset before it's been added on - why? Hence |
| * "=&r" as a 'workaround' |
| */ |
| asm volatile("mov.l 1f, %0\n\t" |
| "add %1, %0\n\t" |
| "jmp @%0\n\t" |
| "nop\n\t" |
| ".balign 4\n\t" |
| "1: .long 2f\n\t" |
| "2:\n" : "=&r" (temp_pc) : "r" (exec_offset)); |
| |
| /* |
| * We know there will be >=1 iteration, so write as do-while to avoid |
| * pointless nead-of-loop check for 0 iterations. |
| */ |
| do { |
| ea = base_addr + PAGE_SIZE; |
| a = base_addr; |
| p = phys; |
| |
| do { |
| *(volatile unsigned long *)a = p; |
| /* |
| * Next line: intentionally not p+32, saves an add, p |
| * will do since only the cache tag bits need to |
| * match. |
| */ |
| *(volatile unsigned long *)(a+32) = p; |
| a += 64; |
| p += 64; |
| } while (a < ea); |
| |
| base_addr += way_incr; |
| } while (--way_count != 0); |
| } |
| |
| extern void __weak sh4__flush_region_init(void); |
| |
| /* |
| * SH-4 has virtually indexed and physically tagged cache. |
| */ |
| void __init sh4_cache_init(void) |
| { |
| printk("PVR=%08x CVR=%08x PRR=%08x\n", |
| ctrl_inl(CCN_PVR), |
| ctrl_inl(CCN_CVR), |
| ctrl_inl(CCN_PRR)); |
| |
| local_flush_icache_range = sh4_flush_icache_range; |
| local_flush_dcache_page = sh4_flush_dcache_page; |
| local_flush_cache_all = sh4_flush_cache_all; |
| local_flush_cache_mm = sh4_flush_cache_mm; |
| local_flush_cache_dup_mm = sh4_flush_cache_mm; |
| local_flush_cache_page = sh4_flush_cache_page; |
| local_flush_cache_range = sh4_flush_cache_range; |
| |
| sh4__flush_region_init(); |
| } |