xref: /openbmc/linux/arch/arm64/include/asm/cache.h (revision adc286e6)
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 #include <asm/cputype.h>
9 #include <asm/mte-def.h>
10 
11 #define CTR_L1IP_SHIFT		14
12 #define CTR_L1IP_MASK		3
13 #define CTR_DMINLINE_SHIFT	16
14 #define CTR_IMINLINE_SHIFT	0
15 #define CTR_IMINLINE_MASK	0xf
16 #define CTR_ERG_SHIFT		20
17 #define CTR_CWG_SHIFT		24
18 #define CTR_CWG_MASK		15
19 #define CTR_IDC_SHIFT		28
20 #define CTR_DIC_SHIFT		29
21 
22 #define CTR_CACHE_MINLINE_MASK	\
23 	(0xf << CTR_DMINLINE_SHIFT | CTR_IMINLINE_MASK << CTR_IMINLINE_SHIFT)
24 
25 #define CTR_L1IP(ctr)		(((ctr) >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK)
26 
27 #define ICACHE_POLICY_VPIPT	0
28 #define ICACHE_POLICY_RESERVED	1
29 #define ICACHE_POLICY_VIPT	2
30 #define ICACHE_POLICY_PIPT	3
31 
32 #define L1_CACHE_SHIFT		(6)
33 #define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)
34 
35 
36 #define CLIDR_LOUU_SHIFT	27
37 #define CLIDR_LOC_SHIFT		24
38 #define CLIDR_LOUIS_SHIFT	21
39 
40 #define CLIDR_LOUU(clidr)	(((clidr) >> CLIDR_LOUU_SHIFT) & 0x7)
41 #define CLIDR_LOC(clidr)	(((clidr) >> CLIDR_LOC_SHIFT) & 0x7)
42 #define CLIDR_LOUIS(clidr)	(((clidr) >> CLIDR_LOUIS_SHIFT) & 0x7)
43 
44 /*
45  * Memory returned by kmalloc() may be used for DMA, so we must make
46  * sure that all such allocations are cache aligned. Otherwise,
47  * unrelated code may cause parts of the buffer to be read into the
48  * cache before the transfer is done, causing old data to be seen by
49  * the CPU.
50  */
51 #define ARCH_DMA_MINALIGN	(128)
52 
53 #ifndef __ASSEMBLY__
54 
55 #include <linux/bitops.h>
56 #include <linux/kasan-enabled.h>
57 
58 #ifdef CONFIG_KASAN_SW_TAGS
59 #define ARCH_SLAB_MINALIGN	(1ULL << KASAN_SHADOW_SCALE_SHIFT)
60 #elif defined(CONFIG_KASAN_HW_TAGS)
61 static inline unsigned int arch_slab_minalign(void)
62 {
63 	return kasan_hw_tags_enabled() ? MTE_GRANULE_SIZE :
64 					 __alignof__(unsigned long long);
65 }
66 #define arch_slab_minalign() arch_slab_minalign()
67 #endif
68 
69 #define ICACHEF_ALIASING	0
70 #define ICACHEF_VPIPT		1
71 extern unsigned long __icache_flags;
72 
73 /*
74  * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
75  * permitted in the I-cache.
76  */
77 static inline int icache_is_aliasing(void)
78 {
79 	return test_bit(ICACHEF_ALIASING, &__icache_flags);
80 }
81 
82 static __always_inline int icache_is_vpipt(void)
83 {
84 	return test_bit(ICACHEF_VPIPT, &__icache_flags);
85 }
86 
87 static inline u32 cache_type_cwg(void)
88 {
89 	return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK;
90 }
91 
92 #define __read_mostly __section(".data..read_mostly")
93 
94 static inline int cache_line_size_of_cpu(void)
95 {
96 	u32 cwg = cache_type_cwg();
97 
98 	return cwg ? 4 << cwg : ARCH_DMA_MINALIGN;
99 }
100 
101 int cache_line_size(void);
102 
103 /*
104  * Read the effective value of CTR_EL0.
105  *
106  * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a),
107  * section D10.2.33 "CTR_EL0, Cache Type Register" :
108  *
109  * CTR_EL0.IDC reports the data cache clean requirements for
110  * instruction to data coherence.
111  *
112  *  0 - dcache clean to PoU is required unless :
113  *     (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0)
114  *  1 - dcache clean to PoU is not required for i-to-d coherence.
115  *
116  * This routine provides the CTR_EL0 with the IDC field updated to the
117  * effective state.
118  */
119 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void)
120 {
121 	u32 ctr = read_cpuid_cachetype();
122 
123 	if (!(ctr & BIT(CTR_IDC_SHIFT))) {
124 		u64 clidr = read_sysreg(clidr_el1);
125 
126 		if (CLIDR_LOC(clidr) == 0 ||
127 		    (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0))
128 			ctr |= BIT(CTR_IDC_SHIFT);
129 	}
130 
131 	return ctr;
132 }
133 
134 #endif	/* __ASSEMBLY__ */
135 
136 #endif
137