diff options
Diffstat (limited to 'arch/mips/sgi-ip22/ip28-berr.c')
| -rw-r--r-- | arch/mips/sgi-ip22/ip28-berr.c | 502 |
1 files changed, 502 insertions, 0 deletions
diff --git a/arch/mips/sgi-ip22/ip28-berr.c b/arch/mips/sgi-ip22/ip28-berr.c new file mode 100644 index 000000000000..30e12e2ec4b5 --- /dev/null +++ b/arch/mips/sgi-ip22/ip28-berr.c @@ -0,0 +1,502 @@ +/* + * ip28-berr.c: Bus error handling. + * + * Copyright (C) 2002, 2003 Ladislav Michl (ladis@linux-mips.org) + * Copyright (C) 2005 Peter Fuerst (pf@net.alphadv.de) - IP28 + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/seq_file.h> + +#include <asm/addrspace.h> +#include <asm/system.h> +#include <asm/traps.h> +#include <asm/branch.h> +#include <asm/irq_regs.h> +#include <asm/sgi/mc.h> +#include <asm/sgi/hpc3.h> +#include <asm/sgi/ioc.h> +#include <asm/sgi/ip22.h> +#include <asm/r4kcache.h> +#include <asm/uaccess.h> +#include <asm/bootinfo.h> + +static unsigned int count_be_is_fixup; +static unsigned int count_be_handler; +static unsigned int count_be_interrupt; +static int debug_be_interrupt; + +static unsigned int cpu_err_stat; /* Status reg for CPU */ +static unsigned int gio_err_stat; /* Status reg for GIO */ +static unsigned int cpu_err_addr; /* Error address reg for CPU */ +static unsigned int gio_err_addr; /* Error address reg for GIO */ +static unsigned int extio_stat; +static unsigned int hpc3_berr_stat; /* Bus error interrupt status */ + +struct hpc3_stat { + unsigned long addr; + unsigned int ctrl; + unsigned int cbp; + unsigned int ndptr; +}; + +static struct { + struct hpc3_stat pbdma[8]; + struct hpc3_stat scsi[2]; + struct hpc3_stat ethrx, ethtx; +} hpc3; + +static struct { + unsigned long err_addr; + struct { + u32 lo; + u32 hi; + } tags[1][2], tagd[4][2], tagi[4][2]; /* Way 0/1 */ +} cache_tags; + +static inline void save_cache_tags(unsigned busaddr) +{ + unsigned long addr = CAC_BASE | busaddr; + int i; + cache_tags.err_addr = addr; + + /* + * Starting with a bus-address, save secondary cache (indexed by + * PA[23..18:7..6]) tags first. + */ + addr &= ~1L; +#define tag cache_tags.tags[0] + cache_op(Index_Load_Tag_S, addr); + tag[0].lo = read_c0_taglo(); /* PA[35:18], VA[13:12] */ + tag[0].hi = read_c0_taghi(); /* PA[39:36] */ + cache_op(Index_Load_Tag_S, addr | 1L); + tag[1].lo = read_c0_taglo(); /* PA[35:18], VA[13:12] */ + tag[1].hi = read_c0_taghi(); /* PA[39:36] */ +#undef tag + + /* + * Save all primary data cache (indexed by VA[13:5]) tags which + * might fit to this bus-address, knowing that VA[11:0] == PA[11:0]. + * Saving all tags and evaluating them later is easier and safer + * than relying on VA[13:12] from the secondary cache tags to pick + * matching primary tags here already. + */ + addr &= (0xffL << 56) | ((1 << 12) - 1); +#define tag cache_tags.tagd[i] + for (i = 0; i < 4; ++i, addr += (1 << 12)) { + cache_op(Index_Load_Tag_D, addr); + tag[0].lo = read_c0_taglo(); /* PA[35:12] */ + tag[0].hi = read_c0_taghi(); /* PA[39:36] */ + cache_op(Index_Load_Tag_D, addr | 1L); + tag[1].lo = read_c0_taglo(); /* PA[35:12] */ + tag[1].hi = read_c0_taghi(); /* PA[39:36] */ + } +#undef tag + + /* + * Save primary instruction cache (indexed by VA[13:6]) tags + * the same way. + */ + addr &= (0xffL << 56) | ((1 << 12) - 1); +#define tag cache_tags.tagi[i] + for (i = 0; i < 4; ++i, addr += (1 << 12)) { + cache_op(Index_Load_Tag_I, addr); + tag[0].lo = read_c0_taglo(); /* PA[35:12] */ + tag[0].hi = read_c0_taghi(); /* PA[39:36] */ + cache_op(Index_Load_Tag_I, addr | 1L); + tag[1].lo = read_c0_taglo(); /* PA[35:12] */ + tag[1].hi = read_c0_taghi(); /* PA[39:36] */ + } +#undef tag +} + +#define GIO_ERRMASK 0xff00 +#define CPU_ERRMASK 0x3f00 + +static void save_and_clear_buserr(void) +{ + int i; + + /* save status registers */ + cpu_err_addr = sgimc->cerr; + cpu_err_stat = sgimc->cstat; + gio_err_addr = sgimc->gerr; + gio_err_stat = sgimc->gstat; + extio_stat = sgioc->extio; + hpc3_berr_stat = hpc3c0->bestat; + + hpc3.scsi[0].addr = (unsigned long)&hpc3c0->scsi_chan0; + hpc3.scsi[0].ctrl = hpc3c0->scsi_chan0.ctrl; /* HPC3_SCTRL_ACTIVE ? */ + hpc3.scsi[0].cbp = hpc3c0->scsi_chan0.cbptr; + hpc3.scsi[0].ndptr = hpc3c0->scsi_chan0.ndptr; + + hpc3.scsi[1].addr = (unsigned long)&hpc3c0->scsi_chan1; + hpc3.scsi[1].ctrl = hpc3c0->scsi_chan1.ctrl; /* HPC3_SCTRL_ACTIVE ? */ + hpc3.scsi[1].cbp = hpc3c0->scsi_chan1.cbptr; + hpc3.scsi[1].ndptr = hpc3c0->scsi_chan1.ndptr; + + hpc3.ethrx.addr = (unsigned long)&hpc3c0->ethregs.rx_cbptr; + hpc3.ethrx.ctrl = hpc3c0->ethregs.rx_ctrl; /* HPC3_ERXCTRL_ACTIVE ? */ + hpc3.ethrx.cbp = hpc3c0->ethregs.rx_cbptr; + hpc3.ethrx.ndptr = hpc3c0->ethregs.rx_ndptr; + + hpc3.ethtx.addr = (unsigned long)&hpc3c0->ethregs.tx_cbptr; + hpc3.ethtx.ctrl = hpc3c0->ethregs.tx_ctrl; /* HPC3_ETXCTRL_ACTIVE ? */ + hpc3.ethtx.cbp = hpc3c0->ethregs.tx_cbptr; + hpc3.ethtx.ndptr = hpc3c0->ethregs.tx_ndptr; + + for (i = 0; i < 8; ++i) { + /* HPC3_PDMACTRL_ISACT ? */ + hpc3.pbdma[i].addr = (unsigned long)&hpc3c0->pbdma[i]; + hpc3.pbdma[i].ctrl = hpc3c0->pbdma[i].pbdma_ctrl; + hpc3.pbdma[i].cbp = hpc3c0->pbdma[i].pbdma_bptr; + hpc3.pbdma[i].ndptr = hpc3c0->pbdma[i].pbdma_dptr; + } + i = 0; + if (gio_err_stat & CPU_ERRMASK) + i = gio_err_addr; + if (cpu_err_stat & CPU_ERRMASK) + i = cpu_err_addr; + save_cache_tags(i); + + sgimc->cstat = sgimc->gstat = 0; +} + +static void print_cache_tags(void) +{ + u32 scb, scw; + int i; + + printk(KERN_ERR "Cache tags @ %08x:\n", (unsigned)cache_tags.err_addr); + + /* PA[31:12] shifted to PTag0 (PA[35:12]) format */ + scw = (cache_tags.err_addr >> 4) & 0x0fffff00; + + scb = cache_tags.err_addr & ((1 << 12) - 1) & ~((1 << 5) - 1); + for (i = 0; i < 4; ++i) { /* for each possible VA[13:12] value */ + if ((cache_tags.tagd[i][0].lo & 0x0fffff00) != scw && + (cache_tags.tagd[i][1].lo & 0x0fffff00) != scw) + continue; + printk(KERN_ERR + "D: 0: %08x %08x, 1: %08x %08x (VA[13:5] %04x)\n", + cache_tags.tagd[i][0].hi, cache_tags.tagd[i][0].lo, + cache_tags.tagd[i][1].hi, cache_tags.tagd[i][1].lo, + scb | (1 << 12)*i); + } + scb = cache_tags.err_addr & ((1 << 12) - 1) & ~((1 << 6) - 1); + for (i = 0; i < 4; ++i) { /* for each possible VA[13:12] value */ + if ((cache_tags.tagi[i][0].lo & 0x0fffff00) != scw && + (cache_tags.tagi[i][1].lo & 0x0fffff00) != scw) + continue; + printk(KERN_ERR + "I: 0: %08x %08x, 1: %08x %08x (VA[13:6] %04x)\n", + cache_tags.tagi[i][0].hi, cache_tags.tagi[i][0].lo, + cache_tags.tagi[i][1].hi, cache_tags.tagi[i][1].lo, + scb | (1 << 12)*i); + } + i = read_c0_config(); + scb = i & (1 << 13) ? 