arch/mips/sibyte/common/bus_watcher.c

   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 <linux/seq_file.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 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
  41 #include <asm/sibyte/bcm1480_regs.h>
  42 #endif
  43
  44
  45 struct bw_stats_struct {
  46         uint64_t status;
  47         uint32_t l2_err;
  48         uint32_t memio_err;
  49         int status_printed;
  50         unsigned long l2_cor_d;
  51         unsigned long l2_bad_d;
  52         unsigned long l2_cor_t;
  53         unsigned long l2_bad_t;
  54         unsigned long mem_cor_d;
  55         unsigned long mem_bad_d;
  56         unsigned long bus_error;
  57 } bw_stats;
  58
  59
  60 static void print_summary(uint32_t status, uint32_t l2_err,
  61                           uint32_t memio_err)
  62 {
  63         printk("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
  64         printk("\nLast recorded signature:\n");
  65         printk("Request %02x from %d, answered by %d with Dcode %d\n",
  66                (unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
  67                (int)(G_SCD_BERR_TID(status) >> 6),
  68                (int)G_SCD_BERR_RID(status),
  69                (int)G_SCD_BERR_DCODE(status));
  70 }
  71
  72 /*
  73  * check_bus_watcher is exported for use in situations where we want
  74  * to see the most recent status of the bus watcher, which might have
  75  * already been destructively read out of the registers.
  76  *
  77  * notes: this is currently used by the cache error handler
  78  *        should provide locking against the interrupt handler
  79  */
  80 void check_bus_watcher(void)
  81 {
  82         u32 status, l2_err, memio_err;
  83
  84 #if defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
  85         /* Use non-destructive register */
  86         status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG));
  87 #elif defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
  88         /* Use non-destructive register */
  89         /* Same as 1250 except BUS_ERR_STATUS_DEBUG is in a different place. */
  90         status = csr_in32(IOADDR(A_BCM1480_BUS_ERR_STATUS_DEBUG));
  91 #else
  92 #error bus watcher being built for unknown Sibyte SOC!
  93 #endif
  94         if (!(status & 0x7fffffff)) {
  95                 printk("Using last values reaped by bus watcher driver\n");
  96                 status = bw_stats.status;
  97                 l2_err = bw_stats.l2_err;
  98                 memio_err = bw_stats.memio_err;
  99         } else {
 100                 l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
 101                 memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
 102         }
 103         if (status & ~(1UL << 31))
 104                 print_summary(status, l2_err, memio_err);
 105         else
 106                 printk("Bus watcher indicates no error\n");
 107 }
 108
 109 #ifdef CONFIG_PROC_FS
 110
 111 /* For simplicity, I want to assume a single read is required each
 112    time */
 113 static int bw_proc_show(struct seq_file *m, void *v)
 114 {
 115         struct bw_stats_struct *stats = m->private;
 116
 117         seq_puts(m, "SiByte Bus Watcher statistics\n");
 118         seq_puts(m, "-----------------------------\n");
 119         seq_printf(m, "L2-d-cor %8ld\nL2-d-bad %8ld\n",
 120                    stats->l2_cor_d, stats->l2_bad_d);
 121         seq_printf(m, "L2-t-cor %8ld\nL2-t-bad %8ld\n",
 122                    stats->l2_cor_t, stats->l2_bad_t);
 123         seq_printf(m, "MC-d-cor %8ld\nMC-d-bad %8ld\n",
 124                    stats->mem_cor_d, stats->mem_bad_d);
 125         seq_printf(m, "IO-err   %8ld\n", stats->bus_error);
 126         seq_puts(m, "\nLast recorded signature:\n");
 127         seq_printf(m, "Request %02x from %d, answered by %d with Dcode %d\n",
 128                    (unsigned int)(G_SCD_BERR_TID(stats->status) & 0x3f),
 129                    (int)(G_SCD_BERR_TID(stats->status) >> 6),
 130                    (int)G_SCD_BERR_RID(stats->status),
 131                    (int)G_SCD_BERR_DCODE(stats->status));
 132         /* XXXKW indicate multiple errors between printings, or stats
