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 #ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
  85         /* Destructive read, clears register and interrupt */
  86         status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
  87 #elif defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
  88         /* Use non-destructive register */
  89         status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG));
  90 #elif defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
  91         /* Use non-destructive register */
  92         /* Same as 1250 except BUS_ERR_STATUS_DEBUG is in a different place. */
  93         status = csr_in32(IOADDR(A_BCM1480_BUS_ERR_STATUS_DEBUG));
  94 #else
  95 #error bus watcher being built for unknown Sibyte SOC!
  96 #endif
  97         if (!(status & 0x7fffffff)) {
  98                 printk("Using last values reaped by bus watcher driver\n");
  99                 status = bw_stats.status;
 100                 l2_err = bw_stats.l2_err;
 101                 memio_err = bw_stats.memio_err;
 102         } else {
 103                 l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
 104                 memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
 105         }
 106         if (status & ~(1UL << 31))
 107                 print_summary(status, l2_err, memio_err);
 108         else
 109                 printk("Bus watcher indicates no error\n");
 110 }
 111
 112 #ifdef CONFIG_PROC_FS
 113
 114 /* For simplicity, I want to assume a single read is required each
 115    time */
 116 static int bw_proc_show(struct seq_file *m, void *v)
 117 {
 118         struct bw_stats_struct *stats = m->private;
 119
 120         seq_puts(m, "SiByte Bus Watcher statistics\n");
 121         seq_puts(m, "-----------------------------\n");
 122         seq_printf(m, "L2-d-cor %8ld\nL2-d-bad %8ld\n",
 123                    stats->l2_cor_d, stats->l2_bad_d);
 124         seq_printf(m, "L2-t-cor %8ld\nL2-t-bad %8ld\n",
 125                    stats->l2_cor_t, stats->l2_bad_t);
 126         seq_printf(m, "MC-d-cor %8ld\nMC-d-bad %8ld\n",
 127                    stats->mem_cor_d, stats->mem_bad_d);
 128         seq_printf(m, "IO-err   %8ld\n", stats->bus_error);
 129         seq_puts(m, "\nLast recorded signature:\n");
 130         seq_printf(m, "Request %02x from %d, answered by %d with Dcode %d\n",
 131                    (unsigned int)(G_SCD_BERR_TID(stats->status) & 0x3f),
 132                    (int)(G_SCD_BERR_TID(stats->status) >> 6),
 133                    (int)G_SCD_BERR_RID(stats->status),
 134                    (int)G_SCD_BERR_DCODE(stats->status));
 135         /* XXXKW indicate multiple errors between printings, or stats
 136            collection (or both)? */
 137         if (stats->status & M_SCD_BERR_MULTERRS)
 138                 seq_puts(m, "Multiple errors observed since last check.\n");
 139         if (stats->status_printed) {
 140                 seq_puts(m, "(no change since last printing)\n");
 141         } else {
 142                 stats->status_printed = 1;
 143         }
 144
 145         return 0;
 146 }
 147
 148 static int bw_proc_open(struct inode *inode, struct file *file)
 149 {
 150         return single_open(file, bw_proc_show, PDE_DATA(inode));
 151 }
 152
 153 static const struct file_operations bw_proc_fops = {
 154         .open           = bw_proc_open,
 155         .read           = seq_read,
 156         .llseek         = seq_lseek,
 157         .release        = single_release,
 158 };
 159
 160 static void create_proc_decoder(struct bw_stats_struct *stats)
 161 {
 162         struct proc_dir_entry *ent;
 163
 164         ent = proc_create_data("bus_watcher", S_IWUSR | S_IRUGO, NULL,
 165                                &bw_proc_fops, stats);
 166         if (!ent) {
 167                 printk(KERN_INFO "Unable to initialize bus_watcher /proc entry\n");
 168                 return;
 169         }
 170 }
 171
 172 #endif /* CONFIG_PROC_FS */
 173
 174 /*
 175  * sibyte_bw_int - handle bus watcher interrupts and accumulate counts
 176  *
 177  * notes: possible re-entry due to multiple sources
 178  *        should check/indicate saturation
 179  */
 180 static irqreturn_t sibyte_bw_int(int irq, void *data)
 181 {
 182         struct bw_stats_struct *stats = data;
 183         unsigned long cntr;
 184 #ifdef CONFIG_SIBYTE_BW_TRACE
 185         int i;
 186 #endif
 187
 188 #ifdef CONFIG_SIBYTE_BW_TRACE
 189         csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG));
 190         csr_out32(M_SCD_TRACE_CFG_START_READ, IOADDR(A_SCD_TRACE_CFG));
 191
 192         for (i=0; i<256*6; i++)
 193                 printk("%016llx\n",
 194                        (long long)__raw_readq(IOADDR(A_SCD_TRACE_READ)));
 195
 196         csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
 197         csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
 198 #endif
 199
 200         /* Destructive read, clears register and interrupt */
 201         stats->status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
 202         stats->status_printed = 0;
 203
 204         stats->l2_err = cntr = csr_in32(IOADDR(A_BUS_L2_ERRORS));
 205         stats->l2_cor_d += G_SCD_L2ECC_CORR_D(cntr);
 206         stats->l2_bad_d += G_SCD_L2ECC_BAD_D(cntr);
 207         stats->l2_cor_t += G_SCD_L2ECC_CORR_T(cntr);
 208         stats->l2_bad_t += G_SCD_L2ECC_BAD_T(cntr);
 209         csr_out32(0, IOADDR(A_BUS_L2_ERRORS));
 210
 211         stats->memio_err = cntr = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
 212         stats->mem_cor_d += G_SCD_MEM_ECC_CORR(cntr);
 213         stats->mem_bad_d += G_SCD_MEM_ECC_BAD(cntr);
 214         stats->bus_error += G_SCD_MEM_BUSERR(cntr);
 215         csr_out32(0, IOADDR(A_BUS_MEM_IO_ERRORS));
 216
 217         return IRQ_HANDLED;
 218 }
 219
 220 int __init sibyte_bus_watcher(void)
 221 {
 222         memset(&bw_stats, 0, sizeof(struct bw_stats_struct));
 223         bw_stats.status_printed = 1;
 224
 225         if (request_irq(K_INT_BAD_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 226                 printk("Failed to register bus watcher BAD_ECC irq\n");
 227                 return -1;
 228         }
 229         if (request_irq(K_INT_COR_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 230                 free_irq(K_INT_BAD_ECC, &bw_stats);
 231                 printk("Failed to register bus watcher COR_ECC irq\n");
 232                 return -1;
 233         }
 234         if (request_irq(K_INT_IO_BUS, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
 235                 free_irq(K_INT_BAD_ECC, &bw_stats);
 236                 free_irq(K_INT_COR_ECC, &bw_stats);
 237                 printk("Failed to register bus watcher IO_BUS irq\n");
 238                 return -1;
 239         }
 240
 241 #ifdef CONFIG_PROC_FS
 242         create_proc_decoder(&bw_stats);
 243 #endif
 244
 245 #ifdef CONFIG_SIBYTE_BW_TRACE
 246         csr_out32((M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
 247                    K_SCD_TRSEQ_TRIGGER_ALL),
 248                   IOADDR(A_SCD_TRACE_SEQUENCE_0));
 249         csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
 250         csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
 251 #endif
 252
 253         return 0;
 254 }
 255
 256 __initcall(sibyte_bus_watcher);