7:6; /* scblksize = 2^[7..6] */ + scw = ((i >> 16) & 7) + 19 - 1; /* scwaysize = 2^[24..19] / 2 */ + + i = ((1 << scw) - 1) & ~((1 << scb) - 1); + printk(KERN_ERR "S: 0: %08x %08x, 1: %08x %08x (PA[%u:%u] %05x)\n", + cache_tags.tags[0][0].hi, cache_tags.tags[0][0].lo, + cache_tags.tags[0][1].hi, cache_tags.tags[0][1].lo, + scw-1, scb, i & (unsigned)cache_tags.err_addr); +} + +static inline const char *cause_excode_text(int cause) +{ + static const char *txt[32] = + { "Interrupt", + "TLB modification", + "TLB (load or instruction fetch)", + "TLB (store)", + "Address error (load or instruction fetch)", + "Address error (store)", + "Bus error (instruction fetch)", + "Bus error (data: load or store)", + "Syscall", + "Breakpoint", + "Reserved instruction", + "Coprocessor unusable", + "Arithmetic Overflow", + "Trap", + "14", + "Floating-Point", + "16", "17", "18", "19", "20", "21", "22", + "Watch Hi/Lo", + "24", "25", "26", "27", "28", "29", "30", "31", + }; + return txt[(cause & 0x7c) >> 2]; +} + +static void print_buserr(const struct pt_regs *regs) +{ + const int field = 2 * sizeof(unsigned long); + int error = 0; + + if (extio_stat & EXTIO_MC_BUSERR) { + printk(KERN_ERR "MC Bus Error\n"); + error |= 1; + } + if (extio_stat & EXTIO_HPC3_BUSERR) { + printk(KERN_ERR "HPC3 Bus Error 0x%x:<id=0x%x,%s,lane=0x%x>\n", + hpc3_berr_stat, + (hpc3_berr_stat & HPC3_BESTAT_PIDMASK) >> + HPC3_BESTAT_PIDSHIFT, + (hpc3_berr_stat & HPC3_BESTAT_CTYPE) ? "PIO" : "DMA", + hpc3_berr_stat & HPC3_BESTAT_BLMASK); + error |= 2; + } + if (extio_stat & EXTIO_EISA_BUSERR) { + printk(KERN_ERR "EISA Bus Error\n"); + error |= 4; + } + if (cpu_err_stat & CPU_ERRMASK) { + printk(KERN_ERR "CPU error 0x%x<%s%s%s%s%s%s> @ 0x%08x\n", + cpu_err_stat, + cpu_err_stat & SGIMC_CSTAT_RD ? "RD " : "", + cpu_err_stat & SGIMC_CSTAT_PAR ? "PAR " : "", + cpu_err_stat & SGIMC_CSTAT_ADDR ? "ADDR " : "", + cpu_err_stat & SGIMC_CSTAT_SYSAD_PAR ? "SYSAD " : "", + cpu_err_stat & SGIMC_CSTAT_SYSCMD_PAR ? "SYSCMD " : "", + cpu_err_stat & SGIMC_CSTAT_BAD_DATA ? "BAD_DATA " : "", + cpu_err_addr); + error |= 8; + } + if (gio_err_stat & GIO_ERRMASK) { + printk(KERN_ERR "GIO error 0x%x:<%s%s%s%s%s%s%s%s> @ 0x%08x\n", + gio_err_stat, + gio_err_stat & SGIMC_GSTAT_RD ? "RD " : "", + gio_err_stat & SGIMC_GSTAT_WR ? "WR " : "", + gio_err_stat & SGIMC_GSTAT_TIME ? "TIME " : "", + gio_err_stat & SGIMC_GSTAT_PROM ? "PROM " : "", + gio_err_stat & SGIMC_GSTAT_ADDR ? "ADDR " : "", + gio_err_stat & SGIMC_GSTAT_BC ? "BC " : "", + gio_err_stat & SGIMC_GSTAT_PIO_RD ? "PIO_RD " : "", + gio_err_stat & SGIMC_GSTAT_PIO_WR ? "PIO_WR " : "", + gio_err_addr); + error |= 16; + } + if (!error) + printk(KERN_ERR "MC: Hmm, didn't find any error condition.