1/* 2 * Copyright (C) 2002,2003 Broadcom Corporation 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 */ 18 19/* 20 * The Bus Watcher monitors internal bus transactions and maintains 21 * counts of transactions with error status, logging details and 22 * causing one of several interrupts. This driver provides a handler 23 * for those interrupts which aggregates the counts (to avoid 24 * saturating the 8-bit counters) and provides a presence in 25 * /proc/bus_watcher if PROC_FS is on. 26 */ 27 28#include <linux/init.h> 29#include <linux/kernel.h> 30#include <linux/interrupt.h> 31#include <linux/sched.h> 32#include <linux/proc_fs.h> 33#include <asm/system.h> 34#include <asm/io.h> 35 36#include <asm/sibyte/sb1250.h> 37#include <asm/sibyte/sb1250_regs.h> 38#include <asm/sibyte/sb1250_int.h> 39#include <asm/sibyte/sb1250_scd.h> 40 41 42struct bw_stats_struct { 43 uint64_t status; 44 uint32_t l2_err; 45 uint32_t memio_err; 46 int status_printed; 47 unsigned long l2_cor_d; 48 unsigned long l2_bad_d; 49 unsigned long l2_cor_t; 50 unsigned long l2_bad_t; 51 unsigned long mem_cor_d; 52 unsigned long mem_bad_d; 53 unsigned long bus_error; 54} bw_stats; 55 56 57static void print_summary(uint32_t status, uint32_t l2_err, 58 uint32_t memio_err) 59{ 60 printk("Bus watcher error counters: %08x %08x\n", l2_err, memio_err); 61 printk("\nLast recorded signature:\n"); 62 printk("Request %02x from %d, answered by %d with Dcode %d\n", 63 (unsigned int)(G_SCD_BERR_TID(status) & 0x3f), 64 (int)(G_SCD_BERR_TID(status) >> 6), 65 (int)G_SCD_BERR_RID(status), 66 (int)G_SCD_BERR_DCODE(status)); 67} 68 69/* 70 * check_bus_watcher is exported for use in situations where we want 71 * to see the most recent status of the bus watcher, which might have 72 * already been destructively read out of the registers. 73 * 74 * notes: this is currently used by the cache error handler 75 * should provide locking against the interrupt handler 76 */ 77void check_bus_watcher(void) 78{ 79 u32 status, l2_err, memio_err; 80 81#ifdef CONFIG_SB1_PASS_1_WORKAROUNDS 82 /* Destructive read, clears register and interrupt */ 83 status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS)); 84#else 85 /* Use non-destructive register */ 86 status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG)); 87#endif 88 if (!(status & 0x7fffffff)) { 89 printk("Using last values reaped by bus watcher driver\n"); 90 status = bw_stats.status; 91 l2_err = bw_stats.l2_err; 92 memio_err = bw_stats.memio_err; 93 } else { 94 l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS)); 95 memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS)); 96 } 97 if (status & ~(1UL << 31)) 98 print_summary(status, l2_err, memio_err); 99 else 100 printk("Bus watcher indicates no error\n"); 101} 102 103static int bw_print_buffer(char *page, struct bw_stats_struct *stats) 104{ 105 int len; 106 107 len = sprintf(page, "SiByte Bus Watcher statistics\n"); 108 len += sprintf(page+len, "-----------------------------\n"); 109 len += sprintf(page+len, "L2-d-cor %8ld\nL2-d-bad %8ld\n", 110 stats->l2_cor_d, stats->l2_bad_d); 111 len += sprintf(page+len, "L2-t-cor %8ld\nL2-t-bad %8ld\n", 112 stats->l2_cor_t, stats->l2_bad_t); 113 len += sprintf(page+len, "MC-d-cor %8ld\nMC-d-bad %8ld\n", 114 stats->mem_cor_d, stats->mem_bad_d); 115 len += sprintf(page+len, "IO-err %8ld\n", stats->bus_error); 116 len += sprintf(page+len, "\nLast recorded signature:\n"); 117 len += sprintf(page+len, "Request %02x from %d, answered by %d with Dcode %d\n", 118 (unsigned int)(G_SCD_BERR_TID(stats->status) & 0x3f), 119 (int)(G_SCD_BERR_TID(stats->status) >> 6), 120 (int)G_SCD_BERR_RID(stats->status), 121 (int)G_SCD_BERR_DCODE(stats->status)); 122 /* XXXKW indicate multiple errors between printings, or stats 123 collection (or both)? */ 124 if (stats->status & M_SCD_BERR_MULTERRS) 125 len += sprintf(page+len, "Multiple errors observed since last check.