1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * OpenRISC Linux
4  *
5  * Linux architectural port borrowing liberally from similar works of
6  * others.  All original copyrights apply as per the original source
7  * declaration.
8  *
9  * OpenRISC implementation:
10  * Copyright (C) Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
11  * et al.
12  */
13 
14 #ifndef __ASM_CACHEFLUSH_H
15 #define __ASM_CACHEFLUSH_H
16 
17 #include <linux/mm.h>
18 
19 /*
20  * Helper function for flushing or invalidating entire pages from data
21  * and instruction caches. SMP needs a little extra work, since we need
22  * to flush the pages on all cpus.
23  */
24 extern void local_dcache_page_flush(struct page *page);
25 extern void local_icache_page_inv(struct page *page);
26 
27 /*
28  * Data cache flushing always happen on the local cpu. Instruction cache
29  * invalidations need to be broadcasted to all other cpu in the system in
30  * case of SMP configurations.
31  */
32 #ifndef CONFIG_SMP
33 #define dcache_page_flush(page)      local_dcache_page_flush(page)
34 #define icache_page_inv(page)        local_icache_page_inv(page)
35 #else  /* CONFIG_SMP */
36 #define dcache_page_flush(page)      local_dcache_page_flush(page)
37 #define icache_page_inv(page)        smp_icache_page_inv(page)
38 extern void smp_icache_page_inv(struct page *page);
39 #endif /* CONFIG_SMP */
40 
41 /*
42  * Synchronizes caches. Whenever a cpu writes executable code to memory, this
43  * should be called to make sure the processor sees the newly written code.
44  */
45 static inline void sync_icache_dcache(struct page *page)
46 {
47 	if (!IS_ENABLED(CONFIG_DCACHE_WRITETHROUGH))
48 		dcache_page_flush(page);
49 	icache_page_inv(page);
50 }
51 
52 /*
53  * Pages with this bit set need not be flushed/invalidated, since
54  * they have not changed since last flush. New pages start with
55  * PG_arch_1 not set and are therefore dirty by default.
56  */
57 #define PG_dc_clean                  PG_arch_1
58 
59 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
60 static inline void flush_dcache_page(struct page *page)
61 {
62 	clear_bit(PG_dc_clean, &page->flags);
63 }
64 
65 /*
66  * Other interfaces are not required since we do not have virtually
67  * indexed or tagged caches. So we can use the default here.
68  */
69 #define flush_cache_all()				do { } while (0)
70 #define flush_cache_mm(mm)				do { } while (0)
71 #define flush_cache_dup_mm(mm)				do { } while (0)
72 #define flush_cache_range(vma, start, end)		do { } while (0)
73 #define flush_cache_page(vma, vmaddr, pfn)		do { } while (0)
74 #define flush_dcache_mmap_lock(mapping)			do { } while (0)
75 #define flush_dcache_mmap_unlock(mapping)		do { } while (0)
76 #define flush_icache_range(start, end)			do { } while (0)
77 #define flush_icache_page(vma, pg)			do { } while (0)
78 #define flush_icache_user_range(vma, pg, adr, len)	do { } while (0)
79 #define flush_cache_vmap(start, end)			do { } while (0)
80 #define flush_cache_vunmap(start, end)			do { } while (0)
81 
82 #define copy_to_user_page(vma, page, vaddr, dst, src, len)           \
83 	do {                                                         \
84 		memcpy(dst, src, len);                               \
85 		if (vma->vm_flags & VM_EXEC)                         \
86 			sync_icache_dcache(page);                    \
87 	} while (0)
88 
89 #define copy_from_user_page(vma, page, vaddr, dst, src, len)         \
90 	memcpy(dst, src, len)
91 
92 #endif /* __ASM_CACHEFLUSH_H */
93