xref: /openbmc/linux/arch/nios2/mm/cacheflush.c (revision b38269ec)
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 #include <linux/pagemap.h>
15 
16 #include <asm/cacheflush.h>
17 #include <asm/cpuinfo.h>
18 
19 static void __flush_dcache(unsigned long start, unsigned long end)
20 {
21 	unsigned long addr;
22 
23 	start &= ~(cpuinfo.dcache_line_size - 1);
24 	end += (cpuinfo.dcache_line_size - 1);
25 	end &= ~(cpuinfo.dcache_line_size - 1);
26 
27 	if (end > start + cpuinfo.dcache_size)
28 		end = start + cpuinfo.dcache_size;
29 
30 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
31 		__asm__ __volatile__ ("   flushd 0(%0)\n"
32 					: /* Outputs */
33 					: /* Inputs  */ "r"(addr)
34 					/* : No clobber */);
35 	}
36 }
37 
38 static void __invalidate_dcache(unsigned long start, unsigned long end)
39 {
40 	unsigned long addr;
41 
42 	start &= ~(cpuinfo.dcache_line_size - 1);
43 	end += (cpuinfo.dcache_line_size - 1);
44 	end &= ~(cpuinfo.dcache_line_size - 1);
45 
46 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
47 		__asm__ __volatile__ ("   initda 0(%0)\n"
48 					: /* Outputs */
49 					: /* Inputs  */ "r"(addr)
50 					/* : No clobber */);
51 	}
52 }
53 
54 static void __flush_icache(unsigned long start, unsigned long end)
55 {
56 	unsigned long addr;
57 
58 	start &= ~(cpuinfo.icache_line_size - 1);
59 	end += (cpuinfo.icache_line_size - 1);
60 	end &= ~(cpuinfo.icache_line_size - 1);
61 
62 	if (end > start + cpuinfo.icache_size)
63 		end = start + cpuinfo.icache_size;
64 
65 	for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
66 		__asm__ __volatile__ ("   flushi %0\n"
67 					: /* Outputs */
68 					: /* Inputs  */ "r"(addr)
69 					/* : No clobber */);
70 	}
71 	__asm__ __volatile(" flushp\n");
72 }
73 
74 static void flush_aliases(struct address_space *mapping, struct page *page)
75 {
76 	struct mm_struct *mm = current->active_mm;
77 	struct vm_area_struct *mpnt;
78 	pgoff_t pgoff;
79 
80 	pgoff = page->index;
81 
82 	flush_dcache_mmap_lock(mapping);
83 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
84 		unsigned long offset;
85 
86 		if (mpnt->vm_mm != mm)
87 			continue;
88 		if (!(mpnt->vm_flags & VM_MAYSHARE))
89 			continue;
90 
91 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
92 		flush_cache_page(mpnt, mpnt->vm_start + offset,
93 			page_to_pfn(page));
94 	}
95 	flush_dcache_mmap_unlock(mapping);
96 }
97 
98 void flush_cache_all(void)
99 {
100 	__flush_dcache(0, cpuinfo.dcache_size);
101 	__flush_icache(0, cpuinfo.icache_size);
102 }
103 
104 void flush_cache_mm(struct mm_struct *mm)
105 {
106 	flush_cache_all();
107 }
108 
109 void flush_cache_dup_mm(struct mm_struct *mm)
110 {
111 	flush_cache_all();
112 }
113 
114 void flush_icache_range(unsigned long start, unsigned long end)
115 {
116 	__flush_dcache(start, end);
117 	__flush_icache(start, end);
118 }
119 
120 void flush_dcache_range(unsigned long start, unsigned long end)
121 {
122 	__flush_dcache(start, end);
123 	__flush_icache(start, end);
124 }
125 EXPORT_SYMBOL(flush_dcache_range);
126 
127 void invalidate_dcache_range(unsigned long start, unsigned long end)
128 {
129 	__invalidate_dcache(start, end);
130 }
131 EXPORT_SYMBOL(invalidate_dcache_range);
132 
133 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
134 			unsigned long end)
135 {
136 	__flush_dcache(start, end);
137 	if (vma == NULL || (vma->vm_flags & VM_EXEC))
138 		__flush_icache(start, end);
139 }
140 
141 void flush_icache_page(struct vm_area_struct *vma, struct page *page)
142 {
143 	unsigned long start = (unsigned long) page_address(page);
