1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994 - 2003, 06, 07 by Ralf Baechle (ralf@linux-mips.org)
7  * Copyright (C) 2007 MIPS Technologies, Inc.
8  */
9 #include <linux/fs.h>
10 #include <linux/fcntl.h>
11 #include <linux/kernel.h>
12 #include <linux/linkage.h>
13 #include <linux/export.h>
14 #include <linux/sched.h>
15 #include <linux/syscalls.h>
16 #include <linux/mm.h>
17 #include <linux/highmem.h>
18 #include <linux/pagemap.h>
19 
20 #include <asm/cacheflush.h>
21 #include <asm/processor.h>
22 #include <asm/cpu.h>
23 #include <asm/cpu-features.h>
24 #include <asm/setup.h>
25 #include <asm/pgtable.h>
26 
27 /* Cache operations. */
28 void (*flush_cache_all)(void);
29 void (*__flush_cache_all)(void);
30 EXPORT_SYMBOL_GPL(__flush_cache_all);
31 void (*flush_cache_mm)(struct mm_struct *mm);
32 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
33 	unsigned long end);
34 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
35 	unsigned long pfn);
36 void (*flush_icache_range)(unsigned long start, unsigned long end);
37 EXPORT_SYMBOL_GPL(flush_icache_range);
38 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
39 EXPORT_SYMBOL_GPL(local_flush_icache_range);
40 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
41 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
42 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
43 
44 void (*__flush_cache_vmap)(void);
45 void (*__flush_cache_vunmap)(void);
46 
47 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
48 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
49 
50 /* MIPS specific cache operations */
51 void (*local_flush_data_cache_page)(void * addr);
52 void (*flush_data_cache_page)(unsigned long addr);
53 void (*flush_icache_all)(void);
54 
55 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
56 EXPORT_SYMBOL(flush_data_cache_page);
57 EXPORT_SYMBOL(flush_icache_all);
58 
59 #ifdef CONFIG_DMA_NONCOHERENT
60 
61 /* DMA cache operations. */
62 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
63 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
64 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
65 
66 #endif /* CONFIG_DMA_NONCOHERENT */
67 
68 /*
69  * We could optimize the case where the cache argument is not BCACHE but
70  * that seems very atypical use ...
71  */
SYSCALL_DEFINE3(cacheflush,unsigned long,addr,unsigned long,bytes,unsigned int,cache)72 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
73 	unsigned int, cache)
74 {
75 	if (bytes == 0)
76 		return 0;
77 	if (!access_ok((void __user *) addr, bytes))
78 		return -EFAULT;
79 
80 	__flush_icache_user_range(addr, addr + bytes);
81 
82 	return 0;
83 }
84 
__flush_dcache_page(struct page * page)85 void __flush_dcache_page(struct page *page)
86 {
87 	struct address_space *mapping = page_mapping_file(page);
88 	unsigned long addr;
89 
90 	if (mapping && !mapping_mapped(mapping)) {
91 		SetPageDcacheDirty(page);
92 		return;
93 	}
94 
95 	/*
96 	 * We could delay the flush for the !page_mapping case too.  But that
97 	 * case is for exec env/arg pages and those are %99 certainly going to
98 	 * get faulted into the tlb (and thus flushed) anyways.
99 	 */
100 	if (PageHighMem(page))
101 		addr = (unsigned long)kmap_atomic(page);
102 	else
103 		addr = (unsigned long)page_address(page);
104 
105 	flush_data_cache_page(addr);
106 
107 	if (PageHighMem(page))
108 		kunmap_atomic((void *)addr);
109 }
110 
111 EXPORT_SYMBOL(__flush_dcache_page);
112 
__flush_anon_page(struct page * page,unsigned long vmaddr)113 void __flush_anon_page(struct page *page, unsigned long vmaddr)
114 {
115 	unsigned long addr = (unsigned long) page_address(page);
116 
117 	if (pages_do_alias(addr, vmaddr)) {
118 		if (page_mapcount(page) && !Page_dcache_dirty(page)) {
119 			void *kaddr;
120 
121 			kaddr = kmap_coherent(page, vmaddr);
122 			flush_data_cache_page((unsigned long)kaddr);
123 			kunmap_coherent();
124 		} else
125 			flush_data_cache_page(addr);
126 	}
127 }
128 
129 EXPORT_SYMBOL(__flush_anon_page);
130 
__update_cache(unsigned long address,pte_t pte)131 void __update_cache(unsigned long address, pte_t pte)
132 {
133 	struct page *page;
134 	unsigned long pfn, addr;
135 	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
136 
137 	pfn = pte_pfn(pte);
138 	if (unlikely(!pfn_valid(pfn)))
139 		return;
140 	page = pfn_to_page(pfn);
141 	if (Page_dcache_dirty(page)) {
142 		if (PageHighMem(page))
143 			addr = (unsigned long)kmap_atomic(page);
144 		else
145 			addr = (unsigned long)page_address(page);
146 
147 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
148 			flush_data_cache_page(addr);
149 
150 		if (PageHighMem(page))
151 			kunmap_atomic((void *)addr);
152 
153 		ClearPageDcacheDirty(page);
154 	}
155 }
156 
157 unsigned long _page_cachable_default;
158 EXPORT_SYMBOL(_page_cachable_default);
159 
160 #define PM(p)	__pgprot(_page_cachable_default | (p))
161 
setup_protection_map(void)162 static inline void setup_protection_map(void)
163 {
164 	protection_map[0]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
165 	protection_map[1]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
166 	protection_map[2]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
167 	protection_map[3]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
168 	protection_map[4]  = PM(_PAGE_PRESENT);
169 	protection_map[5]  = PM(_PAGE_PRESENT);
170 	protection_map[6]  = PM(_PAGE_PRESENT);
171 	protection_map[7]  = PM(_PAGE_PRESENT);
172 
173 	protection_map[8]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
174 	protection_map[9]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
175 	protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
176 				_PAGE_NO_READ);
177 	protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
178 	protection_map[12] = PM(_PAGE_PRESENT);
179 	protection_map[13] = PM(_PAGE_PRESENT);
180 	protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
181 	protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
182 }
183 
184 #undef PM
185 
cpu_cache_init(void)186 void cpu_cache_init(void)
187 {
188 	if (cpu_has_3k_cache) {
189 		extern void __weak r3k_cache_init(void);
190 
191 		r3k_cache_init();
192 	}
193 	if (cpu_has_4k_cache) {
194 		extern void __weak r4k_cache_init(void);
195 
196 		r4k_cache_init();
197 	}
198 	if (cpu_has_tx39_cache) {
199 		extern void __weak tx39_cache_init(void);
200 
201 		tx39_cache_init();
202 	}
203 
204 	if (cpu_has_octeon_cache) {
205 		extern void __weak octeon_cache_init(void);
206 
207 		octeon_cache_init();
208 	}
209 
210 	setup_protection_map();
211 }
212