xref: /linux/arch/arm64/include/asm/cache.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 ARM Ltd.
4  */
5 #ifndef __ASM_CACHE_H
6 #define __ASM_CACHE_H
7 
8 #define L1_CACHE_SHIFT		(6)
9 #define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)
10 
11 #define CLIDR_LOUU_SHIFT	27
12 #define CLIDR_LOC_SHIFT		24
13 #define CLIDR_LOUIS_SHIFT	21
14 
15 #define CLIDR_LOUU(clidr)	(((clidr) >> CLIDR_LOUU_SHIFT) & 0x7)
16 #define CLIDR_LOC(clidr)	(((clidr) >> CLIDR_LOC_SHIFT) & 0x7)
17 #define CLIDR_LOUIS(clidr)	(((clidr) >> CLIDR_LOUIS_SHIFT) & 0x7)
18 
19 /* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
20 #define CLIDR_CTYPE_SHIFT(level)	(3 * (level - 1))
21 #define CLIDR_CTYPE_MASK(level)		(7 << CLIDR_CTYPE_SHIFT(level))
22 #define CLIDR_CTYPE(clidr, level)	\
23 	(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
24 
25 /* Ttypen, bits [2(n - 1) + 34 : 2(n - 1) + 33], for n = 1 to 7 */
26 #define CLIDR_TTYPE_SHIFT(level)	(2 * ((level) - 1) + CLIDR_EL1_Ttypen_SHIFT)
27 
28 /*
29  * Memory returned by kmalloc() may be used for DMA, so we must make
30  * sure that all such allocations are cache aligned. Otherwise,
31  * unrelated code may cause parts of the buffer to be read into the
32  * cache before the transfer is done, causing old data to be seen by
33  * the CPU.
34  */
35 #define ARCH_DMA_MINALIGN	(128)
36 #define ARCH_KMALLOC_MINALIGN	(8)
37 
38 #ifndef __ASSEMBLY__
39 
40 #include <linux/bitops.h>
41 #include <linux/kasan-enabled.h>
42 
43 #include <asm/cputype.h>
44 #include <asm/mte-def.h>
45 #include <asm/sysreg.h>
46 
47 #ifdef CONFIG_KASAN_SW_TAGS
48 #define ARCH_SLAB_MINALIGN	(1ULL << KASAN_SHADOW_SCALE_SHIFT)
49 #elif defined(CONFIG_KASAN_HW_TAGS)
50 static inline unsigned int arch_slab_minalign(void)
51 {
52 	return kasan_hw_tags_enabled() ? MTE_GRANULE_SIZE :
53 					 __alignof__(unsigned long long);
54 }
55 #define arch_slab_minalign() arch_slab_minalign()
56 #endif
57 
58 #define CTR_L1IP(ctr)		SYS_FIELD_GET(CTR_EL0, L1Ip, ctr)
59 
60 #define ICACHEF_ALIASING	0
61 extern unsigned long __icache_flags;
62 
63 /*
64  * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
65  * permitted in the I-cache.
66  */
67 static inline int icache_is_aliasing(void)
68 {
69 	return test_bit(ICACHEF_ALIASING, &__icache_flags);
70 }
71 
72 static inline u32 cache_type_cwg(void)
73 {
74 	return SYS_FIELD_GET(CTR_EL0, CWG, read_cpuid_cachetype());
75 }
76 
77 #define __read_mostly __section(".data..read_mostly")
78 
79 static inline int cache_line_size_of_cpu(void)
80 {
81 	u32 cwg = cache_type_cwg();
82 
83 	return cwg ? 4 << cwg : ARCH_DMA_MINALIGN;
84 }
85 
86 int cache_line_size(void);
87 
88 #define dma_get_cache_alignment	cache_line_size
89 
90 /*
91  * Read the effective value of CTR_EL0.
92  *
93  * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a),
94  * section D10.2.33 "CTR_EL0, Cache Type Register" :
95  *
96  * CTR_EL0.IDC reports the data cache clean requirements for
97  * instruction to data coherence.
98  *
99  *  0 - dcache clean to PoU is required unless :
100  *     (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0)
101  *  1 - dcache clean to PoU is not required for i-to-d coherence.
102  *
103  * This routine provides the CTR_EL0 with the IDC field updated to the
104  * effective state.
105  */
106 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void)
107 {
108 	u32 ctr = read_cpuid_cachetype();
109 
110 	if (!(ctr & BIT(CTR_EL0_IDC_SHIFT))) {
111 		u64 clidr = read_sysreg(clidr_el1);
112 
113 		if (CLIDR_LOC(clidr) == 0 ||
114 		    (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0))
115 			ctr |= BIT(CTR_EL0_IDC_SHIFT);
116 	}
117 
118 	return ctr;
119 }
120 
121 #endif	/* __ASSEMBLY__ */
122 
123 #endif
124