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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 | /* * Copyright (C) 2001,2002,2003 Broadcom Corporation * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <linux/init.h> #include <asm/asm.h> #include <asm/regdef.h> #include <asm/mipsregs.h> #include <asm/stackframe.h> #include <asm/cacheops.h> #include <asm/sibyte/board.h> #define C0_ERRCTL $26 /* CP0: Error info */ #define C0_CERR_I $27 /* CP0: Icache error */ #define C0_CERR_D $27,1 /* CP0: Dcache error */ /* * Based on SiByte sample software cache-err/cerr.S * CVS revision 1.8. Only the 'unrecoverable' case * is changed. */ .set mips64 .set noreorder .set noat /* * sb1_cerr_vec: code to be copied to the Cache Error * Exception vector. The code must be pushed out to memory * (either by copying to Kseg0 and Kseg1 both, or by flushing * the L1 and L2) since it is fetched as 0xa0000100. * * NOTE: Be sure this handler is at most 28 instructions long * since the final 16 bytes of the exception vector memory * (0x170-0x17f) are used to preserve k0, k1, and ra. */ LEAF(except_vec2_sb1) /* * If this error is recoverable, we need to exit the handler * without having dirtied any registers. To do this, * save/restore k0 and k1 from low memory (Useg is direct * mapped while ERL=1). Note that we can't save to a * CPU-specific location without ruining a register in the * process. This means we are vulnerable to data corruption * whenever the handler is reentered by a second CPU. */ sd k0,0x170($0) sd k1,0x178($0) #ifdef CONFIG_SB1_CEX_ALWAYS_FATAL j handle_vec2_sb1 nop #else /* * M_ERRCTL_RECOVERABLE is bit 31, which makes it easy to tell * if we can fast-path out of here for a h/w-recovered error. */ mfc0 k1,C0_ERRCTL bgtz k1,attempt_recovery sll k0,k1,1 recovered_dcache: /* * Unlock CacheErr-D (which in turn unlocks CacheErr-DPA). * Ought to log the occurrence of this recovered dcache error. */ b recovered mtc0 $0,C0_CERR_D attempt_recovery: /* * k0 has C0_ERRCTL << 1, which puts 'DC' at bit 31. Any * Dcache errors we can recover from will take more extensive * processing. For now, they are considered "unrecoverable". * Note that 'DC' becoming set (outside of ERL mode) will * cause 'IC' to clear; so if there's an Icache error, we'll * only find out about it if we recover from this error and * continue executing. */ bltz k0,unrecoverable sll k0,1 /* * k0 has C0_ERRCTL << 2, which puts 'IC' at bit 31. If an * Icache error isn't indicated, I'm not sure why we got here. * Consider that case "unrecoverable" for now. */ bgez k0,unrecoverable attempt_icache_recovery: /* * External icache errors are due to uncorrectable ECC errors * in the L2 cache or Memory Controller and cannot be * recovered here. */ mfc0 k0,C0_CERR_I /* delay slot */ li k1,1 << 26 /* ICACHE_EXTERNAL */ and k1,k0 bnez k1,unrecoverable andi k0,0x1fe0 /* * Since the error is internal, the 'IDX' field from * CacheErr-I is valid and we can just invalidate all blocks * in that set. */ cache Index_Invalidate_I,(0<<13)(k0) cache Index_Invalidate_I,(1<<13)(k0) cache Index_Invalidate_I,(2<<13)(k0) cache Index_Invalidate_I,(3<<13)(k0) /* Ought to log this recovered icache error */ recovered: /* Restore the saved registers */ ld k0,0x170($0) ld k1,0x178($0) eret unrecoverable: /* Unrecoverable Icache or Dcache error; log it and/or fail */ j handle_vec2_sb1 nop #endif END(except_vec2_sb1) LEAF(handle_vec2_sb1) mfc0 k0,CP0_CONFIG li k1,~CONF_CM_CMASK and k0,k0,k1 ori k0,k0,CONF_CM_UNCACHED mtc0 k0,CP0_CONFIG SSNOP SSNOP SSNOP SSNOP bnezl $0, 1f 1: mfc0 k0, CP0_STATUS sll k0, k0, 3 # check CU0 (kernel?) bltz k0, 2f nop /* Get a valid Kseg0 stack pointer. Any task's stack pointer * will do, although if we ever want to resume execution we * better not have corrupted any state. */ get_saved_sp move sp, k1 2: j sb1_cache_error nop END(handle_vec2_sb1) |