 133            collection (or both)? */
 134         if (stats->status & M_SCD_BERR_MULTERRS)
 135                 seq_puts(m, "Multiple errors observed since last check.\n");
 136         if (stats->status_printed) {
 137                 seq_puts(m, "(no change since last printing)\n");
 138         } else {
 139                 stats->status_printed = 1;
 140         }
 141
 142         return 0;
 143 }
 144
 145 static void create_proc_decoder(struct bw_stats_struct *stats)
 146 {
 147         struct proc_dir_entry *ent;
 148
 149         ent = proc_create_single_data("bus_watcher", S_IWUSR | S_IRUGO, NULL,
 150                         bw_proc_show, stats);
 151         if (!ent) {
 152                 printk(KERN_INFO "Unable to initialize bus_watcher /proc entry\n");
 153                 return;
 154         }
 155 }
 156
 157 #endif /* CONFIG_PROC_FS */
 158
 159 /*
 160  * sibyte_bw_int - handle bus watcher interrupts and accumulate counts
 161  *
 162  * notes: possible re-entry due to multiple sources
 163  *        should check/indicate saturation
 164  */
 165 static irqreturn_t sibyte_bw_int(int irq, void *data)
 166 {
 167         struct bw_stats_struct *stats = data;
 168         unsigned long cntr;
 169 #ifdef CONFIG_SIBYTE_BW_TRACE
 170         int i;
 171 #endif
 172
 173 #ifdef CONFIG_SIBYTE_BW_TRACE
 174         csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG));
 175         csr_out32(M_SCD_TRACE_CFG_START_READ, IOADDR(A_SCD_TRACE_CFG));
 176
 177         for (i=0; i<256*6; i++)
 178                 printk("%016llx\n",
 179                        (long long)__raw_readq(IOADDR(A_SCD_TRACE_READ)));
 180
 181         csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
 182         csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
 183 #endif
 184
 185         /* Destructive read, clears register and interrupt */
 186         stats->status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
 187         stats->status_printed = 0;
 188
 189         stats->l2_err = cntr = csr_in32(IOADDR(A_BUS_L2_ERRORS));
 190         stats->l2_cor_d += G_SCD_L2ECC_CORR_D(cntr);
 191         stats->l2_bad_d += G_SCD_L2ECC_BAD_D(cntr);
 192         stats->l2_cor_t += G_SCD_L2ECC_CORR_T(cntr);
 193         stats->l2_bad_t += G_SCD_L2ECC_BAD_T(cntr);
 194         csr_out32(0, IOADDR(A_BUS_L2_ERRORS));
 195
 196         stats->memio_err = cntr = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
 197         stats->mem_cor_d += G_SCD_MEM_ECC_CORR(cntr);
 198         stats->mem_bad_d += G_SCD_MEM_ECC_BAD(cntr);
 199         stats->bus_error += G_SCD_MEM_BUSERR(cntr);
 200         csr_out32(0, IOADDR(A_BUS_MEM_IO_ERRORS));
 201
 202         return IRQ_HANDLED;
 203 }
 204
 205 int __init sibyte_bus_watcher(void)
 206 {
 207         memset(&bw_stats, 0, sizeof(struct bw_stats_struct));
 208         bw_stats.status_printed = 1;
 209
 210         if (request_irq(K_INT_BAD_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 211                 printk("Failed to register bus watcher BAD_ECC irq\n");
 212                 return -1;
 213         }
 214         if (request_irq(K_INT_COR_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 215                 free_irq(K_INT_BAD_ECC, &bw_stats);
 216                 printk("Failed to register bus watcher COR_ECC irq\n");
 217                 return -1;
 218         }
 219         if (request_irq(K_INT_IO_BUS, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 220                 free_irq(K_INT_BAD_ECC, &bw_stats);
 221                 free_irq(K_INT_COR_ECC, &bw_stats);
 222                 printk("Failed to register bus watcher IO_BUS irq\n");
 223                 return -1;
 224         }
 225
 226 #ifdef CONFIG_PROC_FS
 227         create_proc_decoder(&bw_stats);
 228 #endif
 229
 230 #ifdef CONFIG_SIBYTE_BW_TRACE
 231         csr_out32((M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
 232                    K_SCD_TRSEQ_TRIGGER_ALL),
 233                   IOADDR(A_SCD_TRACE_SEQUENCE_0));
 234         csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
 235         csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
 236 #endif
 237
 238         return 0;
 239 }
 240
 241 device_initcall(sibyte_bus_watcher);