xref: /linux/arch/nios2/mm/cacheflush.c (revision 2009337e30cdae64405ea7b8fa1578b921508871)
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) 2009, Wind River Systems Inc
7  * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
8  */
9 
10 #include <linux/export.h>
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <linux/fs.h>
14 
15 #include <asm/cacheflush.h>
16 #include <asm/cpuinfo.h>
17 
18 static void __flush_dcache(unsigned long start, unsigned long end)
19 {
20 	unsigned long addr;
21 
22 	start &= ~(cpuinfo.dcache_line_size - 1);
23 	end += (cpuinfo.dcache_line_size - 1);
24 	end &= ~(cpuinfo.dcache_line_size - 1);
25 
26 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
27 		__asm__ __volatile__ ("   flushda 0(%0)\n"
28 					: /* Outputs */
29 					: /* Inputs  */ "r"(addr)
30 					/* : No clobber */);
31 	}
32 }
33 
34 static void __flush_dcache_all(unsigned long start, unsigned long end)
35 {
36 	unsigned long addr;
37 
38 	start &= ~(cpuinfo.dcache_line_size - 1);
39 	end += (cpuinfo.dcache_line_size - 1);
40 	end &= ~(cpuinfo.dcache_line_size - 1);
41 
42 	if (end > start + cpuinfo.dcache_size)
43 		end = start + cpuinfo.dcache_size;
44 
45 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
46 		__asm__ __volatile__ ("   flushd 0(%0)\n"
47 					: /* Outputs */
48 					: /* Inputs  */ "r"(addr)
49 					/* : No clobber */);
50 	}
51 }
52 
53 static void __invalidate_dcache(unsigned long start, unsigned long end)
54 {
55 	unsigned long addr;
56 
57 	start &= ~(cpuinfo.dcache_line_size - 1);
58 	end += (cpuinfo.dcache_line_size - 1);
59 	end &= ~(cpuinfo.dcache_line_size - 1);
60 
61 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
62 		__asm__ __volatile__ ("   initda 0(%0)\n"
63 					: /* Outputs */
64 					: /* Inputs  */ "r"(addr)
65 					/* : No clobber */);
66 	}
67 }
68 
69 static void __flush_icache(unsigned long start, unsigned long end)
70 {
71 	unsigned long addr;
72 
73 	start &= ~(cpuinfo.icache_line_size - 1);
74 	end += (cpuinfo.icache_line_size - 1);
75 	end &= ~(cpuinfo.icache_line_size - 1);
76 
77 	if (end > start + cpuinfo.icache_size)
78 		end = start + cpuinfo.icache_size;
79 
80 	for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
81 		__asm__ __volatile__ ("   flushi %0\n"
82 					: /* Outputs */
83 					: /* Inputs  */ "r"(addr)
84 					/* : No clobber */);
85 	}
86 	__asm__ __volatile(" flushp\n");
87 }
88 
89 static void flush_aliases(struct address_space *mapping, struct page *page)
90 {
91 	struct mm_struct *mm = current->active_mm;
92 	struct vm_area_struct *mpnt;
93 	pgoff_t pgoff;
94 
95 	pgoff = page->index;
96 
97 	flush_dcache_mmap_lock(mapping);
98 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
99 		unsigned long offset;
100 
101 		if (mpnt->vm_mm != mm)
102 			continue;
103 		if (!(mpnt->vm_flags & VM_MAYSHARE))
104 			continue;
105 
106 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
107 		flush_cache_page(mpnt, mpnt->vm_start + offset,
108 			page_to_pfn(page));
109 	}
110 	flush_dcache_mmap_unlock(mapping);
111 }
112 
113 void flush_cache_all(void)
114 {
115 	__flush_dcache_all(0, cpuinfo.dcache_size);
116 	__flush_icache(0, cpuinfo.icache_size);
117 }
118 
119 void flush_cache_mm(struct mm_struct *mm)
120 {
121 	flush_cache_all();
122 }
123 
124 void flush_cache_dup_mm(struct mm_struct *mm)
125 {
126 	flush_cache_all();
127 }
128 
129 void flush_icache_range(unsigned long start, unsigned long end)
130 {
131 	__flush_icache(start, end);
132 }
133 
134 void flush_dcache_range(unsigned long start, unsigned long end)
135 {
136 	__flush_dcache(start, end);
137 }
138 EXPORT_SYMBOL(flush_dcache_range);
139 
140 void invalidate_dcache_range(unsigned long start, unsigned long end)
