xref: /openbmc/linux/arch/nios2/mm/cacheflush.c (revision 95777591)
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 	if (end > start + cpuinfo.dcache_size)
27 		end = start + cpuinfo.dcache_size;
28 
29 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
30 		__asm__ __volatile__ ("   flushd 0(%0)\n"
31 					: /* Outputs */
32 					: /* Inputs  */ "r"(addr)
33 					/* : No clobber */);
34 	}
35 }
36 
37 static void __invalidate_dcache(unsigned long start, unsigned long end)
38 {
39 	unsigned long addr;
40 
41 	start &= ~(cpuinfo.dcache_line_size - 1);
42 	end += (cpuinfo.dcache_line_size - 1);
43 	end &= ~(cpuinfo.dcache_line_size - 1);
44 
45 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
46 		__asm__ __volatile__ ("   initda 0(%0)\n"
47 					: /* Outputs */
48 					: /* Inputs  */ "r"(addr)
49 					/* : No clobber */);
50 	}
51 }
52 
53 static void __flush_icache(unsigned long start, unsigned long end)
54 {
55 	unsigned long addr;
56 
57 	start &= ~(cpuinfo.icache_line_size - 1);
58 	end += (cpuinfo.icache_line_size - 1);
59 	end &= ~(cpuinfo.icache_line_size - 1);
60 
61 	if (end > start + cpuinfo.icache_size)
62 		end = start + cpuinfo.icache_size;
63 
64 	for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
65 		__asm__ __volatile__ ("   flushi %0\n"
66 					: /* Outputs */
67 					: /* Inputs  */ "r"(addr)
68 					/* : No clobber */);
69 	}
70 	__asm__ __volatile(" flushp\n");
71 }
72 
73 static void flush_aliases(struct address_space *mapping, struct page *page)
74 {
75 	struct mm_struct *mm = current->active_mm;
76 	struct vm_area_struct *mpnt;
77 	pgoff_t pgoff;
78 
79 	pgoff = page->index;
80 
81 	flush_dcache_mmap_lock(mapping);
82 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
83 		unsigned long offset;
84 
85 		if (mpnt->vm_mm != mm)
86 			continue;
87 		if (!(mpnt->vm_flags & VM_MAYSHARE))
88 			continue;
89 
90 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
91 		flush_cache_page(mpnt, mpnt->vm_start + offset,
92 			page_to_pfn(page));
93 	}
94 	flush_dcache_mmap_unlock(mapping);
95 }
96 
97 void flush_cache_all(void)
98 {
99 	__flush_dcache(0, cpuinfo.dcache_size);
100 	__flush_icache(0, cpuinfo.icache_size);
101 }
102 
103 void flush_cache_mm(struct mm_struct *mm)
104 {
105 	flush_cache_all();
106 }
107 
108 void flush_cache_dup_mm(struct mm_struct *mm)
109 {
110 	flush_cache_all();
111 }
112 
113 void flush_icache_range(unsigned long start, unsigned long end)
114 {
115 	__flush_dcache(start, end);
116 	__flush_icache(start, end);
117 }
118 
119 void flush_dcache_range(unsigned long start, unsigned long end)
120 {
121 	__flush_dcache(start, end);
122 	__flush_icache(start, end);
123 }
124 EXPORT_SYMBOL(flush_dcache_range);
125 
126 void invalidate_dcache_range(unsigned long start, unsigned long end)
127 {
128 	__invalidate_dcache(start, end);
129 }
130 EXPORT_SYMBOL(invalidate_dcache_range);
131 
132 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
133 			unsigned long end)
134 {
135 	__flush_dcache(start, end);
136 	if (vma == NULL || (vma->vm_flags & VM_EXEC))
137 		__flush_icache(start, end);
138 }
139 
140 void flush_icache_page(struct vm_area_struct *vma, struct page *page)
141 {
142 	unsigned long start = (unsigned long) page_address(page);
143 	unsigned long end = start + PAGE_SIZE;
144 
145 	__flush_dcache(start, end);
146 	__flush_icache(start, end);
147 }
148 
149 void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
150 			unsigned long pfn)
151 {
152 	unsigned long start = vmaddr;
153 	unsigned long end = start + PAGE_SIZE;
154 
155 	__flush_dcache(start, end);
156 	if (vma->vm_flags & VM_EXEC)
157 		__flush_icache(start, end);
158 }
159 
160 void __flush_dcache_page(struct address_space *mapping, struct page *page)
161 {
162 	/*
163 	 * Writeback any data associated with the kernel mapping of this
164 	 * page.  This ensures that data in the physical page is mutually
165 	 * coherent with the kernels mapping.
166 	 */
167 	unsigned long start = (unsigned long)page_address(page);
168 
169 	__flush_dcache(start, start + PAGE_SIZE);
170 }
171 
172 void flush_dcache_page(struct page *page)
173 {
174 	struct address_space *mapping;
175 
176 	/*
177 	 * The zero page is never written to, so never has any dirty
178 	 * cache lines, and therefore never needs to be flushed.
179 	 */
180 	if (page == ZERO_PAGE(0))
181 		return;
182 
183 	mapping = page_mapping_file(page);
184 
185 	/* Flush this page if there are aliases. */
186 	if (mapping && !mapping_mapped(mapping)) {
187 		clear_bit(PG_dcache_clean, &page->flags);
188 	} else {
189 		__flush_dcache_page(mapping, page);
190 		if (mapping) {
191 			unsigned long start = (unsigned long)page_address(page);
192 			flush_aliases(mapping,  page);
193 			flush_icache_range(start, start + PAGE_SIZE);
194 		}
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 	struct address_space *mapping;
206 
207 	if (!pfn_valid(pfn))
208 		return;
209 
210 	/*
211 	* The zero page is never written to, so never has any dirty
212 	* cache lines, and therefore never needs to be flushed.
213 	*/
214 	page = pfn_to_page(pfn);
215 	if (page == ZERO_PAGE(0))
216 		return;
217 
218 	mapping = page_mapping_file(page);
219 	if (!test_and_set_bit(PG_dcache_clean, &page->flags))
220 		__flush_dcache_page(mapping, page);
221 
222 	if(mapping)
223 	{
224 		flush_aliases(mapping, page);
225 		if (vma->vm_flags & VM_EXEC)
226 			flush_icache_page(vma, 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 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
235 	copy_page(vto, vfrom);
236 	__flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
237 	__flush_icache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
238 }
239 
240 void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
241 {
242 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
243 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
244 	clear_page(addr);
245 	__flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
246 	__flush_icache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
247 }
248 
249 void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
250 			unsigned long user_vaddr,
251 			void *dst, void *src, int len)
252 {
253 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
254 	memcpy(dst, src, len);
255 	__flush_dcache((unsigned long)src, (unsigned long)src + len);
256 	if (vma->vm_flags & VM_EXEC)
257 		__flush_icache((unsigned long)src, (unsigned long)src + len);
258 }
259 
260 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
261 			unsigned long user_vaddr,
262 			void *dst, void *src, int len)
263 {
264 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
265 	memcpy(dst, src, len);
266 	__flush_dcache((unsigned long)dst, (unsigned long)dst + len);
267 	if (vma->vm_flags & VM_EXEC)
268 		__flush_icache((unsigned long)dst, (unsigned long)dst + len);
269 }
270