xref: /openbmc/linux/arch/arm64/include/asm/cache.h (revision 84b102f5)
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-kasan.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 #ifdef CONFIG_KASAN_SW_TAGS
54 #define ARCH_SLAB_MINALIGN	(1ULL << KASAN_SHADOW_SCALE_SHIFT)
55 #elif defined(CONFIG_KASAN_HW_TAGS)
56 #define ARCH_SLAB_MINALIGN	MTE_GRANULE_SIZE
57 #endif
58 
59 #ifndef __ASSEMBLY__
60 
61 #include <linux/bitops.h>
62 
63 #define ICACHEF_ALIASING	0
64 #define ICACHEF_VPIPT		1
65 extern unsigned long __icache_flags;
66 
67 /*
68  * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
69  * permitted in the I-cache.
70  */
71 static inline int icache_is_aliasing(void)
72 {
73 	return test_bit(ICACHEF_ALIASING, &__icache_flags);
74 }
75 
76 static __always_inline int icache_is_vpipt(void)
77 {
78 	return test_bit(ICACHEF_VPIPT, &__icache_flags);
79 }
80 
81 static inline u32 cache_type_cwg(void)
82 {
83 	return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK;
84 }
85 
86 #define __read_mostly __section(".data..read_mostly")
87 
88 static inline int cache_line_size_of_cpu(void)
89 {
90 	u32 cwg = cache_type_cwg();
91 
92 	return cwg ? 4 << cwg : ARCH_DMA_MINALIGN;
93 }
94 
95 int cache_line_size(void);
96 
97 /*
98  * Read the effective value of CTR_EL0.
99  *
100  * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a),
101  * section D10.2.33 "CTR_EL0, Cache Type Register" :
102  *
103  * CTR_EL0.IDC reports the data cache clean requirements for
104  * instruction to data coherence.
105  *
106  *  0 - dcache clean to PoU is required unless :
107  *     (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0)
108  *  1 - dcache clean to PoU is not required for i-to-d coherence.
109  *
110  * This routine provides the CTR_EL0 with the IDC field updated to the
111  * effective state.
112  */
113 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void)
114 {
115 	u32 ctr = read_cpuid_cachetype();
116 
117 	if (!(ctr & BIT(CTR_IDC_SHIFT))) {
118 		u64 clidr = read_sysreg(clidr_el1);
119 
120 		if (CLIDR_LOC(clidr) == 0 ||
121 		    (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0))
122 			ctr |= BIT(CTR_IDC_SHIFT);
123 	}
124 
125 	return ctr;
126 }
127 
128 #endif	/* __ASSEMBLY__ */
129 
130 #endif
131