xref: /openbmc/linux/arch/arm64/include/asm/cache.h (revision 8938c48f)
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 
10 #define CTR_L1IP_SHIFT		14
11 #define CTR_L1IP_MASK		3
12 #define CTR_DMINLINE_SHIFT	16
13 #define CTR_IMINLINE_SHIFT	0
14 #define CTR_IMINLINE_MASK	0xf
15 #define CTR_ERG_SHIFT		20
16 #define CTR_CWG_SHIFT		24
17 #define CTR_CWG_MASK		15
18 #define CTR_IDC_SHIFT		28
19 #define CTR_DIC_SHIFT		29
20 
21 #define CTR_CACHE_MINLINE_MASK	\
22 	(0xf << CTR_DMINLINE_SHIFT | CTR_IMINLINE_MASK << CTR_IMINLINE_SHIFT)
23 
24 #define CTR_L1IP(ctr)		(((ctr) >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK)
25 
26 #define ICACHE_POLICY_VPIPT	0
27 #define ICACHE_POLICY_RESERVED	1
28 #define ICACHE_POLICY_VIPT	2
29 #define ICACHE_POLICY_PIPT	3
30 
31 #define L1_CACHE_SHIFT		(6)
32 #define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)
33 
34 
35 #define CLIDR_LOUU_SHIFT	27
36 #define CLIDR_LOC_SHIFT		24
37 #define CLIDR_LOUIS_SHIFT	21
38 
39 #define CLIDR_LOUU(clidr)	(((clidr) >> CLIDR_LOUU_SHIFT) & 0x7)
40 #define CLIDR_LOC(clidr)	(((clidr) >> CLIDR_LOC_SHIFT) & 0x7)
41 #define CLIDR_LOUIS(clidr)	(((clidr) >> CLIDR_LOUIS_SHIFT) & 0x7)
42 
43 /*
44  * Memory returned by kmalloc() may be used for DMA, so we must make
45  * sure that all such allocations are cache aligned. Otherwise,
46  * unrelated code may cause parts of the buffer to be read into the
47  * cache before the transfer is done, causing old data to be seen by
48  * the CPU.
49  */
50 #define ARCH_DMA_MINALIGN	(128)
51 
52 #ifdef CONFIG_KASAN_SW_TAGS
53 #define ARCH_SLAB_MINALIGN	(1ULL << KASAN_SHADOW_SCALE_SHIFT)
54 #elif defined(CONFIG_KASAN_HW_TAGS)
55 #define ARCH_SLAB_MINALIGN	MTE_GRANULE_SIZE
56 #endif
57 
58 #ifndef __ASSEMBLY__
59 
60 #include <linux/bitops.h>
61 
62 #define ICACHEF_ALIASING	0
63 #define ICACHEF_VPIPT		1
64 extern unsigned long __icache_flags;
65 
66 /*
67  * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
68  * permitted in the I-cache.
69  */
70 static inline int icache_is_aliasing(void)
71 {
72 	return test_bit(ICACHEF_ALIASING, &__icache_flags);
73 }
74 
75 static __always_inline int icache_is_vpipt(void)
76 {
77 	return test_bit(ICACHEF_VPIPT, &__icache_flags);
78 }
79 
80 static inline u32 cache_type_cwg(void)
81 {
82 	return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK;
83 }
84 
85 #define __read_mostly __section(".data..read_mostly")
86 
87 static inline int cache_line_size_of_cpu(void)
88 {
89 	u32 cwg = cache_type_cwg();
90 
91 	return cwg ? 4 << cwg : ARCH_DMA_MINALIGN;
92 }
93 
94 int cache_line_size(void);
95 
96 /*
97  * Read the effective value of CTR_EL0.
98  *
99  * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a),
100  * section D10.2.33 "CTR_EL0, Cache Type Register" :
101  *
102  * CTR_EL0.IDC reports the data cache clean requirements for
103  * instruction to data coherence.
104  *
105  *  0 - dcache clean to PoU is required unless :
106  *     (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0)
107  *  1 - dcache clean to PoU is not required for i-to-d coherence.
108  *
109  * This routine provides the CTR_EL0 with the IDC field updated to the
110  * effective state.
111  */
112 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void)
113 {
114 	u32 ctr = read_cpuid_cachetype();
115 
116 	if (!(ctr & BIT(CTR_IDC_SHIFT))) {
117 		u64 clidr = read_sysreg(clidr_el1);
118 
119 		if (CLIDR_LOC(clidr) == 0 ||
120 		    (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0))
121 			ctr |= BIT(CTR_IDC_SHIFT);
122 	}
123 
124 	return ctr;
125 }
126 
127 #endif	/* __ASSEMBLY__ */
128 
129 #endif
130