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_VIPT 2 28 #define ICACHE_POLICY_PIPT 3 29 30 #define L1_CACHE_SHIFT (6) 31 #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) 32 33 34 #define CLIDR_LOUU_SHIFT 27 35 #define CLIDR_LOC_SHIFT 24 36 #define CLIDR_LOUIS_SHIFT 21 37 38 #define CLIDR_LOUU(clidr) (((clidr) >> CLIDR_LOUU_SHIFT) & 0x7) 39 #define CLIDR_LOC(clidr) (((clidr) >> CLIDR_LOC_SHIFT) & 0x7) 40 #define CLIDR_LOUIS(clidr) (((clidr) >> CLIDR_LOUIS_SHIFT) & 0x7) 41 42 /* 43 * Memory returned by kmalloc() may be used for DMA, so we must make 44 * sure that all such allocations are cache aligned. Otherwise, 45 * unrelated code may cause parts of the buffer to be read into the 46 * cache before the transfer is done, causing old data to be seen by 47 * the CPU. 48 */ 49 #define ARCH_DMA_MINALIGN (128) 50 51 #ifdef CONFIG_KASAN_SW_TAGS 52 #define ARCH_SLAB_MINALIGN (1ULL << KASAN_SHADOW_SCALE_SHIFT) 53 #endif 54 55 #ifndef __ASSEMBLY__ 56 57 #include <linux/bitops.h> 58 59 #define ICACHEF_ALIASING 0 60 #define ICACHEF_VPIPT 1 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 __always_inline int icache_is_vpipt(void) 73 { 74 return test_bit(ICACHEF_VPIPT, &__icache_flags); 75 } 76 77 static inline u32 cache_type_cwg(void) 78 { 79 return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK; 80 } 81 82 #define __read_mostly __section(.data..read_mostly) 83 84 static inline int cache_line_size_of_cpu(void) 85 { 86 u32 cwg = cache_type_cwg(); 87 88 return cwg ? 4 << cwg : ARCH_DMA_MINALIGN; 89 } 90 91 int cache_line_size(void); 92 93 /* 94 * Read the effective value of CTR_EL0. 95 * 96 * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a), 97 * section D10.2.33 "CTR_EL0, Cache Type Register" : 98 * 99 * CTR_EL0.IDC reports the data cache clean requirements for 100 * instruction to data coherence. 101 * 102 * 0 - dcache clean to PoU is required unless : 103 * (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0) 104 * 1 - dcache clean to PoU is not required for i-to-d coherence. 105 * 106 * This routine provides the CTR_EL0 with the IDC field updated to the 107 * effective state. 108 */ 109 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void) 110 { 111 u32 ctr = read_cpuid_cachetype(); 112 113 if (!(ctr & BIT(CTR_IDC_SHIFT))) { 114 u64 clidr = read_sysreg(clidr_el1); 115 116 if (CLIDR_LOC(clidr) == 0 || 117 (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0)) 118 ctr |= BIT(CTR_IDC_SHIFT); 119 } 120 121 return ctr; 122 } 123 124 #endif /* __ASSEMBLY__ */ 125 126 #endif 127