arch/mips/sgi-ip22/ip22-berr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ip22-berr.c: Bus error handling.
   4  *
   5  * Copyright (C) 2002, 2003 Ladislav Michl (ladis@linux-mips.org)
   6  */
   7
   8 #include <linux/init.h>
   9 #include <linux/kernel.h>
  10 #include <linux/sched/signal.h>
  11
  12 #include <asm/addrspace.h>
  13 #include <asm/traps.h>
  14 #include <asm/branch.h>
  15 #include <asm/irq_regs.h>
  16 #include <asm/sgi/mc.h>
  17 #include <asm/sgi/hpc3.h>
  18 #include <asm/sgi/ioc.h>
  19 #include <asm/sgi/ip22.h>
  20
  21
  22 static unsigned int cpu_err_stat;       /* Status reg for CPU */
  23 static unsigned int gio_err_stat;       /* Status reg for GIO */
  24 static unsigned int cpu_err_addr;       /* Error address reg for CPU */
  25 static unsigned int gio_err_addr;       /* Error address reg for GIO */
  26 static unsigned int extio_stat;
  27 static unsigned int hpc3_berr_stat;     /* Bus error interrupt status */
  28
  29 static void save_and_clear_buserr(void)
  30 {
  31         /* save status registers */
  32         cpu_err_addr = sgimc->cerr;
  33         cpu_err_stat = sgimc->cstat;
  34         gio_err_addr = sgimc->gerr;
  35         gio_err_stat = sgimc->gstat;
  36         extio_stat = ip22_is_fullhouse() ? sgioc->extio : (sgint->errstat << 4);
  37         hpc3_berr_stat = hpc3c0->bestat;
  38
  39         sgimc->cstat = sgimc->gstat = 0;
  40 }
  41
  42 #define GIO_ERRMASK     0xff00
  43 #define CPU_ERRMASK     0x3f00
  44
  45 static void print_buserr(void)
  46 {
  47         if (extio_stat & EXTIO_MC_BUSERR)
  48                 printk(KERN_ERR "MC Bus Error\n");
  49         if (extio_stat & EXTIO_HPC3_BUSERR)
  50                 printk(KERN_ERR "HPC3 Bus Error 0x%x:<id=0x%x,%s,lane=0x%x>\n",
  51                         hpc3_berr_stat,
  52                         (hpc3_berr_stat & HPC3_BESTAT_PIDMASK) >>
  53                                           HPC3_BESTAT_PIDSHIFT,
  54                         (hpc3_berr_stat & HPC3_BESTAT_CTYPE) ? "PIO" : "DMA",
  55                         hpc3_berr_stat & HPC3_BESTAT_BLMASK);
  56         if (extio_stat & EXTIO_EISA_BUSERR)
  57                 printk(KERN_ERR "EISA Bus Error\n");
  58         if (cpu_err_stat & CPU_ERRMASK)
  59                 printk(KERN_ERR "CPU error 0x%x<%s%s%s%s%s%s> @ 0x%08x\n",
  60                         cpu_err_stat,
  61                         cpu_err_stat & SGIMC_CSTAT_RD ? "RD " : "",
  62                         cpu_err_stat & SGIMC_CSTAT_PAR ? "PAR " : "",
  63                         cpu_err_stat & SGIMC_CSTAT_ADDR ? "ADDR " : "",
  64                         cpu_err_stat & SGIMC_CSTAT_SYSAD_PAR ? "SYSAD " : "",
  65                         cpu_err_stat & SGIMC_CSTAT_SYSCMD_PAR ? "SYSCMD " : "",
  66                         cpu_err_stat & SGIMC_CSTAT_BAD_DATA ? "BAD_DATA " : "",
  67                         cpu_err_addr);
  68         if (gio_err_stat & GIO_ERRMASK)
  69                 printk(KERN_ERR "GIO error 0x%x:<%s%s%s%s%s%s%s%s> @ 0x%08x\n",
  70                         gio_err_stat,
  71                         gio_err_stat & SGIMC_GSTAT_RD ? "RD " : "",
  72                         gio_err_stat & SGIMC_GSTAT_WR ? "WR " : "",
  73                         gio_err_stat & SGIMC_GSTAT_TIME ? "TIME " : "",
  74                         gio_err_stat & SGIMC_GSTAT_PROM ? "PROM " : "",
  75                         gio_err_stat & SGIMC_GSTAT_ADDR ? "ADDR " : "",
  76                         gio_err_stat & SGIMC_GSTAT_BC ? "BC " : "",
  77                         gio_err_stat & SGIMC_GSTAT_PIO_RD ? "PIO_RD " : "",
  78                         gio_err_stat & SGIMC_GSTAT_PIO_WR ? "PIO_WR " : "",
  79                         gio_err_addr);
  80 }
  81
  82 /*
  83  * MC sends an interrupt whenever bus or parity errors occur. In addition,
  84  * if the error happened during a CPU read, it also asserts the bus error
  85  * pin on the R4K. Code in bus error handler save the MC bus error registers
  86  * and then clear the interrupt when this happens.
  87  */
  88
  89 void ip22_be_interrupt(int irq)
  90 {
  91         const int field = 2 * sizeof(unsigned long);
  92         struct pt_regs *regs = get_irq_regs();
  93
  94         save_and_clear_buserr();
  95         print_buserr();
  96         printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
  97                (regs->cp0_cause & 4) ? "Data" : "Instruction",
  98                field, regs->cp0_epc, field, regs->regs[31]);
  99         /* Assume it would be too dangerous to continue ... */
 100         die_if_kernel("Oops", regs);
 101         force_sig(SIGBUS);
 102 }
 103
 104 static int ip22_be_handler(struct pt_regs *regs, int is_fixup)
 105 {
 106         save_and_clear_buserr();
 107         if (is_fixup)
 108                 return MIPS_BE_FIXUP;
 109         print_buserr();
 110         return MIPS_BE_FATAL;
 111 }
 112
 113 void __init ip22_be_init(void)
 114 {
 115         mips_set_be_handler(ip22_be_handler);
 116 }