xref: /openbmc/linux/arch/mips/mm/cache.c (revision 78beef62)
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 
18 #include <asm/cacheflush.h>
19 #include <asm/highmem.h>
20 #include <asm/processor.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 #include <asm/setup.h>
24 
25 /* Cache operations. */
26 void (*flush_cache_all)(void);
27 void (*__flush_cache_all)(void);
28 EXPORT_SYMBOL_GPL(__flush_cache_all);
29 void (*flush_cache_mm)(struct mm_struct *mm);
30 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
31 	unsigned long end);
32 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
33 	unsigned long pfn);
34 void (*flush_icache_range)(unsigned long start, unsigned long end);
35 EXPORT_SYMBOL_GPL(flush_icache_range);
36 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
37 EXPORT_SYMBOL_GPL(local_flush_icache_range);
38 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
39 EXPORT_SYMBOL_GPL(__flush_icache_user_range);
40 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
41 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
42 
43 void (*__flush_cache_vmap)(void);
44 void (*__flush_cache_vunmap)(void);
45 
46 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
47 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
48 
49 /* MIPS specific cache operations */
50 void (*local_flush_data_cache_page)(void * addr);
51 void (*flush_data_cache_page)(unsigned long addr);
52 void (*flush_icache_all)(void);
53 
54 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
55 EXPORT_SYMBOL(flush_data_cache_page);
56 EXPORT_SYMBOL(flush_icache_all);
57 
58 #ifdef CONFIG_DMA_NONCOHERENT
59 
60 /* DMA cache operations. */
61 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
62 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
63 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
64 
65 #endif /* CONFIG_DMA_NONCOHERENT */
66 
67 /*
68  * We could optimize the case where the cache argument is not BCACHE but
69  * that seems very atypical use ...
70  */
71 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
72 	unsigned int, cache)
73 {
74 	if (bytes == 0)
75 		return 0;
76 	if (!access_ok((void __user *) addr, bytes))
77 		return -EFAULT;
78 
79 	__flush_icache_user_range(addr, addr + bytes);
80 
81 	return 0;
82 }
83 
84 void __flush_dcache_page(struct page *page)
85 {
86 	struct address_space *mapping = page_mapping_file(page);
87 	unsigned long addr;
88 
89 	if (mapping && !mapping_mapped(mapping)) {
90 		SetPageDcacheDirty(page);
91 		return;
92 	}
93 
94 	/*
95 	 * We could delay the flush for the !page_mapping case too.  But that
96 	 * case is for exec env/arg pages and those are %99 certainly going to
97 	 * get faulted into the tlb (and thus flushed) anyways.
98 	 */
99 	if (PageHighMem(page))
100 		addr = (unsigned long)kmap_atomic(page);
101 	else
102 		addr = (unsigned long)page_address(page);
103 
104 	flush_data_cache_page(addr);
105 
106 	if (PageHighMem(page))
107 		__kunmap_atomic((void *)addr);
108 }
109 
110 EXPORT_SYMBOL(__flush_dcache_page);
111 
112 void __flush_anon_page(struct page *page, unsigned long vmaddr)
113 {
114 	unsigned long addr = (unsigned long) page_address(page);
115 
116 	if (pages_do_alias(addr, vmaddr)) {
117 		if (page_mapcount(page) && !Page_dcache_dirty(page)) {
118 			void *kaddr;
119 
120 			kaddr = kmap_coherent(page, vmaddr);
121 			flush_data_cache_page((unsigned long)kaddr);
122 			kunmap_coherent();
123 		} else
124 			flush_data_cache_page(addr);
125 	}
126 }
127 
128 EXPORT_SYMBOL(__flush_anon_page);
129 
130 void __update_cache(unsigned long address, pte_t pte)
131 {
132 	struct page *page;
133 	unsigned long pfn, addr;
134 	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
135 
136 	pfn = pte_pfn(pte);
137 	if (unlikely(!pfn_valid(pfn)))
138 		return;
139 	page = pfn_to_page(pfn);
140 	if (Page_dcache_dirty(page)) {
141 		if (PageHighMem(page))
142 			addr = (unsigned long)kmap_atomic(page);
143 		else
144 			addr = (unsigned long)page_address(page);
145 
146 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
147 			flush_data_cache_page(addr);
148 
149 		if (PageHighMem(page))
150 			__kunmap_atomic((void *)addr);
151 
152 		ClearPageDcacheDirty(page);
153 	}
154 }
155 
156 unsigned long _page_cachable_default;
157 EXPORT_SYMBOL(_page_cachable_default);
158 
159 static inline void setup_protection_map(void)
160 {
161 	if (cpu_has_rixi) {
162 		protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
163 		protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
164 		protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
165 		protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
166 		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
167 		protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
168 		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
169 		protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
170 
171 		protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
172 		protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
173 		protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
174 		protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
175 		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
176 		protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
177 		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
178 		protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
179 
180 	} else {
181 		protection_map[0] = PAGE_NONE;
182 		protection_map[1] = PAGE_READONLY;
183 		protection_map[2] = PAGE_COPY;
184 		protection_map[3] = PAGE_COPY;
185 		protection_map[4] = PAGE_READONLY;
186 		protection_map[5] = PAGE_READONLY;
187 		protection_map[6] = PAGE_COPY;
188 		protection_map[7] = PAGE_COPY;
189 		protection_map[8] = PAGE_NONE;
190 		protection_map[9] = PAGE_READONLY;
191 		protection_map[10] = PAGE_SHARED;
192 		protection_map[11] = PAGE_SHARED;
193 		protection_map[12] = PAGE_READONLY;
194 		protection_map[13] = PAGE_READONLY;
195 		protection_map[14] = PAGE_SHARED;
196 		protection_map[15] = PAGE_SHARED;
197 	}
198 }
199 
200 void cpu_cache_init(void)
201 {
202 	if (cpu_has_3k_cache) {
203 		extern void __weak r3k_cache_init(void);
204 
205 		r3k_cache_init();
206 	}
207 	if (cpu_has_6k_cache) {
208 		extern void __weak r6k_cache_init(void);
209 
210 		r6k_cache_init();
211 	}
212 	if (cpu_has_4k_cache) {
213 		extern void __weak r4k_cache_init(void);
214 
215 		r4k_cache_init();
216 	}
217 	if (cpu_has_8k_cache) {
218 		extern void __weak r8k_cache_init(void);
219 
220 		r8k_cache_init();
221 	}
222 	if (cpu_has_tx39_cache) {
223 		extern void __weak tx39_cache_init(void);
224 
225 		tx39_cache_init();
226 	}
227 
228 	if (cpu_has_octeon_cache) {
229 		extern void __weak octeon_cache_init(void);
230 
231 		octeon_cache_init();
232 	}
233 
234 	setup_protection_map();
235 }
236 
237 int __weak __uncached_access(struct file *file, unsigned long addr)
238 {
239 	if (file->f_flags & O_DSYNC)
240 		return 1;
241 
242 	return addr >= __pa(high_memory);
243 }
244