xref: /openbmc/linux/arch/arc/include/asm/cacheflush.h (revision 78700c0a)
1 /*
2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  *  vineetg: May 2011: for Non-aliasing VIPT D-cache following can be NOPs
9  *   -flush_cache_dup_mm (fork)
10  *   -likewise for flush_cache_mm (exit/execve)
11  *   -likewise for flush_cache_{range,page} (munmap, exit, COW-break)
12  *
13  *  vineetg: April 2008
14  *   -Added a critical CacheLine flush to copy_to_user_page( ) which
15  *     was causing gdbserver to not setup breakpoints consistently
16  */
17 
18 #ifndef _ASM_CACHEFLUSH_H
19 #define _ASM_CACHEFLUSH_H
20 
21 #include <linux/mm.h>
22 #include <asm/shmparam.h>
23 
24 /*
25  * Semantically we need this because icache doesn't snoop dcache/dma.
26  * However ARC Cache flush requires paddr as well as vaddr, latter not available
27  * in the flush_icache_page() API. So we no-op it but do the equivalent work
28  * in update_mmu_cache()
29  */
30 #define flush_icache_page(vma, page)
31 
32 void flush_cache_all(void);
33 
34 void flush_icache_range(unsigned long kstart, unsigned long kend);
35 void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len);
36 void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr);
37 void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr);
38 
39 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
40 
41 void flush_dcache_page(struct page *page);
42 
43 void dma_cache_wback_inv(phys_addr_t start, unsigned long sz);
44 void dma_cache_inv(phys_addr_t start, unsigned long sz);
45 void dma_cache_wback(phys_addr_t start, unsigned long sz);
46 
47 #define flush_dcache_mmap_lock(mapping)		do { } while (0)
48 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)
49 
50 /* TBD: optimize this */
51 #define flush_cache_vmap(start, end)		flush_cache_all()
52 #define flush_cache_vunmap(start, end)		flush_cache_all()
53 
54 #define flush_cache_dup_mm(mm)			/* called on fork (VIVT only) */
55 
56 #ifndef CONFIG_ARC_CACHE_VIPT_ALIASING
57 
58 #define flush_cache_mm(mm)			/* called on munmap/exit */
59 #define flush_cache_range(mm, u_vstart, u_vend)
60 #define flush_cache_page(vma, u_vaddr, pfn)	/* PF handling/COW-break */
61 
62 #else	/* VIPT aliasing dcache */
63 
64 /* To clear out stale userspace mappings */
65 void flush_cache_mm(struct mm_struct *mm);
66 void flush_cache_range(struct vm_area_struct *vma,
67 	unsigned long start,unsigned long end);
68 void flush_cache_page(struct vm_area_struct *vma,
69 	unsigned long user_addr, unsigned long page);
70 
71 /*
72  * To make sure that userspace mapping is flushed to memory before
73  * get_user_pages() uses a kernel mapping to access the page
74  */
75 #define ARCH_HAS_FLUSH_ANON_PAGE
76 void flush_anon_page(struct vm_area_struct *vma,
77 	struct page *page, unsigned long u_vaddr);
78 
79 #endif	/* CONFIG_ARC_CACHE_VIPT_ALIASING */
80 
81 /*
82  * A new pagecache page has PG_arch_1 clear - thus dcache dirty by default
83  * This works around some PIO based drivers which don't call flush_dcache_page
84  * to record that they dirtied the dcache
85  */
86 #define PG_dc_clean	PG_arch_1
87 
88 /*
89  * Simple wrapper over config option
90  * Bootup code ensures that hardware matches kernel configuration
91  */
92 static inline int cache_is_vipt_aliasing(void)
93 {
94 	return IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
95 }
96 
97 #define CACHE_COLOR(addr)	(((unsigned long)(addr) >> (PAGE_SHIFT)) & 1)
98 
99 /*
100  * checks if two addresses (after page aligning) index into same cache set
101  */
102 #define addr_not_cache_congruent(addr1, addr2)				\
103 ({									\
104 	cache_is_vipt_aliasing() ? 					\
105 		(CACHE_COLOR(addr1) != CACHE_COLOR(addr2)) : 0;		\
106 })
107 
108 #define copy_to_user_page(vma, page, vaddr, dst, src, len)		\
109 do {									\
110 	memcpy(dst, src, len);						\
111 	if (vma->vm_flags & VM_EXEC)					\
112 		__sync_icache_dcache((unsigned long)(dst), vaddr, len);	\
113 } while (0)
114 
115 #define copy_from_user_page(vma, page, vaddr, dst, src, len)		\
116 	memcpy(dst, src, len);						\
117 
118 #endif
119