1/* 2 * Cache-handling routined for MIPS CPUs 3 * 4 * Copyright (c) 2003 Wolfgang Denk <wd@denx.de> 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9#include <asm-offsets.h> 10#include <config.h> 11#include <asm/asm.h> 12#include <asm/regdef.h> 13#include <asm/mipsregs.h> 14#include <asm/addrspace.h> 15#include <asm/cacheops.h> 16 17#ifndef CONFIG_SYS_MIPS_CACHE_MODE 18#define CONFIG_SYS_MIPS_CACHE_MODE CONF_CM_CACHABLE_NONCOHERENT 19#endif 20 21#define INDEX_BASE CKSEG0 22 23 .macro f_fill64 dst, offset, val 24 LONG_S \val, (\offset + 0 * LONGSIZE)(\dst) 25 LONG_S \val, (\offset + 1 * LONGSIZE)(\dst) 26 LONG_S \val, (\offset + 2 * LONGSIZE)(\dst) 27 LONG_S \val, (\offset + 3 * LONGSIZE)(\dst) 28 LONG_S \val, (\offset + 4 * LONGSIZE)(\dst) 29 LONG_S \val, (\offset + 5 * LONGSIZE)(\dst) 30 LONG_S \val, (\offset + 6 * LONGSIZE)(\dst) 31 LONG_S \val, (\offset + 7 * LONGSIZE)(\dst) 32#if LONGSIZE == 4 33 LONG_S \val, (\offset + 8 * LONGSIZE)(\dst) 34 LONG_S \val, (\offset + 9 * LONGSIZE)(\dst) 35 LONG_S \val, (\offset + 10 * LONGSIZE)(\dst) 36 LONG_S \val, (\offset + 11 * LONGSIZE)(\dst) 37 LONG_S \val, (\offset + 12 * LONGSIZE)(\dst) 38 LONG_S \val, (\offset + 13 * LONGSIZE)(\dst) 39 LONG_S \val, (\offset + 14 * LONGSIZE)(\dst) 40 LONG_S \val, (\offset + 15 * LONGSIZE)(\dst) 41#endif 42 .endm 43 44 .macro cache_loop curr, end, line_sz, op 4510: cache \op, 0(\curr) 46 PTR_ADDU \curr, \curr, \line_sz 47 bne \curr, \end, 10b 48 .endm 49 50 .macro l1_info sz, line_sz, off 51 .set push 52 .set noat 53 54 mfc0 $1, CP0_CONFIG, 1 55 56 /* detect line size */ 57 srl \line_sz, $1, \off + MIPS_CONF1_DL_SHF - MIPS_CONF1_DA_SHF 58 andi \line_sz, \line_sz, (MIPS_CONF1_DL >> MIPS_CONF1_DL_SHF) 59 move \sz, zero 60 beqz \line_sz, 10f 61 li \sz, 2 62 sllv \line_sz, \sz, \line_sz 63 64 /* detect associativity */ 65 srl \sz, $1, \off + MIPS_CONF1_DA_SHF - MIPS_CONF1_DA_SHF 66 andi \sz, \sz, (MIPS_CONF1_DA >> MIPS_CONF1_DA_SHF) 67 addiu \sz, \sz, 1 68 69 /* sz *= line_sz */ 70 mul \sz, \sz, \line_sz 71 72 /* detect log32(sets) */ 73 srl $1, $1, \off + MIPS_CONF1_DS_SHF - MIPS_CONF1_DA_SHF 74 andi $1, $1, (MIPS_CONF1_DS >> MIPS_CONF1_DS_SHF) 75 addiu $1, $1, 1 76 andi $1, $1, 0x7 77 78 /* sz <<= log32(sets) */ 79 sllv \sz, \sz, $1 80 81 /* sz *= 32 */ 82 li $1, 32 83 mul \sz, \sz, $1 8410: 85 .set pop 86 .endm 87/* 88 * mips_cache_reset - low level initialisation of the primary caches 89 * 90 * This routine initialises the primary caches to ensure that they have good 91 * parity. It must be called by the ROM before any cached locations are used 92 * to prevent the possibility of data with bad parity being written to memory. 93 * 94 * To initialise the instruction cache it is essential that a source of data 95 * with good parity is available. This routine will initialise an area of 96 * memory starting at location zero to be used as a source of parity. 