xref: /openbmc/linux/arch/mips/mm/cache.c (revision 0545810f)
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 #include <linux/pagemap.h>
19 
20 #include <asm/bcache.h>
21 #include <asm/cacheflush.h>
22 #include <asm/processor.h>
23 #include <asm/cpu.h>
24 #include <asm/cpu-features.h>
25 #include <asm/setup.h>
26 #include <asm/pgtable.h>
27 
28 /* Cache operations. */
29 void (*flush_cache_all)(void);
30 void (*__flush_cache_all)(void);
31 EXPORT_SYMBOL_GPL(__flush_cache_all);
32 void (*flush_cache_mm)(struct mm_struct *mm);
33 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
34 	unsigned long end);
35 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
36 	unsigned long pfn);
37 void (*flush_icache_range)(unsigned long start, unsigned long end);
38 EXPORT_SYMBOL_GPL(flush_icache_range);
39 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
40 EXPORT_SYMBOL_GPL(local_flush_icache_range);
41 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
42 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
43 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
44 
45 void (*__flush_cache_vmap)(void);
46 void (*__flush_cache_vunmap)(void);
47 
48 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
49 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
50 
51 /* MIPS specific cache operations */
52 void (*flush_data_cache_page)(unsigned long addr);
53 void (*flush_icache_all)(void);
54 
55 EXPORT_SYMBOL(flush_data_cache_page);
56 EXPORT_SYMBOL(flush_icache_all);
57 
58 /*
59  * Dummy cache handling routine
60  */
61 
62 void cache_noop(void) {}
63 
64 #ifdef CONFIG_BOARD_SCACHE
65 
66 static struct bcache_ops no_sc_ops = {
67 	.bc_enable = (void *)cache_noop,
68 	.bc_disable = (void *)cache_noop,
69 	.bc_wback_inv = (void *)cache_noop,
70 	.bc_inv = (void *)cache_noop
71 };
72 
73 struct bcache_ops *bcops = &no_sc_ops;
74 #endif
75 
76 #ifdef CONFIG_DMA_NONCOHERENT
77 
78 /* DMA cache operations. */
79 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
80 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
81 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
82 
83 #endif /* CONFIG_DMA_NONCOHERENT */
84 
85 /*
86  * We could optimize the case where the cache argument is not BCACHE but
87  * that seems very atypical use ...
88  */
89 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
90 	unsigned int, cache)
91 {
92 	if (bytes == 0)
93 		return 0;
94 	if (!access_ok((void __user *) addr, bytes))
95 		return -EFAULT;
96 
97 	__flush_icache_user_range(addr, addr + bytes);
98 
99 	return 0;
100 }
101 
102 void __flush_dcache_page(struct page *page)
103 {
104 	struct address_space *mapping = page_mapping_file(page);
105 	unsigned long addr;
106 
107 	if (mapping && !mapping_mapped(mapping)) {
108 		SetPageDcacheDirty(page);
109 		return;
110 	}
111 
112 	/*
113 	 * We could delay the flush for the !page_mapping case too.  But that
114 	 * case is for exec env/arg pages and those are %99 certainly going to
115 	 * get faulted into the tlb (and thus flushed) anyways.
116 	 */
117 	if (PageHighMem(page))
118 		addr = (unsigned long)kmap_atomic(page);
119 	else
120 		addr = (unsigned long)page_address(page);
121 
122 	flush_data_cache_page(addr);
123 
124 	if (PageHighMem(page))
125 		kunmap_atomic((void *)addr);
126 }
127 
128 EXPORT_SYMBOL(__flush_dcache_page);
129 
130 void __flush_anon_page(struct page *page, unsigned long vmaddr)
131 {
132 	unsigned long addr = (unsigned long) page_address(page);
133 
134 	if (pages_do_alias(addr, vmaddr)) {
135 		if (page_mapcount(page) && !Page_dcache_dirty(page)) {
136 			void *kaddr;
137 
138 			kaddr = kmap_coherent(page, vmaddr);
139 			flush_data_cache_page((unsigned long)kaddr);
140 			kunmap_coherent();
141 		} else
142 			flush_data_cache_page(addr);
143 	}
144 }
145 
146 EXPORT_SYMBOL(__flush_anon_page);
147 
148 void __update_cache(unsigned long address, pte_t pte)
149 {
150 	struct page *page;
151 	unsigned long pfn, addr;
152 	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
153 
154 	pfn = pte_pfn(pte);
155 	if (unlikely(!pfn_valid(pfn)))
156 		return;
157 	page = pfn_to_page(pfn);
158 	if (Page_dcache_dirty(page)) {
159 		if (PageHighMem(page))
160 			addr = (unsigned long)kmap_atomic(page);
161 		else
162 			addr = (unsigned long)page_address(page);
163 
164 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
165 			flush_data_cache_page(addr);
166 
167 		if (PageHighMem(page))
168 			kunmap_atomic((void *)addr);
169 
170 		ClearPageDcacheDirty(page);
171 	}
172 }
173 
174 unsigned long _page_cachable_default;
175 EXPORT_SYMBOL(_page_cachable_default);
176 
177 #define PM(p)	__pgprot(_page_cachable_default | (p))
178 
179 static pgprot_t protection_map[16] __ro_after_init;
180 DECLARE_VM_GET_PAGE_PROT
181 
182 static inline void setup_protection_map(void)
183 {
184 	protection_map[0]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
185 	protection_map[1]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
186 	protection_map[2]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
187 	protection_map[3]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
188 	protection_map[4]  = PM(_PAGE_PRESENT);
189 	protection_map[5]  = PM(_PAGE_PRESENT);
190 	protection_map[6]  = PM(_PAGE_PRESENT);
191 	protection_map[7]  = PM(_PAGE_PRESENT);
192 
193 	protection_map[8]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
194 	protection_map[9]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
195 	protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
196 				_PAGE_NO_READ);
197 	protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
198 	protection_map[12] = PM(_PAGE_PRESENT);
199 	protection_map[13] = PM(_PAGE_PRESENT);
200 	protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
201 	protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
202 }
203 
204 #undef PM
205 
206 void cpu_cache_init(void)
207 {
208 	if (cpu_has_3k_cache) {
209 		extern void __weak r3k_cache_init(void);
210 
211 		r3k_cache_init();
212 	}
213 	if (cpu_has_4k_cache) {
214 		extern void __weak r4k_cache_init(void);
215 
216 		r4k_cache_init();
217 	}
218 
219 	if (cpu_has_octeon_cache) {
220 		extern void __weak octeon_cache_init(void);
221 
222 		octeon_cache_init();
223 	}
224 
225 	setup_protection_map();
226 }
227