xref: /openbmc/linux/arch/mips/mm/cache.c (revision cfdfc14e)
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 (*flush_cache_sigtramp)(unsigned long addr);
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 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
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 EXPORT_SYMBOL(_dma_cache_wback_inv);
67 
68 #endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
69 
70 /*
71  * We could optimize the case where the cache argument is not BCACHE but
72  * that seems very atypical use ...
73  */
74 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
75 	unsigned int, cache)
76 {
77 	if (bytes == 0)
78 		return 0;
79 	if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
80 		return -EFAULT;
81 
82 	__flush_icache_user_range(addr, addr + bytes);
83 
84 	return 0;
85 }
86 
87 void __flush_dcache_page(struct page *page)
88 {
89 	struct address_space *mapping = page_mapping_file(page);
90 	unsigned long addr;
91 
92 	if (mapping && !mapping_mapped(mapping)) {
93 		SetPageDcacheDirty(page);
94 		return;
95 	}
96 
97 	/*
98 	 * We could delay the flush for the !page_mapping case too.  But that
99 	 * case is for exec env/arg pages and those are %99 certainly going to
100 	 * get faulted into the tlb (and thus flushed) anyways.
101 	 */
102 	if (PageHighMem(page))
103 		addr = (unsigned long)kmap_atomic(page);
104 	else
105 		addr = (unsigned long)page_address(page);
106 
107 	flush_data_cache_page(addr);
108 
109 	if (PageHighMem(page))
110 		__kunmap_atomic((void *)addr);
111 }
112 
113 EXPORT_SYMBOL(__flush_dcache_page);
114 
115 void __flush_anon_page(struct page *page, unsigned long vmaddr)
116 {
117 	unsigned long addr = (unsigned long) page_address(page);
118 
119 	if (pages_do_alias(addr, vmaddr)) {
120 		if (page_mapcount(page) && !Page_dcache_dirty(page)) {
121 			void *kaddr;
122 
123 			kaddr = kmap_coherent(page, vmaddr);
124 			flush_data_cache_page((unsigned long)kaddr);
125 			kunmap_coherent();
126 		} else
127 			flush_data_cache_page(addr);
128 	}
129 }
130 
131 EXPORT_SYMBOL(__flush_anon_page);
132 
133 void __update_cache(unsigned long address, pte_t pte)
134 {
135 	struct page *page;
136 	unsigned long pfn, addr;
137 	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
138 
139 	pfn = pte_pfn(pte);
140 	if (unlikely(!pfn_valid(pfn)))
141 		return;
142 	page = pfn_to_page(pfn);
143 	if (Page_dcache_dirty(page)) {
144 		if (PageHighMem(page))
145 			addr = (unsigned long)kmap_atomic(page);
146 		else
147 			addr = (unsigned long)page_address(page);
148 
149 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
150 			flush_data_cache_page(addr);
151 
152 		if (PageHighMem(page))
153 			__kunmap_atomic((void *)addr);
154 
155 		ClearPageDcacheDirty(page);
156 	}
157 }
158 
159 unsigned long _page_cachable_default;
160 EXPORT_SYMBOL(_page_cachable_default);
161 
162 static inline void setup_protection_map(void)
163 {
164 	if (cpu_has_rixi) {
165 		protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
166 		protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
167 		protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
168 		protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
169 		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
170 		protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
171 		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
172 		protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
173 
174 		protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
175 		protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
176 		protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
177 		protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
178 		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
179 		protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
180 		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
181 		protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
182 
183 	} else {
184 		protection_map[0] = PAGE_NONE;
185 		protection_map[1] = PAGE_READONLY;
186 		protection_map[2] = PAGE_COPY;
187 		protection_map[3] = PAGE_COPY;
188 		protection_map[4] = PAGE_READONLY;
189 		protection_map[5] = PAGE_READONLY;
190 		protection_map[6] = PAGE_COPY;
191 		protection_map[7] = PAGE_COPY;
192 		protection_map[8] = PAGE_NONE;
193 		protection_map[9] = PAGE_READONLY;
194 		protection_map[10] = PAGE_SHARED;
195 		protection_map[11] = PAGE_SHARED;
196 		protection_map[12] = PAGE_READONLY;
197 		protection_map[13] = PAGE_READONLY;
198 		protection_map[14] = PAGE_SHARED;
199 		protection_map[15] = PAGE_SHARED;
200 	}
201 }
202 
203 void cpu_cache_init(void)
204 {
205 	if (cpu_has_3k_cache) {
206 		extern void __weak r3k_cache_init(void);
207 
208 		r3k_cache_init();
209 	}
210 	if (cpu_has_6k_cache) {
211 		extern void __weak r6k_cache_init(void);
212 
213 		r6k_cache_init();
214 	}
215 	if (cpu_has_4k_cache) {
216 		extern void __weak r4k_cache_init(void);
217 
218 		r4k_cache_init();
219 	}
220 	if (cpu_has_8k_cache) {
221 		extern void __weak r8k_cache_init(void);
222 
223 		r8k_cache_init();
224 	}
225 	if (cpu_has_tx39_cache) {
226 		extern void __weak tx39_cache_init(void);
227 
228 		tx39_cache_init();
229 	}
230 
231 	if (cpu_has_octeon_cache) {
232 		extern void __weak octeon_cache_init(void);
233 
234 		octeon_cache_init();
235 	}
236 
237 	setup_protection_map();
238 }
239 
240 int __weak __uncached_access(struct file *file, unsigned long addr)
241 {
242 	if (file->f_flags & O_DSYNC)
243 		return 1;
244 
245 	return addr >= __pa(high_memory);
246 }
247