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 /* 20 * Memory returned by kmalloc() may be used for DMA, so we must make 21 * sure that all such allocations are cache aligned. Otherwise, 22 * unrelated code may cause parts of the buffer to be read into the 23 * cache before the transfer is done, causing old data to be seen by 24 * the CPU. 25 */ 26 #define ARCH_DMA_MINALIGN (128) 27 28 #ifndef __ASSEMBLY__ 29 30 #include <linux/bitops.h> 31 #include <linux/kasan-enabled.h> 32 33 #include <asm/cputype.h> 34 #include <asm/mte-def.h> 35 #include <asm/sysreg.h> 36 37 #ifdef CONFIG_KASAN_SW_TAGS 38 #define ARCH_SLAB_MINALIGN (1ULL << KASAN_SHADOW_SCALE_SHIFT) 39 #elif defined(CONFIG_KASAN_HW_TAGS) 40 static inline unsigned int arch_slab_minalign(void) 41 { 42 return kasan_hw_tags_enabled() ? MTE_GRANULE_SIZE : 43 __alignof__(unsigned long long); 44 } 45 #define arch_slab_minalign() arch_slab_minalign() 46 #endif 47 48 #define CTR_L1IP(ctr) SYS_FIELD_GET(CTR_EL0, L1Ip, ctr) 49 50 #define ICACHEF_ALIASING 0 51 #define ICACHEF_VPIPT 1 52 extern unsigned long __icache_flags; 53 54 /* 55 * Whilst the D-side always behaves as PIPT on AArch64, aliasing is 56 * permitted in the I-cache. 57 */ 58 static inline int icache_is_aliasing(void) 59 { 60 return test_bit(ICACHEF_ALIASING, &__icache_flags); 61 } 62 63 static __always_inline int icache_is_vpipt(void) 64 { 65 return test_bit(ICACHEF_VPIPT, &__icache_flags); 66 } 67 68 static inline u32 cache_type_cwg(void) 69 { 70 return SYS_FIELD_GET(CTR_EL0, CWG, read_cpuid_cachetype()); 71 } 72 73 #define __read_mostly __section(".data..read_mostly") 74 75 static inline int cache_line_size_of_cpu(void) 76 { 77 u32 cwg = cache_type_cwg(); 78 79 return cwg ? 4 << cwg : ARCH_DMA_MINALIGN; 80 } 81 82 int cache_line_size(void); 83 84 /* 85 * Read the effective value of CTR_EL0. 86 * 87 * According to ARM ARM for ARMv8-A (ARM DDI 0487C.a), 88 * section D10.2.33 "CTR_EL0, Cache Type Register" : 89 * 90 * CTR_EL0.IDC reports the data cache clean requirements for 91 * instruction to data coherence. 92 * 93 * 0 - dcache clean to PoU is required unless : 94 * (CLIDR_EL1.LoC == 0) || (CLIDR_EL1.LoUIS == 0 && CLIDR_EL1.LoUU == 0) 95 * 1 - dcache clean to PoU is not required for i-to-d coherence. 96 * 97 * This routine provides the CTR_EL0 with the IDC field updated to the 98 * effective state. 99 */ 100 static inline u32 __attribute_const__ read_cpuid_effective_cachetype(void) 101 { 102 u32 ctr = read_cpuid_cachetype(); 103 104 if (!(ctr & BIT(CTR_EL0_IDC_SHIFT))) { 105 u64 clidr = read_sysreg(clidr_el1); 106 107 if (CLIDR_LOC(clidr) == 0 || 108 (CLIDR_LOUIS(clidr) == 0 && CLIDR_LOUU(clidr) == 0)) 109 ctr |= BIT(CTR_EL0_IDC_SHIFT); 110 } 111 112 return ctr; 113 } 114 115 #endif /* __ASSEMBLY__ */ 116 117 #endif 118