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/init.h>
12 #include <linux/kernel.h>
13 #include <linux/linkage.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/syscalls.h>
17 #include <linux/mm.h>
18 
19 #include <asm/cacheflush.h>
20 #include <asm/processor.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 
24 /* Cache operations. */
25 void (*flush_cache_all)(void);
26 void (*__flush_cache_all)(void);
27 void (*flush_cache_mm)(struct mm_struct *mm);
28 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
29 	unsigned long end);
30 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
31 	unsigned long pfn);
32 void (*flush_icache_range)(unsigned long start, unsigned long end);
33 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
34 
35 void (*__flush_cache_vmap)(void);
36 void (*__flush_cache_vunmap)(void);
37 
38 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
39 void (*__invalidate_kernel_vmap_range)(unsigned long vaddr, int size);
40 
41 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
42 
43 /* MIPS specific cache operations */
44 void (*flush_cache_sigtramp)(unsigned long addr);
45 void (*local_flush_data_cache_page)(void * addr);
46 void (*flush_data_cache_page)(unsigned long addr);
47 void (*flush_icache_all)(void);
48 
49 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
50 EXPORT_SYMBOL(flush_data_cache_page);
51 
52 #ifdef CONFIG_DMA_NONCOHERENT
53 
54 /* DMA cache operations. */
55 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
56 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
57 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
58 
59 EXPORT_SYMBOL(_dma_cache_wback_inv);
60 
61 #endif /* CONFIG_DMA_NONCOHERENT */
62 
63 /*
64  * We could optimize the case where the cache argument is not BCACHE but
65  * that seems very atypical use ...
66  */
SYSCALL_DEFINE3(cacheflush,unsigned long,addr,unsigned long,bytes,unsigned int,cache)67 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
68 	unsigned int, cache)
69 {
70 	if (bytes == 0)
71 		return 0;
72 	if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
73 		return -EFAULT;
74 
75 	flush_icache_range(addr, addr + bytes);
76 
77 	return 0;
78 }
79 
__flush_dcache_page(struct page * page)80 void __flush_dcache_page(struct page *page)
81 {
82 	struct address_space *mapping = page_mapping(page);
83 	unsigned long addr;
84 
85 	if (PageHighMem(page))
86 		return;
87 	if (mapping && !mapping_mapped(mapping)) {
88 		SetPageDcacheDirty(page);
89 		return;
90 	}
91 
92 	/*
93 	 * We could delay the flush for the !page_mapping case too.  But that
94 	 * case is for exec env/arg pages and those are %99 certainly going to
95 	 * get faulted into the tlb (and thus flushed) anyways.
96 	 */
97 	addr = (unsigned long) page_address(page);
98 	flush_data_cache_page(addr);
99 }
100 
101 EXPORT_SYMBOL(__flush_dcache_page);
102 
__flush_anon_page(struct page * page,unsigned long vmaddr)103 void __flush_anon_page(struct page *page, unsigned long vmaddr)
104 {
105 	unsigned long addr = (unsigned long) page_address(page);
106 
107 	if (pages_do_alias(addr, vmaddr)) {
108 		if (page_mapped(page) && !Page_dcache_dirty(page)) {
109 			void *kaddr;
110 
111 			kaddr = kmap_coherent(page, vmaddr);
112 			flush_data_cache_page((unsigned long)kaddr);
113 			kunmap_coherent();
114 		} else
115 			flush_data_cache_page(addr);
116 	}
117 }
118 
119 EXPORT_SYMBOL(__flush_anon_page);
120 
__update_cache(struct vm_area_struct * vma,unsigned long address,pte_t pte)121 void __update_cache(struct vm_area_struct *vma, unsigned long address,
122 	pte_t pte)
123 {
124 	struct page *page;
125 	unsigned long pfn, addr;
126 	int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
127 
128 	pfn = pte_pfn(pte);
129 	if (unlikely(!pfn_valid(pfn)))
130 		return;
131 	page = pfn_to_page(pfn);
132 	if (page_mapping(page) && Page_dcache_dirty(page)) {
133 		addr = (unsigned long) page_address(page);
134 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
135 			flush_data_cache_page(addr);
136 		ClearPageDcacheDirty(page);
137 	}
138 }
139 
140 unsigned long _page_cachable_default;
141 EXPORT_SYMBOL(_page_cachable_default);
142 
setup_protection_map(void)143 static inline void setup_protection_map(void)
144 {
145 	if (kernel_uses_smartmips_rixi) {
146 		protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
147 		protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
148 		protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
149 		protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
150 		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
151 		protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
152 		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
153 		protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
154 
155 		protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
156 		protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
157 		protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
158 		protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
159 		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
160 		protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
161 		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE  | _PAGE_NO_READ);
162 		protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
163 
164 	} else {
165 		protection_map[0] = PAGE_NONE;
166 		protection_map[1] = PAGE_READONLY;
167 		protection_map[2] = PAGE_COPY;
168 		protection_map[3] = PAGE_COPY;
169 		protection_map[4] = PAGE_READONLY;
170 		protection_map[5] = PAGE_READONLY;
171 		protection_map[6] = PAGE_COPY;
172 		protection_map[7] = PAGE_COPY;
173 		protection_map[8] = PAGE_NONE;
174 		protection_map[9] = PAGE_READONLY;
175 		protection_map[10] = PAGE_SHARED;
176 		protection_map[11] = PAGE_SHARED;
177 		protection_map[12] = PAGE_READONLY;
178 		protection_map[13] = PAGE_READONLY;
179 		protection_map[14] = PAGE_SHARED;
180 		protection_map[15] = PAGE_SHARED;
181 	}
182 }
183 
cpu_cache_init(void)184 void __cpuinit cpu_cache_init(void)
185 {
186 	if (cpu_has_3k_cache) {
187 		extern void __weak r3k_cache_init(void);
188 
189 		r3k_cache_init();
190 	}
191 	if (cpu_has_6k_cache) {
192 		extern void __weak r6k_cache_init(void);
193 
194 		r6k_cache_init();
195 	}
196 	if (cpu_has_4k_cache) {
197 		extern void __weak r4k_cache_init(void);
198 
199 		r4k_cache_init();
200 	}
201 	if (cpu_has_8k_cache) {
202 		extern void __weak r8k_cache_init(void);
203 
204 		r8k_cache_init();
205 	}
206 	if (cpu_has_tx39_cache) {
207 		extern void __weak tx39_cache_init(void);
208 
209 		tx39_cache_init();
210 	}
211 
212 	if (cpu_has_octeon_cache) {
213 		extern void __weak octeon_cache_init(void);
214 
215 		octeon_cache_init();
216 	}
217 
218 	setup_protection_map();
219 }
220 
__uncached_access(struct file * file,unsigned long addr)221 int __weak __uncached_access(struct file *file, unsigned long addr)
222 {
223 	if (file->f_flags & O_DSYNC)
224 		return 1;
225 
226 	return addr >= __pa(high_memory);
227 }
228