xref: /openbmc/u-boot/arch/arm/lib/cache.c (revision 544acb07)
1 /*
2  * (C) Copyright 2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /* for now: just dummy functions to satisfy the linker */
9 
10 #include <common.h>
11 #include <malloc.h>
12 
13 /*
14  * Flush range from all levels of d-cache/unified-cache.
15  * Affects the range [start, start + size - 1].
16  */
17 __weak void flush_cache(unsigned long start, unsigned long size)
18 {
19 	flush_dcache_range(start, start + size);
20 }
21 
22 /*
23  * Default implementation:
24  * do a range flush for the entire range
25  */
26 __weak void flush_dcache_all(void)
27 {
28 	flush_cache(0, ~0);
29 }
30 
31 /*
32  * Default implementation of enable_caches()
33  * Real implementation should be in platform code
34  */
35 __weak void enable_caches(void)
36 {
37 	puts("WARNING: Caches not enabled\n");
38 }
39 
40 __weak void invalidate_dcache_range(unsigned long start, unsigned long stop)
41 {
42 	/* An empty stub, real implementation should be in platform code */
43 }
44 __weak void flush_dcache_range(unsigned long start, unsigned long stop)
45 {
46 	/* An empty stub, real implementation should be in platform code */
47 }
48 
49 #ifdef CONFIG_SYS_NONCACHED_MEMORY
50 /*
51  * Reserve one MMU section worth of address space below the malloc() area that
52  * will be mapped uncached.
53  */
54 static unsigned long noncached_start;
55 static unsigned long noncached_end;
56 static unsigned long noncached_next;
57 
58 void noncached_init(void)
59 {
60 	phys_addr_t start, end;
61 	size_t size;
62 
63 	end = ALIGN(mem_malloc_start, MMU_SECTION_SIZE) - MMU_SECTION_SIZE;
64 	size = ALIGN(CONFIG_SYS_NONCACHED_MEMORY, MMU_SECTION_SIZE);
65 	start = end - size;
66 
67 	debug("mapping memory %pa-%pa non-cached\n", &start, &end);
68 
69 	noncached_start = start;
70 	noncached_end = end;
71 	noncached_next = start;
72 
73 #ifndef CONFIG_SYS_DCACHE_OFF
74 	mmu_set_region_dcache_behaviour(noncached_start, size, DCACHE_OFF);
75 #endif
76 }
77 
78 phys_addr_t noncached_alloc(size_t size, size_t align)
79 {
80 	phys_addr_t next = ALIGN(noncached_next, align);
81 
82 	if (next >= noncached_end || (noncached_end - next) < size)
83 		return 0;
84 
85 	debug("allocated %zu bytes of uncached memory @%pa\n", size, &next);
86 	noncached_next = next + size;
87 
88 	return next;
89 }
90 #endif /* CONFIG_SYS_NONCACHED_MEMORY */
91 
92 #if defined(CONFIG_SYS_THUMB_BUILD)
93 void invalidate_l2_cache(void)
94 {
95 	unsigned int val = 0;
96 
97 	asm volatile("mcr p15, 1, %0, c15, c11, 0 @ invl l2 cache"
98 		: : "r" (val) : "cc");
99 	isb();
100 }
101 #endif
102