1 /*
2  * ip22-berr.c: Bus error handling.
3  *
4  * Copyright (C) 2002, 2003 Ladislav Michl (ladis@linux-mips.org)
5  */
6 
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 
11 #include <asm/addrspace.h>
12 #include <asm/system.h>
13 #include <asm/traps.h>
14 #include <asm/branch.h>
15 #include <asm/sgi/mc.h>
16 #include <asm/sgi/hpc3.h>
17 #include <asm/sgi/ioc.h>
18 #include <asm/sgi/ip22.h>
19 
20 
21 static unsigned int cpu_err_stat;	/* Status reg for CPU */
22 static unsigned int gio_err_stat;	/* Status reg for GIO */
23 static unsigned int cpu_err_addr;	/* Error address reg for CPU */
24 static unsigned int gio_err_addr;	/* Error address reg for GIO */
25 static unsigned int extio_stat;
26 static unsigned int hpc3_berr_stat;	/* Bus error interrupt status */
27 
save_and_clear_buserr(void)28 static void save_and_clear_buserr(void)
29 {
30 	/* save status registers */
31 	cpu_err_addr = sgimc->cerr;
32 	cpu_err_stat = sgimc->cstat;
33 	gio_err_addr = sgimc->gerr;
34 	gio_err_stat = sgimc->gstat;
35 	extio_stat = ip22_is_fullhouse() ? sgioc->extio : (sgint->errstat << 4);
36 	hpc3_berr_stat = hpc3c0->bestat;
37 
38 	sgimc->cstat = sgimc->gstat = 0;
39 }
40 
41 #define GIO_ERRMASK	0xff00
42 #define CPU_ERRMASK	0x3f00
43 
print_buserr(void)44 static void print_buserr(void)
45 {
46 	if (extio_stat & EXTIO_MC_BUSERR)
47 		printk(KERN_ERR "MC Bus Error\n");
48 	if (extio_stat & EXTIO_HPC3_BUSERR)
49 		printk(KERN_ERR "HPC3 Bus Error 0x%x:<id=0x%x,%s,lane=0x%x>\n",
50 			hpc3_berr_stat,
51 			(hpc3_berr_stat & HPC3_BESTAT_PIDMASK) >>
52 					  HPC3_BESTAT_PIDSHIFT,
53 			(hpc3_berr_stat & HPC3_BESTAT_CTYPE) ? "PIO" : "DMA",
54 			hpc3_berr_stat & HPC3_BESTAT_BLMASK);
55 	if (extio_stat & EXTIO_EISA_BUSERR)
56 		printk(KERN_ERR "EISA Bus Error\n");
57 	if (cpu_err_stat & CPU_ERRMASK)
58 		printk(KERN_ERR "CPU error 0x%x<%s%s%s%s%s%s> @ 0x%08x\n",
59 			cpu_err_stat,
60 			cpu_err_stat & SGIMC_CSTAT_RD ? "RD " : "",
61 			cpu_err_stat & SGIMC_CSTAT_PAR ? "PAR " : "",
62 			cpu_err_stat & SGIMC_CSTAT_ADDR ? "ADDR " : "",
63 			cpu_err_stat & SGIMC_CSTAT_SYSAD_PAR ? "SYSAD " : "",
64 			cpu_err_stat & SGIMC_CSTAT_SYSCMD_PAR ? "SYSCMD " : "",
65 			cpu_err_stat & SGIMC_CSTAT_BAD_DATA ? "BAD_DATA " : "",
66 			cpu_err_addr);
67 	if (gio_err_stat & GIO_ERRMASK)
68 		printk(KERN_ERR "GIO error 0x%x:<%s%s%s%s%s%s%s%s> @ 0x08%x\n",
69 			gio_err_stat,
70 			gio_err_stat & SGIMC_GSTAT_RD ? "RD " : "",
71 			gio_err_stat & SGIMC_GSTAT_WR ? "WR " : "",
72 			gio_err_stat & SGIMC_GSTAT_TIME ? "TIME " : "",
73 			gio_err_stat & SGIMC_GSTAT_PROM ? "PROM " : "",
74 			gio_err_stat & SGIMC_GSTAT_ADDR ? "ADDR " : "",
75 			gio_err_stat & SGIMC_GSTAT_BC ? "BC " : "",
76 			gio_err_stat & SGIMC_GSTAT_PIO_RD ? "PIO_RD " : "",
77 			gio_err_stat & SGIMC_GSTAT_PIO_WR ? "PIO_WR " : "",
78 			gio_err_addr);
79 }
80 
81 /*
82  * MC sends an interrupt whenever bus or parity errors occur. In addition,
83  * if the error happened during a CPU read, it also asserts the bus error
84  * pin on the R4K. Code in bus error handler save the MC bus error registers
85  * and then clear the interrupt when this happens.
86  */
87 
ip22_be_interrupt(int irq,struct pt_regs * regs)88 void ip22_be_interrupt(int irq, struct pt_regs *regs)
89 {
90 	const int field = 2 * sizeof(unsigned long);
91 
92 	save_and_clear_buserr();
93 	print_buserr();
94 	printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
95 	       (regs->cp0_cause & 4) ? "Data" : "Instruction",
96 	       field, regs->cp0_epc, field, regs->regs[31]);
97 	/* Assume it would be too dangerous to continue ... */
98 	die_if_kernel("Oops", regs);
99 	force_sig(SIGBUS, current);
100 }
101 
ip22_be_handler(struct pt_regs * regs,int is_fixup)102 static int ip22_be_handler(struct pt_regs *regs, int is_fixup)
103 {
104 	save_and_clear_buserr();
105 	if (is_fixup)
106 		return MIPS_BE_FIXUP;
107 	print_buserr();
108 	return MIPS_BE_FATAL;
109 }
110 
ip22_be_init(void)111 void __init ip22_be_init(void)
112 {
113 	board_be_handler = ip22_be_handler;
114 }
115