\n"); + else { + printk(KERN_ERR "CP0: config %08x, " + "MC: cpuctrl0/1: %08x/%05x, giopar: %04x\n" + "MC: cpu/gio_memacc: %08x/%05x, memcfg0/1: %08x/%08x\n", + read_c0_config(), + sgimc->cpuctrl0, sgimc->cpuctrl0, sgimc->giopar, + sgimc->cmacc, sgimc->gmacc, + sgimc->mconfig0, sgimc->mconfig1); + print_cache_tags(); + } + printk(KERN_ALERT "%s, epc == %0*lx, ra == %0*lx\n", + cause_excode_text(regs->cp0_cause), + field, regs->cp0_epc, field, regs->regs[31]); +} + +/* + * Check, whether MC's (virtual) DMA address caused the bus error. + * See "Virtual DMA Specification", Draft 1.5, Feb 13 1992, SGI + */ + +static int addr_is_ram(unsigned long addr, unsigned sz) +{ + int i; + + for (i = 0; i < boot_mem_map.nr_map; i++) { + unsigned long a = boot_mem_map.map[i].addr; + if (a <= addr && addr+sz <= a+boot_mem_map.map[i].size) + return 1; + } + return 0; +} + +static int check_microtlb(u32 hi, u32 lo, unsigned long vaddr) +{ + /* This is likely rather similar to correct code ;-) */ + + vaddr &= 0x7fffffff; /* Doc. states that top bit is ignored */ + + /* If tlb-entry is valid and VPN-high (bits [30:21] ?) matches... */ + if ((lo & 2) && (vaddr >> 21) == ((hi<<1) >> 22)) { + u32 ctl = sgimc->dma_ctrl; + if (ctl & 1) { + unsigned int pgsz = (ctl & 2) ? 14:12; /* 16k:4k */ + /* PTEIndex is VPN-low (bits [22:14]/[20:12] ?) */ + unsigned long pte = (lo >> 6) << 12; /* PTEBase */ + pte += 8*((vaddr >> pgsz) & 0x1ff); + if (addr_is_ram(pte, 8)) { + /* + * Note: Since DMA hardware does look up + * translation on its own, this PTE *must* + * match the TLB/EntryLo-register format ! + */ + unsigned long a = *(unsigned long *) + PHYS_TO_XKSEG_UNCACHED(pte); + a = (a & 0x3f) << 6; /* PFN */ + a += vaddr & ((1 << pgsz) - 1); + return (cpu_err_addr == a); + } + } + } + return 0; +} + +static int check_vdma_memaddr(void) +{ + if (cpu_err_stat & CPU_ERRMASK) { + u32 a = sgimc->maddronly; + + if (!(sgimc->dma_ctrl & 0x100)) /* Xlate-bit clear ? */ + return (cpu_err_addr == a); + + if (check_microtlb(sgimc->dtlb_hi0, sgimc->dtlb_lo0, a) || + check_microtlb(sgimc->dtlb_hi1, sgimc->dtlb_lo1, a) || + check_microtlb(sgimc->dtlb_hi2, sgimc->dtlb_lo2, a) || + check_microtlb(sgimc->dtlb_hi3, sgimc->dtlb_lo3, a)) + return 1; + } + return 0; +} + +static int check_vdma_gioaddr(void) +{ + if (gio_err_stat & GIO_ERRMASK) { + u32 a = sgimc->gio_dma_trans; + a = (sgimc->gmaddronly & ~a) | (sgimc->gio_dma_sbits & a); + return (gio_err_addr == a); + } + return 0; +} + +/* + * MC sends an interrupt whenever bus or parity errors occur. In addition, + * if the error happened during a CPU read, it also asserts the bus error + * pin on the R4K. Code in bus error handler save the MC bus error registers + * and then clear the interrupt when this happens. + */ + +static int ip28_be_interrupt(const struct pt_regs *regs) +{ + int i; + + save_and_clear_buserr(); + /* + * Try to find out, whether we got here by a mispredicted speculative + * load/store operation. If so, it's not fatal, we can go on. + */ + /* Any cause