From 69c75fb458cd81bb29e1d9580469110b00316748 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Wed, 22 Jun 2005 20:58:45 +0000 Subject: [PATCH] Actual handlers for bus errors for Pmax and 3min. Signed-off-by: Ralf Baechle diff --git a/arch/mips/dec/kn01-berr.c b/arch/mips/dec/kn01-berr.c new file mode 100644 --- arch/mips/dec/kn01-berr.c | 200 ++++++++++++++++++++++++++++++++++++ arch/mips/dec/kn02xa-berr.c | 138 +++++++++++++++++++++++++ 2 files changed, 338 insertions(+) create mode 100644 arch/mips/dec/kn01-berr.c create mode 100644 arch/mips/dec/kn02xa-berr.c diff --git a/arch/mips/dec/kn01-berr.c b/arch/mips/dec/kn01-berr.c new file mode 100644 index 00000000000..8ec7b30a90c --- /dev/null +++ b/arch/mips/dec/kn01-berr.c @@ -0,0 +1,200 @@ +/* + * linux/arch/mips/dec/kn01-berr.c + * + * Bus error event handling code for DECstation/DECsystem 3100 + * and 2100 (KN01) systems equipped with parity error detection + * logic. + * + * Copyright (c) 2005 Maciej W. Rozycki + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include + + +/* CP0 hazard avoidance. */ +#define BARRIER \ + __asm__ __volatile__( \ + ".set push\n\t" \ + ".set noreorder\n\t" \ + "nop\n\t" \ + ".set pop\n\t") + +/* + * Bits 7:0 of the Control Register are write-only -- the + * corresponding bits of the Status Register have a different + * meaning. Hence we use a cache. It speeds up things a bit + * as well. + * + * There is no default value -- it has to be initialized. + */ +u16 cached_kn01_csr; +DEFINE_SPINLOCK(kn01_lock); + + +static inline void dec_kn01_be_ack(void) +{ + volatile u16 *csr = (void *)(KN01_SLOT_BASE + KN01_CSR); + unsigned long flags; + + spin_lock_irqsave(&kn01_lock, flags); + + *csr = cached_kn01_csr | KN01_CSR_MEMERR; /* Clear bus IRQ. */ + iob(); + + spin_unlock_irqrestore(&kn01_lock, flags); +} + +static int dec_kn01_be_backend(struct pt_regs *regs, int is_fixup, int invoker) +{ + volatile u32 *kn01_erraddr = (void *)(KN01_SLOT_BASE + KN01_ERRADDR); + + static const char excstr[] = "exception"; + static const char intstr[] = "interrupt"; + static const char cpustr[] = "CPU"; + static const char mreadstr[] = "memory read"; + static const char readstr[] = "read"; + static const char writestr[] = "write"; + static const char timestr[] = "timeout"; + static const char paritystr[] = "parity error"; + + int data = regs->cp0_cause & 4; + unsigned int __user *pc = (unsigned int __user *)regs->cp0_epc + + ((regs->cp0_cause & CAUSEF_BD) != 0); + union mips_instruction insn; + unsigned long entrylo, offset; + long asid, entryhi, vaddr; + + const char *kind, *agent, *cycle, *event; + unsigned long address; + + u32 erraddr = *kn01_erraddr; + int action = MIPS_BE_FATAL; + + /* Ack ASAP, so that any subsequent errors get caught. */ + dec_kn01_be_ack(); + + kind = invoker ? intstr : excstr; + + agent = cpustr; + + if (invoker) + address = erraddr; + else { + /* Bloody hardware doesn't record the address for reads... */ + if (data) { + /* This never faults. */ + __get_user(insn.word, pc); + vaddr = regs->regs[insn.i_format.rs] + + insn.i_format.simmediate; + } else + vaddr = (long)pc; + if (KSEGX(vaddr) == CKSEG0 || KSEGX(vaddr) == CKSEG1) + address = CPHYSADDR(vaddr); + else { + /* Peek at what physical address the CPU used. */ + asid = read_c0_entryhi(); + entryhi = asid & (PAGE_SIZE - 1); + entryhi |= vaddr & ~(PAGE_SIZE - 1); + write_c0_entryhi(entryhi); + BARRIER; + tlb_probe(); + /* No need to check for presence. */ + tlb_read(); + entrylo = read_c0_entrylo0(); + write_c0_entryhi(asid); + offset = vaddr & (PAGE_SIZE - 1); + address = (entrylo & ~(PAGE_SIZE - 1)) | offset; + } + } + + /* Treat low 256MB as memory, high -- as I/O. */ + if (address < 0x10000000) { + cycle = mreadstr; + event = paritystr; + } else { + cycle = invoker ? writestr : readstr; + event = timestr; + } + + if (is_fixup) + action = MIPS_BE_FIXUP; + + if (action != MIPS_BE_FIXUP) + printk(KERN_ALERT "Bus error %s: %s %s %s at %#010lx\n", + kind, agent, cycle, event, address); + + return action; +} + +int dec_kn01_be_handler(struct pt_regs *regs, int is_fixup) +{ + return dec_kn01_be_backend(regs, is_fixup, 0); +} + +irqreturn_t dec_kn01_be_interrupt(int irq, void *dev_id, + struct pt_regs *regs) +{ + volatile u16 *csr = (void *)(KN01_SLOT_BASE + KN01_CSR); + int action; + + if (!(*csr & KN01_CSR_MEMERR)) + return IRQ_NONE; /* Must have been video. */ + + action = dec_kn01_be_backend(regs, 0, 1); + + if (action == MIPS_BE_DISCARD) + return IRQ_HANDLED; + + /* + * FIXME: Find the affected processes and kill them, otherwise + * we must die. + * + * The interrupt is asynchronously delivered thus EPC and RA + * may be irrelevant, but are printed for a reference. + */ + printk(KERN_ALERT "Fatal bus interrupt, epc == %08lx, ra == %08lx\n", + regs->cp0_epc, regs->regs[31]); + die("Unrecoverable bus error", regs); +} + + +void __init dec_kn01_be_init(void) +{ + volatile u16 *csr = (void *)(KN01_SLOT_BASE + KN01_CSR); + unsigned long flags; + + spin_lock_irqsave(&kn01_lock, flags); + + /* Preset write-only bits of the Control Register cache. */ + cached_kn01_csr = *csr; + cached_kn01_csr &= KN01_CSR_STATUS | KN01_CSR_PARDIS | KN01_CSR_TXDIS; + cached_kn01_csr |= KN01_CSR_LEDS; + + /* Enable parity error detection. */ + cached_kn01_csr &= ~KN01_CSR_PARDIS; + *csr = cached_kn01_csr; + iob(); + + spin_unlock_irqrestore(&kn01_lock, flags); + + /* Clear any leftover errors from the firmware. */ + dec_kn01_be_ack(); +} diff --git a/arch/mips/dec/kn02xa-berr.c b/arch/mips/dec/kn02xa-berr.c new file mode 100644 index 00000000000..c2990956662 --- /dev/null +++ b/arch/mips/dec/kn02xa-berr.c @@ -0,0 +1,138 @@ +/* + * linux/arch/mips/dec/kn02xa-berr.c + * + * Bus error event handling code for 5000-series systems equipped + * with parity error detection logic, i.e. DECstation/DECsystem + * 5000/120, /125, /133 (KN02-BA), 5000/150 (KN04-BA) and Personal + * DECstation/DECsystem 5000/20, /25, /33 (KN02-CA), 5000/50 + * (KN04-CA) systems. + * + * Copyright (c) 2005 Maciej W. Rozycki + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include + +#include +#include + +#include +#include +#include + +static inline void dec_kn02xa_be_ack(void) +{ + volatile u32 *mer = (void *)KN02XA_MER; + volatile u32 *mem_intr = (void *)KN02XA_MEM_INTR; + + *mer = KN02CA_MER_INTR; /* Clear errors; keep the ARC IRQ. */ + *mem_intr = 0; /* Any write clears the bus IRQ. */ + iob(); +} + +static int dec_kn02xa_be_backend(struct pt_regs *regs, int is_fixup, + int invoker) +{ + volatile u32 *kn02xa_mer = (void *)KN02XA_MER; + volatile u32 *kn02xa_ear = (void *)KN02XA_EAR; + + static const char excstr[] = "exception"; + static const char intstr[] = "interrupt"; + static const char cpustr[] = "CPU"; + static const char mreadstr[] = "memory read"; + static const char readstr[] = "read"; + static const char writestr[] = "write"; + static const char timestr[] = "timeout"; + static const char paritystr[] = "parity error"; + static const char lanestat[][4] = { " OK", "BAD" }; + + const char *kind, *agent, *cycle, *event; + unsigned long address; + + u32 mer = *kn02xa_mer; + u32 ear = *kn02xa_ear; + int action = MIPS_BE_FATAL; + + /* Ack ASAP, so that any subsequent errors get caught. */ + dec_kn02xa_be_ack(); + + kind = invoker ? intstr : excstr; + + /* No DMA errors? */ + agent = cpustr; + + address = ear & KN02XA_EAR_ADDRESS; + + /* Low 256MB is decoded as memory, high -- as TC. */ + if (address < 0x10000000) { + cycle = mreadstr; + event = paritystr; + } else { + cycle = invoker ? writestr : readstr; + event = timestr; + } + + if (is_fixup) + action = MIPS_BE_FIXUP; + + if (action != MIPS_BE_FIXUP) + printk(KERN_ALERT "Bus error %s: %s %s %s at %#010lx\n", + kind, agent, cycle, event, address); + + if (action != MIPS_BE_FIXUP && address < 0x10000000) + printk(KERN_ALERT " Byte lane status %#3x -- " + "#3: %s, #2: %s, #1: %s, #0: %s\n", + (mer & KN02XA_MER_BYTERR) >> 8, + lanestat[(mer & KN02XA_MER_BYTERR_3) != 0], + lanestat[(mer & KN02XA_MER_BYTERR_2) != 0], + lanestat[(mer & KN02XA_MER_BYTERR_1) != 0], + lanestat[(mer & KN02XA_MER_BYTERR_0) != 0]); + + return action; +} + +int dec_kn02xa_be_handler(struct pt_regs *regs, int is_fixup) +{ + return dec_kn02xa_be_backend(regs, is_fixup, 0); +} + +irqreturn_t dec_kn02xa_be_interrupt(int irq, void *dev_id, + struct pt_regs *regs) +{ + int action = dec_kn02xa_be_backend(regs, 0, 1); + + if (action == MIPS_BE_DISCARD) + return IRQ_HANDLED; + + /* + * FIXME: Find the affected processes and kill them, otherwise + * we must die. + * + * The interrupt is asynchronously delivered thus EPC and RA + * may be irrelevant, but are printed for a reference. + */ + printk(KERN_ALERT "Fatal bus interrupt, epc == %08lx, ra == %08lx\n", + regs->cp0_epc, regs->regs[31]); + die("Unrecoverable bus error", regs); +} + + +void __init dec_kn02xa_be_init(void) +{ + volatile u32 *mbcs = (void *)(KN4K_SLOT_BASE + KN4K_MB_CSR); + + /* For KN04 we need to make sure EE (?) is enabled in the MB. */ + if (current_cpu_data.cputype == CPU_R4000SC) + *mbcs |= KN4K_MB_CSR_EE; + fast_iob(); + + /* Clear any leftover errors from the firmware. */ + dec_kn02xa_be_ack(); +} -- 2.20.1