144 	unsigned long end = start + PAGE_SIZE;
145 
146 	__flush_dcache(start, end);
147 	__flush_icache(start, end);
148 }
149 
150 void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
151 			unsigned long pfn)
152 {
153 	unsigned long start = vmaddr;
154 	unsigned long end = start + PAGE_SIZE;
155 
156 	__flush_dcache(start, end);
157 	if (vma->vm_flags & VM_EXEC)
158 		__flush_icache(start, end);
159 }
160 
161 void __flush_dcache_page(struct address_space *mapping, struct page *page)
162 {
163 	/*
164 	 * Writeback any data associated with the kernel mapping of this
165 	 * page.  This ensures that data in the physical page is mutually
166 	 * coherent with the kernels mapping.
167 	 */
168 	unsigned long start = (unsigned long)page_address(page);
169 
170 	__flush_dcache(start, start + PAGE_SIZE);
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_file(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 		__flush_dcache_page(mapping, page);
191 		if (mapping) {
192 			unsigned long start = (unsigned long)page_address(page);
193 			flush_aliases(mapping,  page);
194 			flush_icache_range(start, start + PAGE_SIZE);
195 		}
196 		set_bit(PG_dcache_clean, &page->flags);
197 	}
198 }
199 EXPORT_SYMBOL(flush_dcache_page);
200 
201 void update_mmu_cache(struct vm_area_struct *vma,
202 		      unsigned long address, pte_t *ptep)
203 {
204 	pte_t pte = *ptep;
205 	unsigned long pfn = pte_pfn(pte);
206 	struct page *page;
207 	struct address_space *mapping;
208 
209 	reload_tlb_page(vma, address, pte);
210 
211 	if (!pfn_valid(pfn))
212 		return;
213 
214 	/*
215 	* The zero page is never written to, so never has any dirty
216 	* cache lines, and therefore never needs to be flushed.
217 	*/
218 	page = pfn_to_page(pfn);
219 	if (page == ZERO_PAGE(0))
220 		return;
221 
222 	mapping = page_mapping_file(page);
223 	if (!test_and_set_bit(PG_dcache_clean, &page->flags))
224 		__flush_dcache_page(mapping, page);
225 
226 	if(mapping)
227 	{
228 		flush_aliases(mapping, page);
229 		if (vma->vm_flags & VM_EXEC)
230 			flush_icache_page(vma, page);
231 	}
232 }
233 
234 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
235 		    struct page *to)
236 {
237 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
238 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
239 	copy_page(vto, vfrom);
240 	__flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
241 	__flush_icache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
242 }
243 
244 void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
245 {
246 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
247 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
248 	clear_page(addr);
249 	__flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
250 	__flush_icache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
251 }
252 
253 void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
254 			unsigned long user_vaddr,
255 			void *dst, void *src, int len)
256 {
257 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
258 	memcpy(dst, src, len);
259 	__flush_dcache((unsigned long)src, (unsigned long)src + len);
260 	if (vma->vm_flags & VM_EXEC)
261 		__flush_icache((unsigned long)src, (unsigned long)src + len);
262 }
263 
264 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
265 			unsigned long user_vaddr,
266 			void *dst, void *src, int len)
267 {
268 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
269 	memcpy(dst, src, len);
270 	__flush_dcache((unsigned long)dst, (unsigned long)dst + len);
271 	if (vma->vm_flags & VM_EXEC)
272 		__flush_icache((unsigned long)dst, (unsigned long)dst + len);
273 }
274