1 /*
2  * Copyright 2010 Tilera Corporation. All Rights Reserved.
3  *
4  *   This program is free software; you can redistribute it and/or
5  *   modify it under the terms of the GNU General Public License
6  *   as published by the Free Software Foundation, version 2.
7  *
8  *   This program is distributed in the hope that it will be useful, but
9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11  *   NON INFRINGEMENT.  See the GNU General Public License for
12  *   more details.
13  */
14 
15 #ifndef _ASM_TILE_CACHEFLUSH_H
16 #define _ASM_TILE_CACHEFLUSH_H
17 
18 #include <arch/chip.h>
19 
20 /* Keep includes the same across arches.  */
21 #include <linux/mm.h>
22 #include <linux/cache.h>
23 #include <arch/icache.h>
24 
25 /* Caches are physically-indexed and so don't need special treatment */
26 #define flush_cache_all()			do { } while (0)
27 #define flush_cache_mm(mm)			do { } while (0)
28 #define flush_cache_dup_mm(mm)			do { } while (0)
29 #define flush_cache_range(vma, start, end)	do { } while (0)
30 #define flush_cache_page(vma, vmaddr, pfn)	do { } while (0)
31 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
32 #define flush_dcache_page(page)			do { } while (0)
33 #define flush_dcache_mmap_lock(mapping)		do { } while (0)
34 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)
35 #define flush_cache_vmap(start, end)		do { } while (0)
36 #define flush_cache_vunmap(start, end)		do { } while (0)
37 #define flush_icache_page(vma, pg)		do { } while (0)
38 #define flush_icache_user_range(vma, pg, adr, len)	do { } while (0)
39 
40 /* Flush the icache just on this cpu */
41 extern void __flush_icache_range(unsigned long start, unsigned long end);
42 
43 /* Flush the entire icache on this cpu. */
44 #define __flush_icache() __flush_icache_range(0, CHIP_L1I_CACHE_SIZE())
45 
46 #ifdef CONFIG_SMP
47 /*
48  * When the kernel writes to its own text we need to do an SMP
49  * broadcast to make the L1I coherent everywhere.  This includes
50  * module load and single step.
51  */
52 extern void flush_icache_range(unsigned long start, unsigned long end);
53 #else
54 #define flush_icache_range __flush_icache_range
55 #endif
56 
57 /*
58  * An update to an executable user page requires icache flushing.
59  * We could carefully update only tiles that are running this process,
60  * and rely on the fact that we flush the icache on every context
61  * switch to avoid doing extra work here.  But for now, I'll be
62  * conservative and just do a global icache flush.
63  */
copy_to_user_page(struct vm_area_struct * vma,struct page * page,unsigned long vaddr,void * dst,void * src,int len)64 static inline void copy_to_user_page(struct vm_area_struct *vma,
65 				     struct page *page, unsigned long vaddr,
66 				     void *dst, void *src, int len)
67 {
68 	memcpy(dst, src, len);
69 	if (vma->vm_flags & VM_EXEC) {
70 		flush_icache_range((unsigned long) dst,
71 				   (unsigned long) dst + len);
72 	}
73 }
74 
75 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
76 	memcpy((dst), (src), (len))
77 
78 /*
79  * Invalidate a VA range; pads to L2 cacheline boundaries.
80  *
81  * Note that on TILE64, __inv_buffer() actually flushes modified
82  * cache lines in addition to invalidating them, i.e., it's the
83  * same as __finv_buffer().
84  */
__inv_buffer(void * buffer,size_t size)85 static inline void __inv_buffer(void *buffer, size_t size)
86 {
87 	char *next = (char *)((long)buffer & -L2_CACHE_BYTES);
88 	char *finish = (char *)L2_CACHE_ALIGN((long)buffer + size);
89 	while (next < finish) {
90 		__insn_inv(next);
91 		next += CHIP_INV_STRIDE();
92 	}
93 }
94 
95 /* Flush a VA range; pads to L2 cacheline boundaries. */
__flush_buffer(void * buffer,size_t size)96 static inline void __flush_buffer(void *buffer, size_t size)
97 {
98 	char *next = (char *)((long)buffer & -L2_CACHE_BYTES);
99 	char *finish = (char *)L2_CACHE_ALIGN((long)buffer + size);
100 	while (next < finish) {
101 		__insn_flush(next);
102 		next += CHIP_FLUSH_STRIDE();
103 	}
104 }
105 
106 /* Flush & invalidate a VA range; pads to L2 cacheline boundaries. */
__finv_buffer(void * buffer,size_t size)107 static inline void __finv_buffer(void *buffer, size_t size)
108 {
109 	char *next = (char *)((long)buffer & -L2_CACHE_BYTES);
110 	char *finish = (char *)L2_CACHE_ALIGN((long)buffer + size);
111 	while (next < finish) {
112 		__insn_finv(next);
113 		next += CHIP_FINV_STRIDE();
114 	}
115 }
116 
117 
118 /* Invalidate a VA range and wait for it to be complete. */
inv_buffer(void * buffer,size_t size)119 static inline void inv_buffer(void *buffer, size_t size)
120 {
121 	__inv_buffer(buffer, size);
122 	mb();
123 }
124 
125 /*
126  * Flush a locally-homecached VA range and wait for the evicted
127  * cachelines to hit memory.
128  */
flush_buffer_local(void * buffer,size_t size)129 static inline void flush_buffer_local(void *buffer, size_t size)
130 {
131 	__flush_buffer(buffer, size);
132 	mb_incoherent();
133 }
134 
135 /*
136  * Flush and invalidate a locally-homecached VA range and wait for the
137  * evicted cachelines to hit memory.
138  */
finv_buffer_local(void * buffer,size_t size)139 static inline void finv_buffer_local(void *buffer, size_t size)
140 {
141 	__finv_buffer(buffer, size);
142 	mb_incoherent();
143 }
144 
145 /*
146  * Flush and invalidate a VA range that is homed remotely, waiting
147  * until the memory controller holds the flushed values.  If "hfh" is
148  * true, we will do a more expensive flush involving additional loads
149  * to make sure we have touched all the possible home cpus of a buffer
150  * that is homed with "hash for home".
151  */
152 void finv_buffer_remote(void *buffer, size_t size, int hfh);
153 
154 /*
155  * On SMP systems, when the scheduler does migration-cost autodetection,
156  * it needs a way to flush as much of the CPU's caches as possible:
157  *
158  * TODO: fill this in!
159  */
sched_cacheflush(void)160 static inline void sched_cacheflush(void)
161 {
162 }
163 
164 #endif /* _ASM_TILE_CACHEFLUSH_H */
165