xref: /openbmc/linux/arch/mips/mm/cache.c (revision fb574682)
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 
19 #include <asm/cacheflush.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 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
40 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
41 
42 void (*__flush_cache_vmap)(void);
43 void (*__flush_cache_vunmap)(void);
44 
45 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
46 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
47 
48 /* MIPS specific cache operations */
49 void (*local_flush_data_cache_page)(void * addr);
50 void (*flush_data_cache_page)(unsigned long addr);
51 void (*flush_icache_all)(void);
52 
53 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
54 EXPORT_SYMBOL(flush_data_cache_page);
55 EXPORT_SYMBOL(flush_icache_all);
56 
57 #ifdef CONFIG_DMA_NONCOHERENT
58 
59 /* DMA cache operations. */
60 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
61 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
62 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
63 
64 #endif /* CONFIG_DMA_NONCOHERENT */
65 
66 /*
67  * We could optimize the case where the cache argument is not BCACHE but
68  * that seems very atypical use ...
69  */
70 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
71 	unsigned int, cache)
72 {
73 	if (bytes == 0)
74 		return 0;
75 	if (!access_ok((void __user *) addr, bytes))
76 		return -EFAULT;
77 
78 	__flush_icache_user_range(addr, addr + bytes);
79 
80 	return 0;
81 }
82 
83 void __flush_dcache_page(struct page *page)
84 {
85 	struct address_space *mapping = page_mapping_file(page);
86 	unsigned long addr;
87 
88 	if (mapping && !mapping_mapped(mapping)) {
89 		SetPageDcacheDirty(page);
90 		return;
91 	}
92 
93 	/*
94 	 * We could delay the flush for the !page_mapping case too.  But that
95 	 * case is for exec env/arg pages and those are %99 certainly going to
96 	 * get faulted into the tlb (and thus flushed) anyways.
97 	 */
98 	if (PageHighMem(page))
99 		addr = (unsigned long)kmap_atomic(page);
100 	else
101 		addr = (unsigned long)page_address(page);
102 
103 	flush_data_cache_page(addr);
104 
105 	if (PageHighMem(page))
106 		kunmap_atomic((void *)addr);
107 }
108 
109 EXPORT_SYMBOL(__flush_dcache_page);
110 
111 void __flush_anon_page(struct page *page, unsigned long vmaddr)
112 {
113 	unsigned long addr = (unsigned long) page_address(page);
114 
115 	if (pages_do_alias(addr, vmaddr)) {
116 		if (page_mapcount(page) && !Page_dcache_dirty(page)) {
117 			void *kaddr;
118 
119 			kaddr = kmap_coherent(page, vmaddr);
120 			flush_data_cache_page((unsigned long)kaddr);
121 			kunmap_coherent();
122 		} else
123 			flush_data_cache_page(addr);
124 	}
125 }
126 
127 EXPORT_SYMBOL(__flush_anon_page);
128 
129 void __update_cache(unsigned long address, pte_t pte)
130 {
131 	struct page *page;
132 	unsigned long pfn, addr;
133 	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
134 
135 	pfn = pte_pfn(pte);
136 	if (unlikely(!pfn_valid(pfn)))
137 		return;
138 	page = pfn_to_page(pfn);
139 	if (Page_dcache_dirty(page)) {
140 		if (PageHighMem(page))
141 			addr = (unsigned long)kmap_atomic(page);
142 		else
143 			addr = (unsigned long)page_address(page);
144 
145 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
146 			flush_data_cache_page(addr);
147 
148 		if (PageHighMem(page))
149 			kunmap_atomic((void *)addr);
150 
151 		ClearPageDcacheDirty(page);
152 	}
153 }
154 
155 unsigned long _page_cachable_default;
156 EXPORT_SYMBOL(_page_cachable_default);
157 
158 static inline void setup_protection_map(void)
159 {
160 	if (cpu_has_rixi) {
161 		protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
162 		protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
163 		protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
164 		protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
165 		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
166 		protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
167 		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
168 		protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
169 
170 		protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
171 		protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
172 		protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
173 		protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
174 		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
175 		protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
176 		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
177 		protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
178 
179 	} else {
180 		protection_map[0] = PAGE_NONE;
181 		protection_map[1] = PAGE_READONLY;
182 		protection_map[2] = PAGE_COPY;
183 		protection_map[3] = PAGE_COPY;
184 		protection_map[4] = PAGE_READONLY;
185 		protection_map[5] = PAGE_READONLY;
186 		protection_map[6] = PAGE_COPY;
187 		protection_map[7] = PAGE_COPY;
188 		protection_map[8] = PAGE_NONE;
189 		protection_map[9] = PAGE_READONLY;
190 		protection_map[10] = PAGE_SHARED;
191 		protection_map[11] = PAGE_SHARED;
192 		protection_map[12] = PAGE_READONLY;
193 		protection_map[13] = PAGE_READONLY;
194 		protection_map[14] = PAGE_SHARED;
195 		protection_map[15] = PAGE_SHARED;
196 	}
197 }
198 
199 void cpu_cache_init(void)
200 {
201 	if (cpu_has_3k_cache) {
202 		extern void __weak r3k_cache_init(void);
203 
204 		r3k_cache_init();
205 	}
206 	if (cpu_has_6k_cache) {
207 		extern void __weak r6k_cache_init(void);
208 
209 		r6k_cache_init();
210 	}
211 	if (cpu_has_4k_cache) {
212 		extern void __weak r4k_cache_init(void);
213 
214 		r4k_cache_init();
215 	}
216 	if (cpu_has_8k_cache) {
217 		extern void __weak r8k_cache_init(void);
218 
219 		r8k_cache_init();
220 	}
221 	if (cpu_has_tx39_cache) {
222 		extern void __weak tx39_cache_init(void);
223 
224 		tx39_cache_init();
225 	}
226 
227 	if (cpu_has_octeon_cache) {
228 		extern void __weak octeon_cache_init(void);
229 
230 		octeon_cache_init();
231 	}
232 
233 	setup_protection_map();
234 }
235 
236 int __weak __uncached_access(struct file *file, unsigned long addr)
237 {
238 	if (file->f_flags & O_DSYNC)
239 		return 1;
240 
241 	return addr >= __pa(high_memory);
242 }
243