xref: /openbmc/linux/arch/arm64/include/asm/cache.h (revision 3d40aed8)
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 #define ICACHEF_VPIPT		1
62 extern unsigned long __icache_flags;
63 
64 /*
65  * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
66  * permitted in the I-cache.
67  */
68 static inline int icache_is_aliasing(void)
69 {
70 	return test_bit(ICACHEF_ALIASING, &__icache_flags);
71 }
72 
73 static __always_inline int icache_is_vpipt(void)
74 {
75 	return test_bit(ICACHEF_VPIPT, &__icache_flags);
76 }
77 
78 static inline u32 cache_type_cwg(void)
79 {
80 	return SYS_FIELD_GET(CTR_EL0, CWG, read_cpuid_cachetype());
81 }
82 
83 #define __read_mostly __section(".data..read_mostly")
84 
85 static inline int cache_line_size_of_cpu(void)
86 {
87 	u32 cwg = cache_type_cwg();
88 
89 	return cwg ? 4 << cwg : ARCH_DMA_MINALIGN;
90 }
91 
92 int cache_line_size(void);
93 
94 #define dma_get_cache_alignment	cache_line_size
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_EL0_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_EL0_IDC_SHIFT);
122 	}
123 
124 	return ctr;
125 }
126 
127 #endif	/* __ASSEMBLY__ */
128 
129 #endif
130