xref: /openbmc/linux/arch/arc/include/asm/cacheflush.h (revision bc33f5e5)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4  *
5  *  vineetg: May 2011: for Non-aliasing VIPT D-cache following can be NOPs
6  *   -flush_cache_dup_mm (fork)
7  *   -likewise for flush_cache_mm (exit/execve)
8  *   -likewise for flush_cache_{range,page} (munmap, exit, COW-break)
9  *
10  *  vineetg: April 2008
11  *   -Added a critical CacheLine flush to copy_to_user_page( ) which
12  *     was causing gdbserver to not setup breakpoints consistently
13  */
14 
15 #ifndef _ASM_CACHEFLUSH_H
16 #define _ASM_CACHEFLUSH_H
17 
18 #include <linux/mm.h>
19 #include <asm/shmparam.h>
20 
21 /*
22  * Semantically we need this because icache doesn't snoop dcache/dma.
23  * However ARC Cache flush requires paddr as well as vaddr, latter not available
24  * in the flush_icache_page() API. So we no-op it but do the equivalent work
25  * in update_mmu_cache()
26  */
27 #define flush_icache_page(vma, page)
28 
29 void flush_cache_all(void);
30 
31 void flush_icache_range(unsigned long kstart, unsigned long kend);
32 void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len);
33 void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr);
34 void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr);
35 
36 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
37 
38 void flush_dcache_page(struct page *page);
39 
40 void dma_cache_wback_inv(phys_addr_t start, unsigned long sz);
41 void dma_cache_inv(phys_addr_t start, unsigned long sz);
42 void dma_cache_wback(phys_addr_t start, unsigned long sz);
43 
44 #define flush_dcache_mmap_lock(mapping)		do { } while (0)
45 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)
46 
47 /* TBD: optimize this */
48 #define flush_cache_vmap(start, end)		flush_cache_all()
49 #define flush_cache_vunmap(start, end)		flush_cache_all()
50 
51 #define flush_cache_dup_mm(mm)			/* called on fork (VIVT only) */
52 
53 #ifndef CONFIG_ARC_CACHE_VIPT_ALIASING
54 
55 #define flush_cache_mm(mm)			/* called on munmap/exit */
56 #define flush_cache_range(mm, u_vstart, u_vend)
57 #define flush_cache_page(vma, u_vaddr, pfn)	/* PF handling/COW-break */
58 
59 #else	/* VIPT aliasing dcache */
60 
61 /* To clear out stale userspace mappings */
62 void flush_cache_mm(struct mm_struct *mm);
63 void flush_cache_range(struct vm_area_struct *vma,
64 	unsigned long start,unsigned long end);
65 void flush_cache_page(struct vm_area_struct *vma,
66 	unsigned long user_addr, unsigned long page);
67 
68 /*
69  * To make sure that userspace mapping is flushed to memory before
70  * get_user_pages() uses a kernel mapping to access the page
71  */
72 #define ARCH_HAS_FLUSH_ANON_PAGE
73 void flush_anon_page(struct vm_area_struct *vma,
74 	struct page *page, unsigned long u_vaddr);
75 
76 #endif	/* CONFIG_ARC_CACHE_VIPT_ALIASING */
77 
78 /*
79  * A new pagecache page has PG_arch_1 clear - thus dcache dirty by default
80  * This works around some PIO based drivers which don't call flush_dcache_page
81  * to record that they dirtied the dcache
82  */
83 #define PG_dc_clean	PG_arch_1
84 
85 #define CACHE_COLORS_NUM	4
86 #define CACHE_COLORS_MSK	(CACHE_COLORS_NUM - 1)
87 #define CACHE_COLOR(addr)	(((unsigned long)(addr) >> (PAGE_SHIFT)) & CACHE_COLORS_MSK)
88 
89 /*
90  * Simple wrapper over config option
91  * Bootup code ensures that hardware matches kernel configuration
92  */
93 static inline int cache_is_vipt_aliasing(void)
94 {
95 	return IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
96 }
97 
98 /*
99  * checks if two addresses (after page aligning) index into same cache set
100  */
101 #define addr_not_cache_congruent(addr1, addr2)				\
102 ({									\
103 	cache_is_vipt_aliasing() ? 					\
104 		(CACHE_COLOR(addr1) != CACHE_COLOR(addr2)) : 0;		\
105 })
106 
107 #define copy_to_user_page(vma, page, vaddr, dst, src, len)		\
108 do {									\
109 	memcpy(dst, src, len);						\
110 	if (vma->vm_flags & VM_EXEC)					\
111 		__sync_icache_dcache((unsigned long)(dst), vaddr, len);	\
112 } while (0)
113 
114 #define copy_from_user_page(vma, page, vaddr, dst, src, len)		\
115 	memcpy(dst, src, len);						\
116 
117 #endif
118