141 {
142 	__invalidate_dcache(start, end);
143 }
144 EXPORT_SYMBOL(invalidate_dcache_range);
145 
146 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
147 			unsigned long end)
148 {
149 	__flush_dcache(start, end);
150 	if (vma == NULL || (vma->vm_flags & VM_EXEC))
151 		__flush_icache(start, end);
152 }
153 
154 void flush_icache_page(struct vm_area_struct *vma, struct page *page)
155 {
156 	unsigned long start = (unsigned long) page_address(page);
157 	unsigned long end = start + PAGE_SIZE;
158 
159 	__flush_icache(start, end);
160 }
161 
162 void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
163 			unsigned long pfn)
164 {
165 	unsigned long start = vmaddr;
166 	unsigned long end = start + PAGE_SIZE;
167 
168 	__flush_dcache(start, end);
169 	if (vma->vm_flags & VM_EXEC)
170 		__flush_icache(start, end);
171 }
172 
173 void flush_dcache_page(struct page *page)
174 {
175 	struct address_space *mapping;
176 
177 	/*
178 	 * The zero page is never written to, so never has any dirty
179 	 * cache lines, and therefore never needs to be flushed.
180 	 */
181 	if (page == ZERO_PAGE(0))
182 		return;
183 
184 	mapping = page_mapping(page);
185 
186 	/* Flush this page if there are aliases. */
187 	if (mapping && !mapping_mapped(mapping)) {
188 		clear_bit(PG_dcache_clean, &page->flags);
189 	} else {
190 		unsigned long start = (unsigned long)page_address(page);
191 
192 		__flush_dcache_all(start, start + PAGE_SIZE);
193 		if (mapping)
194 			flush_aliases(mapping,  page);
195 		set_bit(PG_dcache_clean, &page->flags);
196 	}
197 }
198 EXPORT_SYMBOL(flush_dcache_page);
199 
200 void update_mmu_cache(struct vm_area_struct *vma,
201 		      unsigned long address, pte_t *pte)
202 {
203 	unsigned long pfn = pte_pfn(*pte);
204 	struct page *page;
205 
206 	if (!pfn_valid(pfn))
207 		return;
208 
209 	/*
210 	* The zero page is never written to, so never has any dirty
211 	* cache lines, and therefore never needs to be flushed.
212 	*/
213 	page = pfn_to_page(pfn);
214 	if (page == ZERO_PAGE(0))
215 		return;
216 
217 	if (!PageReserved(page) &&
218 	     !test_and_set_bit(PG_dcache_clean, &page->flags)) {
219 		unsigned long start = page_to_virt(page);
220 		struct address_space *mapping;
221 
222 		__flush_dcache(start, start + PAGE_SIZE);
223 
224 		mapping = page_mapping(page);
225 		if (mapping)
226 			flush_aliases(mapping, page);
227 	}
228 }
229 
230 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
231 		    struct page *to)
232 {
233 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
234 	copy_page(vto, vfrom);
235 	__flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
236 }
237 
238 void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
239 {
240 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
241 	clear_page(addr);
242 	__flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
243 }
244 
245 void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
246 			unsigned long user_vaddr,
247 			void *dst, void *src, int len)
248 {
249 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
250 	memcpy(dst, src, len);
251 	__flush_dcache((unsigned long)src, (unsigned long)src + len);
252 	if (vma->vm_flags & VM_EXEC)
253 		__flush_icache((unsigned long)src, (unsigned long)src + len);
254 }
255 
256 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
257 			unsigned long user_vaddr,
258 			void *dst, void *src, int len)
259 {
260 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
261 	memcpy(dst, src, len);
262 	__flush_dcache((unsigned long)dst, (unsigned long)dst + len);
263 	if (vma->vm_flags & VM_EXEC)
264 		__flush_icache((unsigned long)dst, (unsigned long)dst + len);
265 }
266