xref: /openbmc/linux/arch/mips/mm/cache.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/init.h>
12 #include <linux/kernel.h>
13 #include <linux/linkage.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/mm.h>
17 
18 #include <asm/cacheflush.h>
19 #include <asm/processor.h>
20 #include <asm/cpu.h>
21 #include <asm/cpu-features.h>
22 
23 /* Cache operations. */
24 void (*flush_cache_all)(void);
25 void (*__flush_cache_all)(void);
26 void (*flush_cache_mm)(struct mm_struct *mm);
27 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
28 	unsigned long end);
29 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
30 	unsigned long pfn);
31 void (*flush_icache_range)(unsigned long start, unsigned long end);
32 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
33 
34 void (*__flush_cache_vmap)(void);
35 void (*__flush_cache_vunmap)(void);
36 
37 /* MIPS specific cache operations */
38 void (*flush_cache_sigtramp)(unsigned long addr);
39 void (*local_flush_data_cache_page)(void * addr);
40 void (*flush_data_cache_page)(unsigned long addr);
41 void (*flush_icache_all)(void);
42 
43 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
44 EXPORT_SYMBOL(flush_data_cache_page);
45 
46 #ifdef CONFIG_DMA_NONCOHERENT
47 
48 /* DMA cache operations. */
49 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
50 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
51 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
52 
53 EXPORT_SYMBOL(_dma_cache_wback_inv);
54 
55 #endif /* CONFIG_DMA_NONCOHERENT */
56 
57 /*
58  * We could optimize the case where the cache argument is not BCACHE but
59  * that seems very atypical use ...
60  */
61 asmlinkage int sys_cacheflush(unsigned long addr,
62 	unsigned long bytes, unsigned int cache)
63 {
64 	if (bytes == 0)
65 		return 0;
66 	if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
67 		return -EFAULT;
68 
69 	flush_icache_range(addr, addr + bytes);
70 
71 	return 0;
72 }
73 
74 void __flush_dcache_page(struct page *page)
75 {
76 	struct address_space *mapping = page_mapping(page);
77 	unsigned long addr;
78 
79 	if (PageHighMem(page))
80 		return;
81 	if (mapping && !mapping_mapped(mapping)) {
82 		SetPageDcacheDirty(page);
83 		return;
84 	}
85 
86 	/*
87 	 * We could delay the flush for the !page_mapping case too.  But that
88 	 * case is for exec env/arg pages and those are %99 certainly going to
89 	 * get faulted into the tlb (and thus flushed) anyways.
90 	 */
91 	addr = (unsigned long) page_address(page);
92 	flush_data_cache_page(addr);
93 }
94 
95 EXPORT_SYMBOL(__flush_dcache_page);
96 
97 void __flush_anon_page(struct page *page, unsigned long vmaddr)
98 {
99 	unsigned long addr = (unsigned long) page_address(page);
100 
101 	if (pages_do_alias(addr, vmaddr)) {
102 		if (page_mapped(page) && !Page_dcache_dirty(page)) {
103 			void *kaddr;
104 
105 			kaddr = kmap_coherent(page, vmaddr);
106 			flush_data_cache_page((unsigned long)kaddr);
107 			kunmap_coherent();
108 		} else
109 			flush_data_cache_page(addr);
110 	}
111 }
112 
113 EXPORT_SYMBOL(__flush_anon_page);
114 
115 void __update_cache(struct vm_area_struct *vma, unsigned long address,
116 	pte_t pte)
117 {
118 	struct page *page;
119 	unsigned long pfn, addr;
120 	int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
121 
122 	pfn = pte_pfn(pte);
123 	if (unlikely(!pfn_valid(pfn)))
124 		return;
125 	page = pfn_to_page(pfn);
126 	if (page_mapping(page) && Page_dcache_dirty(page)) {
127 		addr = (unsigned long) page_address(page);
128 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
129 			flush_data_cache_page(addr);
130 		ClearPageDcacheDirty(page);
131 	}
132 }
133 
134 unsigned long _page_cachable_default;
135 EXPORT_SYMBOL_GPL(_page_cachable_default);
136 
137 static inline void setup_protection_map(void)
138 {
139 	protection_map[0] = PAGE_NONE;
140 	protection_map[1] = PAGE_READONLY;
141 	protection_map[2] = PAGE_COPY;
142 	protection_map[3] = PAGE_COPY;
143 	protection_map[4] = PAGE_READONLY;
144 	protection_map[5] = PAGE_READONLY;
145 	protection_map[6] = PAGE_COPY;
146 	protection_map[7] = PAGE_COPY;
147 	protection_map[8] = PAGE_NONE;
148 	protection_map[9] = PAGE_READONLY;
149 	protection_map[10] = PAGE_SHARED;
150 	protection_map[11] = PAGE_SHARED;
151 	protection_map[12] = PAGE_READONLY;
152 	protection_map[13] = PAGE_READONLY;
153 	protection_map[14] = PAGE_SHARED;
154 	protection_map[15] = PAGE_SHARED;
155 }
156 
157 void __devinit cpu_cache_init(void)
158 {
159 	if (cpu_has_3k_cache) {
160 		extern void __weak r3k_cache_init(void);
161 
162 		r3k_cache_init();
163 	}
164 	if (cpu_has_6k_cache) {
165 		extern void __weak r6k_cache_init(void);
166 
167 		r6k_cache_init();
168 	}
169 	if (cpu_has_4k_cache) {
170 		extern void __weak r4k_cache_init(void);
171 
172 		r4k_cache_init();
173 	}
174 	if (cpu_has_8k_cache) {
175 		extern void __weak r8k_cache_init(void);
176 
177 		r8k_cache_init();
178 	}
179 	if (cpu_has_tx39_cache) {
180 		extern void __weak tx39_cache_init(void);
181 
182 		tx39_cache_init();
183 	}
184 
185 	setup_protection_map();
186 }
187 
188 int __weak __uncached_access(struct file *file, unsigned long addr)
189 {
190 	if (file->f_flags & O_SYNC)
191 		return 1;
192 
193 	return addr >= __pa(high_memory);
194 }
195