other than "Interrupt" (ExcCode 0) is fatal. */ + if (regs->cp0_cause & CAUSEF_EXCCODE) + goto mips_be_fatal; + + /* Any cause other than "Bus error interrupt" (IP6) is weird. */ + if ((regs->cp0_cause & CAUSEF_IP6) != CAUSEF_IP6) + goto mips_be_fatal; + + if (extio_stat & (EXTIO_HPC3_BUSERR | EXTIO_EISA_BUSERR)) + goto mips_be_fatal; + + /* Any state other than "Memory bus error" is fatal. */ + if (cpu_err_stat & CPU_ERRMASK & ~SGIMC_CSTAT_ADDR) + goto mips_be_fatal; + + /* GIO errors other than timeouts are fatal */ + if (gio_err_stat & GIO_ERRMASK & ~SGIMC_GSTAT_TIME) + goto mips_be_fatal; + + /* + * Now we have an asynchronous bus error, speculatively or DMA caused. + * Need to search all DMA descriptors for the error address. + */ + for (i = 0; i < sizeof(hpc3)/sizeof(struct hpc3_stat); ++i) { + struct hpc3_stat *hp = (struct hpc3_stat *)&hpc3 + i; + if ((cpu_err_stat & CPU_ERRMASK) && + (cpu_err_addr == hp->ndptr || cpu_err_addr == hp->cbp)) + break; + if ((gio_err_stat & GIO_ERRMASK) && + (gio_err_addr == hp->ndptr || gio_err_addr == hp->cbp)) + break; + } + if (i < sizeof(hpc3)/sizeof(struct hpc3_stat)) { + struct hpc3_stat *hp = (struct hpc3_stat *)&hpc3 + i; + printk(KERN_ERR "at DMA addresses: HPC3 @ %08lx:" + " ctl %08x, ndp %08x, cbp %08x\n", + CPHYSADDR(hp->addr), hp->ctrl, hp->ndptr, hp->cbp); + goto mips_be_fatal; + } + /* Check MC's virtual DMA stuff. */ + if (check_vdma_memaddr()) { + printk(KERN_ERR "at GIO DMA: mem address 0x%08x.\n", + sgimc->maddronly); + goto mips_be_fatal; + } + if (check_vdma_gioaddr()) { + printk(KERN_ERR "at GIO DMA: gio address 0x%08x.\n", + sgimc->gmaddronly); + goto mips_be_fatal; + } + /* A speculative bus error... */ + if (debug_be_interrupt) { + print_buserr(regs); + printk(KERN_ERR "discarded!\n"); + } + return MIPS_BE_DISCARD; + +mips_be_fatal: + print_buserr(regs); + return MIPS_BE_FATAL; +} + +void ip22_be_interrupt(int irq) +{ + const struct pt_regs *regs = get_irq_regs(); + + count_be_interrupt++; + + if (ip28_be_interrupt(regs) != MIPS_BE_DISCARD) { + /* Assume it would be too dangerous to continue ... */ + die_if_kernel("Oops", regs); + force_sig(SIGBUS, current); + } else if (debug_be_interrupt) + show_regs((struct pt_regs *)regs); +} + +static int ip28_be_handler(struct pt_regs *regs, int is_fixup) +{ + /* + * We arrive here only in the unusual case of do_be() invocation, + * i.e. by a bus error exception without a bus error interrupt. + */ + if (is_fixup) { + count_be_is_fixup++; + save_and_clear_buserr(); + return MIPS_BE_FIXUP; + } + count_be_handler++; + return ip28_be_interrupt(regs); +} + +void __init ip22_be_init(void) +{ + board_be_handler = ip28_be_handler; +} + +int ip28_show_be_info(struct seq_file *m) +{ + seq_printf(m, "IP28 be fixups\t\t: %u\n", count_be_is_fixup); + seq_printf(m, "IP28 be interrupts\t: %u\n", count_be_interrupt); + seq_printf(m, "IP28 be handler\t\t: %u\n", count_be_handler); + + return 0; +} + +static int __init debug_be_setup(char *str) +{ + debug_be_interrupt++; + return 1; +} +__setup("ip28_debug_be", debug_be_setup); |