97 * 98 * RETURNS: N/A 99 * 100 */ 101LEAF(mips_cache_reset) 102#ifndef CONFIG_SYS_CACHE_SIZE_AUTO 103 li t2, CONFIG_SYS_ICACHE_SIZE 104 li t8, CONFIG_SYS_ICACHE_LINE_SIZE 105#else 106 l1_info t2, t8, MIPS_CONF1_IA_SHF 107#endif 108 109#ifndef CONFIG_SYS_CACHE_SIZE_AUTO 110 li t3, CONFIG_SYS_DCACHE_SIZE 111 li t9, CONFIG_SYS_DCACHE_LINE_SIZE 112#else 113 l1_info t3, t9, MIPS_CONF1_DA_SHF 114#endif 115 116#ifdef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD 117 118 /* Determine the largest L1 cache size */ 119#ifndef CONFIG_SYS_CACHE_SIZE_AUTO 120#if CONFIG_SYS_ICACHE_SIZE > CONFIG_SYS_DCACHE_SIZE 121 li v0, CONFIG_SYS_ICACHE_SIZE 122#else 123 li v0, CONFIG_SYS_DCACHE_SIZE 124#endif 125#else 126 move v0, t2 127 sltu t1, t2, t3 128 movn v0, t3, t1 129#endif 130 /* 131 * Now clear that much memory starting from zero. 132 */ 133 PTR_LI a0, CKSEG1 134 PTR_ADDU a1, a0, v0 1352: PTR_ADDIU a0, 64 136 f_fill64 a0, -64, zero 137 bne a0, a1, 2b 138 139#endif /* CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD */ 140 141 /* 142 * The TagLo registers used depend upon the CPU implementation, but the 143 * architecture requires that it is safe for software to write to both 144 * TagLo selects 0 & 2 covering supported cases. 145 */ 146 mtc0 zero, CP0_TAGLO 147 mtc0 zero, CP0_TAGLO, 2 148 149 /* 150 * The caches are probably in an indeterminate state, so we force good 151 * parity into them by doing an invalidate for each line. If 152 * CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD is set then we'll proceed to 153 * perform a load/fill & a further invalidate for each line, assuming 154 * that the bottom of RAM (having just been cleared) will generate good 155 * parity for the cache. 156 */ 157 158 /* 159 * Initialize the I-cache first, 160 */ 161 blez t2, 1f 162 PTR_LI t0, INDEX_BASE 163 PTR_ADDU t1, t0, t2 164 /* clear tag to invalidate */ 165 cache_loop t0, t1, t8, INDEX_STORE_TAG_I 166#ifdef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD 167 /* fill once, so data field parity is correct */ 168 PTR_LI t0, INDEX_BASE 169 cache_loop t0, t1, t8, FILL 170 /* invalidate again - prudent but not strictly neccessary */ 171 PTR_LI t0, INDEX_BASE 172 cache_loop t0, t1, t8, INDEX_STORE_TAG_I 173#endif 174 175 /* 176 * then initialize D-cache. 177 */ 1781: blez t3, 3f 179 PTR_LI t0, INDEX_BASE 180 PTR_ADDU t1, t0, t3 181 /* clear all tags */ 182 cache_loop t0, t1, t9, INDEX_STORE_TAG_D 183#ifdef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD 184 /* load from each line (in cached space) */ 185 PTR_LI t0, INDEX_BASE 1862: LONG_L zero, 0(t0) 187 PTR_ADDU t0, t9 188 bne t0, t1, 2b 189 /* clear all tags */ 190 PTR_LI t0, INDEX_BASE 191 cache_loop t0, t1, t9, INDEX_STORE_TAG_D 192#endif 193 1943: jr ra 195 END(mips_cache_reset) 196 197/* 198 * dcache_status - get cache status 199 * 200 * RETURNS: 0 - cache disabled; 1 - cache enabled 201 * 202 */ 203LEAF(dcache_status) 204 mfc0 t0, CP0_CONFIG 205 li t1, CONF_CM_UNCACHED 206 andi t0, t0, CONF_CM_CMASK 207 move v0, zero 208 beq t0, t1, 2f 209 li v0, 1 2102: jr ra 211 END(dcache_status) 212 213/* 214 * dcache_disable - disable cache 215 * 216 * RETURNS: N/A 217 * 218 */ 219LEAF(dcache_disable) 220 mfc0 t0, CP0_CONFIG 221 li t1, -8 222 and t0, t0, t1 223 ori t0, t0, CONF_CM_UNCACHED 224 mtc0 t0, CP0_CONFIG 225 jr ra 226 END(dcache_disable) 227 228/* 229 * dcache_enable - enable cache 230 * 231 * RETURNS: N/A 232 * 233 */ 234LEAF(dcache_enable) 235 mfc0 t0, CP0_CONFIG 236 ori t0, CONF_CM_CMASK 237 xori t0, CONF_CM_CMASK 238 ori t0, CONFIG_SYS_MIPS_CACHE_MODE 239 mtc0 t0, CP0_CONFIG 240 jr ra 241 END(dcache_enable) 242