xref: /openbmc/linux/arch/mips/mm/cache.c (revision fd589a8f)
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/syscalls.h>
17 #include <linux/mm.h>
18 
19 #include <asm/cacheflush.h>
20 #include <asm/processor.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 
24 /* Cache operations. */
25 void (*flush_cache_all)(void);
26 void (*__flush_cache_all)(void);
27 void (*flush_cache_mm)(struct mm_struct *mm);
28 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
29 	unsigned long end);
30 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
31 	unsigned long pfn);
32 void (*flush_icache_range)(unsigned long start, unsigned long end);
33 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
34 
35 void (*__flush_cache_vmap)(void);
36 void (*__flush_cache_vunmap)(void);
37 
38 /* MIPS specific cache operations */
39 void (*flush_cache_sigtramp)(unsigned long addr);
40 void (*local_flush_data_cache_page)(void * addr);
41 void (*flush_data_cache_page)(unsigned long addr);
42 void (*flush_icache_all)(void);
43 
44 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
45 EXPORT_SYMBOL(flush_data_cache_page);
46 
47 #ifdef CONFIG_DMA_NONCOHERENT
48 
49 /* DMA cache operations. */
50 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
51 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
52 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
53 
54 EXPORT_SYMBOL(_dma_cache_wback_inv);
55 
56 #endif /* CONFIG_DMA_NONCOHERENT */
57 
58 /*
59  * We could optimize the case where the cache argument is not BCACHE but
60  * that seems very atypical use ...
61  */
62 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
63 	unsigned int, cache)
64 {
65 	if (bytes == 0)
66 		return 0;
67 	if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
68 		return -EFAULT;
69 
70 	flush_icache_range(addr, addr + bytes);
71 
72 	return 0;
73 }
74 
75 void __flush_dcache_page(struct page *page)
76 {
77 	struct address_space *mapping = page_mapping(page);
78 	unsigned long addr;
79 
80 	if (PageHighMem(page))
81 		return;
82 	if (mapping && !mapping_mapped(mapping)) {
83 		SetPageDcacheDirty(page);
84 		return;
85 	}
86 
87 	/*
88 	 * We could delay the flush for the !page_mapping case too.  But that
89 	 * case is for exec env/arg pages and those are %99 certainly going to
90 	 * get faulted into the tlb (and thus flushed) anyways.
91 	 */
92 	addr = (unsigned long) page_address(page);
93 	flush_data_cache_page(addr);
94 }
95 
96 EXPORT_SYMBOL(__flush_dcache_page);
97 
98 void __flush_anon_page(struct page *page, unsigned long vmaddr)
99 {
100 	unsigned long addr = (unsigned long) page_address(page);
101 
102 	if (pages_do_alias(addr, vmaddr)) {
103 		if (page_mapped(page) && !Page_dcache_dirty(page)) {
104 			void *kaddr;
105 
106 			kaddr = kmap_coherent(page, vmaddr);
107 			flush_data_cache_page((unsigned long)kaddr);
108 			kunmap_coherent();
109 		} else
110 			flush_data_cache_page(addr);
111 	}
112 }
113 
114 EXPORT_SYMBOL(__flush_anon_page);
115 
116 void __update_cache(struct vm_area_struct *vma, unsigned long address,
117 	pte_t pte)
118 {
119 	struct page *page;
120 	unsigned long pfn, addr;
121 	int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
122 
123 	pfn = pte_pfn(pte);
124 	if (unlikely(!pfn_valid(pfn)))
125 		return;
126 	page = pfn_to_page(pfn);
127 	if (page_mapping(page) && Page_dcache_dirty(page)) {
128 		addr = (unsigned long) page_address(page);
129 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
130 			flush_data_cache_page(addr);
131 		ClearPageDcacheDirty(page);
132 	}
133 }
134 
135 unsigned long _page_cachable_default;
136 EXPORT_SYMBOL_GPL(_page_cachable_default);
137 
138 static inline void setup_protection_map(void)
139 {
140 	protection_map[0] = PAGE_NONE;
141 	protection_map[1] = PAGE_READONLY;
142 	protection_map[2] = PAGE_COPY;
143 	protection_map[3] = PAGE_COPY;
144 	protection_map[4] = PAGE_READONLY;
145 	protection_map[5] = PAGE_READONLY;
146 	protection_map[6] = PAGE_COPY;
147 	protection_map[7] = PAGE_COPY;
148 	protection_map[8] = PAGE_NONE;
149 	protection_map[9] = PAGE_READONLY;
150 	protection_map[10] = PAGE_SHARED;
151 	protection_map[11] = PAGE_SHARED;
152 	protection_map[12] = PAGE_READONLY;
153 	protection_map[13] = PAGE_READONLY;
154 	protection_map[14] = PAGE_SHARED;
155 	protection_map[15] = PAGE_SHARED;
156 }
157 
158 void __devinit cpu_cache_init(void)
159 {
160 	if (cpu_has_3k_cache) {
161 		extern void __weak r3k_cache_init(void);
162 
163 		r3k_cache_init();
164 	}
165 	if (cpu_has_6k_cache) {
166 		extern void __weak r6k_cache_init(void);
167 
168 		r6k_cache_init();
169 	}
170 	if (cpu_has_4k_cache) {
171 		extern void __weak r4k_cache_init(void);
172 
173 		r4k_cache_init();
174 	}
175 	if (cpu_has_8k_cache) {
176 		extern void __weak r8k_cache_init(void);
177 
178 		r8k_cache_init();
179 	}
180 	if (cpu_has_tx39_cache) {
181 		extern void __weak tx39_cache_init(void);
182 
183 		tx39_cache_init();
184 	}
185 
186 	if (cpu_has_octeon_cache) {
187 		extern void __weak octeon_cache_init(void);
188 
189 		octeon_cache_init();
190 	}
191 
192 	setup_protection_map();
193 }
194 
195 int __weak __uncached_access(struct file *file, unsigned long addr)
196 {
197 	if (file->f_flags & O_SYNC)
198 		return 1;
199 
200 	return addr >= __pa(high_memory);
201 }
202