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