Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 1 | /* |
| 2 | * arch/sh/mm/kmap.c |
| 3 | * |
| 4 | * Copyright (C) 1999, 2000, 2002 Niibe Yutaka |
| 5 | * Copyright (C) 2002 - 2009 Paul Mundt |
| 6 | * |
| 7 | * Released under the terms of the GNU GPL v2.0. |
| 8 | */ |
| 9 | #include <linux/mm.h> |
| 10 | #include <linux/init.h> |
| 11 | #include <linux/mutex.h> |
| 12 | #include <linux/fs.h> |
| 13 | #include <linux/highmem.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <asm/mmu_context.h> |
| 16 | #include <asm/cacheflush.h> |
| 17 | |
| 18 | #define kmap_get_fixmap_pte(vaddr) \ |
| 19 | pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr)) |
| 20 | |
| 21 | static pte_t *kmap_coherent_pte; |
| 22 | |
| 23 | void __init kmap_coherent_init(void) |
| 24 | { |
| 25 | unsigned long vaddr; |
| 26 | |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 27 | /* cache the first coherent kmap pte */ |
| 28 | vaddr = __fix_to_virt(FIX_CMAP_BEGIN); |
| 29 | kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); |
| 30 | } |
| 31 | |
| 32 | void *kmap_coherent(struct page *page, unsigned long addr) |
| 33 | { |
| 34 | enum fixed_addresses idx; |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 35 | unsigned long vaddr; |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 36 | |
| 37 | BUG_ON(test_bit(PG_dcache_dirty, &page->flags)); |
| 38 | |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 39 | pagefault_disable(); |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 40 | |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 41 | idx = FIX_CMAP_END - |
| 42 | ((addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT); |
| 43 | vaddr = __fix_to_virt(idx); |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 44 | |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 45 | BUG_ON(!pte_none(*(kmap_coherent_pte - idx))); |
| 46 | set_pte(kmap_coherent_pte - idx, mk_pte(page, PAGE_KERNEL)); |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 47 | |
| 48 | return (void *)vaddr; |
| 49 | } |
| 50 | |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 51 | void kunmap_coherent(void *kvaddr) |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 52 | { |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 53 | if (kvaddr >= (void *)FIXADDR_START) { |
| 54 | unsigned long vaddr = (unsigned long)kvaddr & PAGE_MASK; |
| 55 | enum fixed_addresses idx = __virt_to_fix(vaddr); |
| 56 | |
Paul Mundt | 6e4154d | 2009-09-08 16:21:00 +0900 | [diff] [blame] | 57 | /* XXX.. Kill this later, here for sanity at the moment.. */ |
| 58 | __flush_purge_region((void *)vaddr, PAGE_SIZE); |
| 59 | |
Paul Mundt | 0906a3a | 2009-09-03 17:21:10 +0900 | [diff] [blame] | 60 | pte_clear(&init_mm, vaddr, kmap_coherent_pte - idx); |
| 61 | local_flush_tlb_one(get_asid(), vaddr); |
| 62 | } |
| 63 | |
| 64 | pagefault_enable(); |
Paul Mundt | 2739742 | 2009-08-15 09:19:19 +0900 | [diff] [blame] | 65 | } |