Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright © 2008 Ingo Molnar |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 16 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. |
| 17 | */ |
| 18 | |
| 19 | #include <asm/iomap.h> |
Eric Anholt | ef5fa0a | 2009-01-23 14:14:21 -0800 | [diff] [blame] | 20 | #include <asm/pat.h> |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 21 | #include <linux/module.h> |
Akinobu Mita | 7ca43e7 | 2009-03-31 15:23:25 -0700 | [diff] [blame] | 22 | #include <linux/highmem.h> |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 23 | |
Venkatesh Pallipadi | 9e36fda | 2009-07-10 09:57:35 -0700 | [diff] [blame] | 24 | static int is_io_mapping_possible(resource_size_t base, unsigned long size) |
Venkatesh Pallipadi | 4ab0d47 | 2009-02-24 17:35:12 -0800 | [diff] [blame] | 25 | { |
Andrew Morton | 6a491e2 | 2009-04-02 16:44:38 -0700 | [diff] [blame] | 26 | #if !defined(CONFIG_X86_PAE) && defined(CONFIG_PHYS_ADDR_T_64BIT) |
Venkatesh Pallipadi | 4ab0d47 | 2009-02-24 17:35:12 -0800 | [diff] [blame] | 27 | /* There is no way to map greater than 1 << 32 address without PAE */ |
| 28 | if (base + size > 0x100000000ULL) |
| 29 | return 0; |
Ingo Molnar | 92b9af9 | 2009-02-28 14:09:27 +0100 | [diff] [blame] | 30 | #endif |
Venkatesh Pallipadi | 4ab0d47 | 2009-02-24 17:35:12 -0800 | [diff] [blame] | 31 | return 1; |
| 32 | } |
Venkatesh Pallipadi | 9e36fda | 2009-07-10 09:57:35 -0700 | [diff] [blame] | 33 | |
| 34 | int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot) |
| 35 | { |
| 36 | unsigned long flag = _PAGE_CACHE_WC; |
| 37 | int ret; |
| 38 | |
| 39 | if (!is_io_mapping_possible(base, size)) |
| 40 | return -EINVAL; |
| 41 | |
| 42 | ret = io_reserve_memtype(base, base + size, &flag); |
| 43 | if (ret) |
| 44 | return ret; |
| 45 | |
| 46 | *prot = __pgprot(__PAGE_KERNEL | flag); |
| 47 | return 0; |
| 48 | } |
| 49 | EXPORT_SYMBOL_GPL(iomap_create_wc); |
| 50 | |
| 51 | void |
| 52 | iomap_free(resource_size_t base, unsigned long size) |
| 53 | { |
| 54 | io_free_memtype(base, base + size); |
| 55 | } |
| 56 | EXPORT_SYMBOL_GPL(iomap_free); |
Venkatesh Pallipadi | 4ab0d47 | 2009-02-24 17:35:12 -0800 | [diff] [blame] | 57 | |
Ingo Molnar | dd63fdc | 2009-03-13 03:20:49 +0100 | [diff] [blame] | 58 | void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot) |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 59 | { |
| 60 | enum fixed_addresses idx; |
| 61 | unsigned long vaddr; |
| 62 | |
| 63 | pagefault_disable(); |
| 64 | |
Akinobu Mita | a7f8c50 | 2009-04-02 16:01:26 +0900 | [diff] [blame] | 65 | debug_kmap_atomic(type); |
Ingo Molnar | dd63fdc | 2009-03-13 03:20:49 +0100 | [diff] [blame] | 66 | idx = type + KM_TYPE_NR * smp_processor_id(); |
| 67 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); |
| 68 | set_pte(kmap_pte - idx, pfn_pte(pfn, prot)); |
| 69 | arch_flush_lazy_mmu_mode(); |
| 70 | |
| 71 | return (void *)vaddr; |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * Map 'pfn' using fixed map 'type' and protections 'prot' |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 76 | */ |
| 77 | void * |
| 78 | iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot) |
| 79 | { |
Eric Anholt | ef5fa0a | 2009-01-23 14:14:21 -0800 | [diff] [blame] | 80 | /* |
| 81 | * For non-PAT systems, promote PAGE_KERNEL_WC to PAGE_KERNEL_UC_MINUS. |
| 82 | * PAGE_KERNEL_WC maps to PWT, which translates to uncached if the |
| 83 | * MTRR is UC or WC. UC_MINUS gets the real intention, of the |
| 84 | * user, which is "WC if the MTRR is WC, UC if you can't do that." |
| 85 | */ |
| 86 | if (!pat_enabled && pgprot_val(prot) == pgprot_val(PAGE_KERNEL_WC)) |
| 87 | prot = PAGE_KERNEL_UC_MINUS; |
| 88 | |
Akinobu Mita | bb6d59c | 2009-03-11 23:33:18 +0900 | [diff] [blame] | 89 | return kmap_atomic_prot_pfn(pfn, type, prot); |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 90 | } |
| 91 | EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn); |
| 92 | |
| 93 | void |
| 94 | iounmap_atomic(void *kvaddr, enum km_type type) |
| 95 | { |
| 96 | unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; |
| 97 | enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); |
| 98 | |
| 99 | /* |
| 100 | * Force other mappings to Oops if they'll try to access this pte |
| 101 | * without first remap it. Keeping stale mappings around is a bad idea |
| 102 | * also, in case the page changes cacheability attributes or becomes |
| 103 | * a protected page in a hypervisor. |
| 104 | */ |
| 105 | if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) |
| 106 | kpte_clear_flush(kmap_pte-idx, vaddr); |
| 107 | |
Keith Packard | fd94093 | 2008-10-30 19:37:09 -0700 | [diff] [blame] | 108 | pagefault_enable(); |
| 109 | } |
| 110 | EXPORT_SYMBOL_GPL(iounmap_atomic); |