1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * linux/arch/unicore32/include/asm/cacheflush.h
4 *
5 * Code specific to PKUnity SoC and UniCore ISA
6 *
7 * Copyright (C) 2001-2010 GUAN Xue-tao
8 */
9 #ifndef __UNICORE_CACHEFLUSH_H__
10 #define __UNICORE_CACHEFLUSH_H__
11
12 #include <linux/mm.h>
13
14 #include <asm/shmparam.h>
15
16 #define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
17
18 /*
19 * This flag is used to indicate that the page pointed to by a pte is clean
20 * and does not require cleaning before returning it to the user.
21 */
22 #define PG_dcache_clean PG_arch_1
23
24 /*
25 * MM Cache Management
26 * ===================
27 *
28 * The arch/unicore32/mm/cache.S files implement these methods.
29 *
30 * Start addresses are inclusive and end addresses are exclusive;
31 * start addresses should be rounded down, end addresses up.
32 *
33 * See Documentation/core-api/cachetlb.rst for more information.
34 * Please note that the implementation of these, and the required
35 * effects are cache-type (VIVT/VIPT/PIPT) specific.
36 *
37 * flush_icache_all()
38 *
39 * Unconditionally clean and invalidate the entire icache.
40 * Currently only needed for cache-v6.S and cache-v7.S, see
41 * __flush_icache_all for the generic implementation.
42 *
43 * flush_kern_all()
44 *
45 * Unconditionally clean and invalidate the entire cache.
46 *
47 * flush_user_all()
48 *
49 * Clean and invalidate all user space cache entries
50 * before a change of page tables.
51 *
52 * flush_user_range(start, end, flags)
53 *
54 * Clean and invalidate a range of cache entries in the
55 * specified address space before a change of page tables.
56 * - start - user start address (inclusive, page aligned)
57 * - end - user end address (exclusive, page aligned)
58 * - flags - vma->vm_flags field
59 *
60 * coherent_kern_range(start, end)
61 *
62 * Ensure coherency between the Icache and the Dcache in the
63 * region described by start, end. If you have non-snooping
64 * Harvard caches, you need to implement this function.
65 * - start - virtual start address
66 * - end - virtual end address
67 *
68 * coherent_user_range(start, end)
69 *
70 * Ensure coherency between the Icache and the Dcache in the
71 * region described by start, end. If you have non-snooping
72 * Harvard caches, you need to implement this function.
73 * - start - virtual start address
74 * - end - virtual end address
75 *
76 * flush_kern_dcache_area(kaddr, size)
77 *
78 * Ensure that the data held in page is written back.
79 * - kaddr - page address
80 * - size - region size
81 *
82 * DMA Cache Coherency
83 * ===================
84 *
85 * dma_flush_range(start, end)
86 *
87 * Clean and invalidate the specified virtual address range.
88 * - start - virtual start address
89 * - end - virtual end address
90 */
91
92 extern void __cpuc_flush_icache_all(void);
93 extern void __cpuc_flush_kern_all(void);
94 extern void __cpuc_flush_user_all(void);
95 extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
96 extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
97 extern void __cpuc_coherent_user_range(unsigned long, unsigned long);
98 extern void __cpuc_flush_dcache_area(void *, size_t);
99 extern void __cpuc_flush_kern_dcache_area(void *addr, size_t size);
100
101 /*
102 * Copy user data from/to a page which is mapped into a different
103 * processes address space. Really, we want to allow our "user
104 * space" model to handle this.
105 */
106 extern void copy_to_user_page(struct vm_area_struct *, struct page *,
107 unsigned long, void *, const void *, unsigned long);
108 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
109 do { \
110 memcpy(dst, src, len); \
111 } while (0)
112
113 /*
114 * Convert calls to our calling convention.
115 */
116 /* Invalidate I-cache */
__flush_icache_all(void)117 static inline void __flush_icache_all(void)
118 {
119 asm("movc p0.c5, %0, #20;\n"
120 "nop; nop; nop; nop; nop; nop; nop; nop\n"
121 :
122 : "r" (0));
123 }
124
125 #define flush_cache_all() __cpuc_flush_kern_all()
126
127 extern void flush_cache_mm(struct mm_struct *mm);
128 extern void flush_cache_range(struct vm_area_struct *vma,
129 unsigned long start, unsigned long end);
130 extern void flush_cache_page(struct vm_area_struct *vma,
131 unsigned long user_addr, unsigned long pfn);
132
133 #define flush_cache_dup_mm(mm) flush_cache_mm(mm)
134
135 /*
136 * flush_cache_user_range is used when we want to ensure that the
137 * Harvard caches are synchronised for the user space address range.
138 * This is used for the UniCore private sys_cacheflush system call.
139 */
140 #define flush_cache_user_range(vma, start, end) \
141 __cpuc_coherent_user_range((start) & PAGE_MASK, PAGE_ALIGN(end))
142
143 /*
144 * Perform necessary cache operations to ensure that data previously
145 * stored within this range of addresses can be executed by the CPU.
146 */
147 #define flush_icache_range(s, e) __cpuc_coherent_kern_range(s, e)
148
149 /*
150 * Perform necessary cache operations to ensure that the TLB will
151 * see data written in the specified area.
152 */
153 #define clean_dcache_area(start, size) cpu_dcache_clean_area(start, size)
154
155 /*
156 * flush_dcache_page is used when the kernel has written to the page
157 * cache page at virtual address page->virtual.
158 *
159 * If this page isn't mapped (ie, page_mapping == NULL), or it might
160 * have userspace mappings, then we _must_ always clean + invalidate
161 * the dcache entries associated with the kernel mapping.
162 *
163 * Otherwise we can defer the operation, and clean the cache when we are
164 * about to change to user space. This is the same method as used on SPARC64.
165 * See update_mmu_cache for the user space part.
166 */
167 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
168 extern void flush_dcache_page(struct page *);
169
170 #define flush_dcache_mmap_lock(mapping) do { } while (0)
171 #define flush_dcache_mmap_unlock(mapping) do { } while (0)
172
173 #define flush_icache_user_range(vma, page, addr, len) \
174 flush_dcache_page(page)
175
176 /*
177 * We don't appear to need to do anything here. In fact, if we did, we'd
178 * duplicate cache flushing elsewhere performed by flush_dcache_page().
179 */
180 #define flush_icache_page(vma, page) do { } while (0)
181
182 /*
183 * flush_cache_vmap() is used when creating mappings (eg, via vmap,
184 * vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
185 * caches, since the direct-mappings of these pages may contain cached
186 * data, we need to do a full cache flush to ensure that writebacks
187 * don't corrupt data placed into these pages via the new mappings.
188 */
flush_cache_vmap(unsigned long start,unsigned long end)189 static inline void flush_cache_vmap(unsigned long start, unsigned long end)
190 {
191 }
192
flush_cache_vunmap(unsigned long start,unsigned long end)193 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
194 {
195 }
196
197 #endif
198