\n"); 126 if (stats->status_printed) { 127 len += sprintf(page+len, "(no change since last printing)\n"); 128 } else { 129 stats->status_printed = 1; 130 } 131 132 return len; 133} 134 135#ifdef CONFIG_PROC_FS 136 137/* For simplicity, I want to assume a single read is required each 138 time */ 139static int bw_read_proc(char *page, char **start, off_t off, 140 int count, int *eof, void *data) 141{ 142 int len; 143 144 if (off == 0) { 145 len = bw_print_buffer(page, data); 146 *start = page; 147 } else { 148 len = 0; 149 *eof = 1; 150 } 151 return len; 152} 153 154static void create_proc_decoder(struct bw_stats_struct *stats) 155{ 156 struct proc_dir_entry *ent; 157 158 ent = create_proc_read_entry("bus_watcher", S_IWUSR | S_IRUGO, NULL, 159 bw_read_proc, stats); 160 if (!ent) { 161 printk(KERN_INFO "Unable to initialize bus_watcher /proc entry\n"); 162 return; 163 } 164} 165 166#endif /* CONFIG_PROC_FS */ 167 168/* 169 * sibyte_bw_int - handle bus watcher interrupts and accumulate counts 170 * 171 * notes: possible re-entry due to multiple sources 172 * should check/indicate saturation 173 */ 174static irqreturn_t sibyte_bw_int(int irq, void *data) 175{ 176 struct bw_stats_struct *stats = data; 177 unsigned long cntr; 178#ifdef CONFIG_SIBYTE_BW_TRACE 179 int i; 180#endif 181#ifndef CONFIG_PROC_FS 182 char bw_buf[1024]; 183#endif 184 185#ifdef CONFIG_SIBYTE_BW_TRACE 186 csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG)); 187 csr_out32(M_SCD_TRACE_CFG_START_READ, IOADDR(A_SCD_TRACE_CFG)); 188 189 for (i=0; i<256*6; i++) 190 printk("%016llx\n", 191 (long long)__raw_readq(IOADDR(A_SCD_TRACE_READ))); 192 193 csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG)); 194 csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG)); 195#endif 196 197 /* Destructive read, clears register and interrupt */ 198 stats->status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS)); 199 stats->status_printed = 0; 200 201 stats->l2_err = cntr = csr_in32(IOADDR(A_BUS_L2_ERRORS)); 202 stats->l2_cor_d += G_SCD_L2ECC_CORR_D(cntr); 203 stats->l2_bad_d += G_SCD_L2ECC_BAD_D(cntr); 204 stats->l2_cor_t += G_SCD_L2ECC_CORR_T(cntr); 205 stats->l2_bad_t += G_SCD_L2ECC_BAD_T(cntr); 206 csr_out32(0, IOADDR(A_BUS_L2_ERRORS)); 207 208 stats->memio_err = cntr = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS)); 209 stats->mem_cor_d += G_SCD_MEM_ECC_CORR(cntr); 210 stats->mem_bad_d += G_SCD_MEM_ECC_BAD(cntr); 211 stats->bus_error += G_SCD_MEM_BUSERR(cntr); 212 csr_out32(0, IOADDR(A_BUS_MEM_IO_ERRORS)); 213 214#ifndef CONFIG_PROC_FS 215 bw_print_buffer(bw_buf, stats); 216 printk(bw_buf); 217#endif 218 219 return IRQ_HANDLED; 220} 221 222int __init sibyte_bus_watcher(void) 223{ 224 memset(&bw_stats, 0, sizeof(struct bw_stats_struct)); 225 bw_stats.status_printed = 1; 226 227 if (request_irq(K_INT_BAD_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) { 228 printk("Failed to register bus watcher BAD_ECC irq\n"); 229 return -1; 230 } 231 if (request_irq(K_INT_COR_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) { 232 free_irq(K_INT_BAD_ECC, &bw_stats); 233 printk("Failed to register bus watcher COR_ECC irq\n"); 234 return -1; 235 } 236 if (request_irq(K_INT_IO_BUS, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) { 237 free_irq(K_INT_BAD_ECC, &bw_stats); 238 free_irq(K_INT_COR_ECC, &bw_stats); 239 printk("Failed to register bus watcher IO_BUS irq\n"); 240 return -1; 241 } 242 243#ifdef CONFIG_PROC_FS 244 create_proc_decoder(&bw_stats); 245#endif 246 247#ifdef CONFIG_SIBYTE_BW_TRACE 248 csr_out32((M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE | 249 K_SCD_TRSEQ_TRIGGER_ALL), 250 IOADDR(A_SCD_TRACE_SEQUENCE_0)); 251 csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG)); 252 csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG)); 253#endif 254 255 return 0; 256} 257 258__initcall(sibyte_bus_watcher); 259