1 /* 2 * Copyright (C) 2012 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 #ifndef __ASM_CACHE_H 17 #define __ASM_CACHE_H 18 19 #include <asm/cputype.h> 20 21 #define CTR_L1IP_SHIFT 14 22 #define CTR_L1IP_MASK 3 23 #define CTR_DMINLINE_SHIFT 16 24 #define CTR_IMINLINE_SHIFT 0 25 #define CTR_ERG_SHIFT 20 26 #define CTR_CWG_SHIFT 24 27 #define CTR_CWG_MASK 15 28 #define CTR_IDC_SHIFT 28 29 #define CTR_DIC_SHIFT 29 30 31 #define CTR_CACHE_MINLINE_MASK \ 32 (0xf << CTR_DMINLINE_SHIFT | 0xf << CTR_IMINLINE_SHIFT) 33 34 #define CTR_L1IP(ctr) (((ctr) >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK) 35 36 #define ICACHE_POLICY_VPIPT 0 37 #define ICACHE_POLICY_VIPT 2 38 #define ICACHE_POLICY_PIPT 3 39 40 #define L1_CACHE_SHIFT (6) 41 #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) 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 #ifndef __ASSEMBLY__ 53 54 #include <linux/bitops.h> 55 56 #define ICACHEF_ALIASING 0 57 #define ICACHEF_VPIPT 1 58 extern unsigned long __icache_flags; 59 60 /* 61 * Whilst the D-side always behaves as PIPT on AArch64, aliasing is 62 * permitted in the I-cache. 63 */ 64 static inline int icache_is_aliasing(void) 65 { 66 return test_bit(ICACHEF_ALIASING, &__icache_flags); 67 } 68 69 static inline int icache_is_vpipt(void) 70 { 71 return test_bit(ICACHEF_VPIPT, &__icache_flags); 72 } 73 74 static inline u32 cache_type_cwg(void) 75 { 76 return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK; 77 } 78 79 #define __read_mostly __attribute__((__section__(".data..read_mostly"))) 80 81 static inline int cache_line_size(void) 82 { 83 u32 cwg = cache_type_cwg(); 84 return cwg ? 4 << cwg : ARCH_DMA_MINALIGN; 85 } 86 87 #endif /* __ASSEMBLY__ */ 88 89 #endif 90