// SPDX-License-Identifier: GPL-2.0
/*
 *      linux/arch/alpha/kernel/err_ev6.c
 *
 *      Copyright (C) 2000 Jeff Wiedemeier (Compaq Computer Corporation)
 *
 *      Error handling code supporting Alpha systems
 */

#include <linux/sched.h>

#include <asm/io.h>
#include <asm/irq_regs.h>
#include <asm/hwrpb.h>
#include <asm/smp.h>
#include <asm/err_common.h>
#include <asm/err_ev6.h>

#include "err_impl.h"
#include "proto.h"

static int
ev6_parse_ibox(u64 i_stat, int print)
{
        int status = MCHK_DISPOSITION_REPORT;

#define EV6__I_STAT__PAR        (1UL << 29)
#define EV6__I_STAT__ERRMASK    (EV6__I_STAT__PAR)

        if (!(i_stat & EV6__I_STAT__ERRMASK))
                return MCHK_DISPOSITION_UNKNOWN_ERROR;

        if (!print)
                return status;

        if (i_stat & EV6__I_STAT__PAR)
                printk("%s    Icache parity error\n", err_print_prefix);

        return status;
}

static int
ev6_parse_mbox(u64 mm_stat, u64 d_stat, u64 c_stat, int print)
{
        int status = MCHK_DISPOSITION_REPORT;

#define EV6__MM_STAT__DC_TAG_PERR       (1UL << 10)
#define EV6__MM_STAT__ERRMASK           (EV6__MM_STAT__DC_TAG_PERR)
#define EV6__D_STAT__TPERR_P0           (1UL << 0)
#define EV6__D_STAT__TPERR_P1           (1UL << 1)
#define EV6__D_STAT__ECC_ERR_ST         (1UL << 2)
#define EV6__D_STAT__ECC_ERR_LD         (1UL << 3)
#define EV6__D_STAT__SEO                (1UL << 4)
#define EV6__D_STAT__ERRMASK            (EV6__D_STAT__TPERR_P0 |        \
                                         EV6__D_STAT__TPERR_P1 |        \
                                         EV6__D_STAT__ECC_ERR_ST |      \
                                         EV6__D_STAT__ECC_ERR_LD |      \
                                         EV6__D_STAT__SEO)

        if (!(d_stat & EV6__D_STAT__ERRMASK) && 
            !(mm_stat & EV6__MM_STAT__ERRMASK))
                return MCHK_DISPOSITION_UNKNOWN_ERROR;

        if (!print)
                return status;

        if (mm_stat & EV6__MM_STAT__DC_TAG_PERR)
                printk("%s    Dcache tag parity error on probe\n",
                       err_print_prefix);
        if (d_stat & EV6__D_STAT__TPERR_P0)
                printk("%s    Dcache tag parity error - pipe 0\n",
                       err_print_prefix);
        if (d_stat & EV6__D_STAT__TPERR_P1)
                printk("%s    Dcache tag parity error - pipe 1\n",
                       err_print_prefix);
        if (d_stat & EV6__D_STAT__ECC_ERR_ST)
                printk("%s    ECC error occurred on a store\n", 
                       err_print_prefix);
        if (d_stat & EV6__D_STAT__ECC_ERR_LD)
                printk("%s    ECC error occurred on a %s load\n",
                       err_print_prefix,
                       c_stat ? "" : "speculative ");
        if (d_stat & EV6__D_STAT__SEO)
                printk("%s    Dcache second error\n", err_print_prefix);

        return status;
}

static int
ev6_parse_cbox(u64 c_addr, u64 c1_syn, u64 c2_syn, 
               u64 c_stat, u64 c_sts, int print)
{
        static const char * const sourcename[] = {
                "UNKNOWN", "UNKNOWN", "UNKNOWN",
                "MEMORY", "BCACHE", "DCACHE",
                "BCACHE PROBE", "BCACHE PROBE"
        };
        static const char * const streamname[] = { "D", "I" };
        static const char * const bitsname[] = { "SINGLE", "DOUBLE" };
        int status = MCHK_DISPOSITION_REPORT;
        int source = -1, stream = -1, bits = -1;

#define EV6__C_STAT__BC_PERR            (0x01)
#define EV6__C_STAT__DC_PERR            (0x02)
#define EV6__C_STAT__DSTREAM_MEM_ERR    (0x03)
#define EV6__C_STAT__DSTREAM_BC_ERR     (0x04)
#define EV6__C_STAT__DSTREAM_DC_ERR     (0x05)
#define EV6__C_STAT__PROBE_BC_ERR0      (0x06)  /* both 6 and 7 indicate... */
#define EV6__C_STAT__PROBE_BC_ERR1      (0x07)  /* ...probe bc error.       */
#define EV6__C_STAT__ISTREAM_MEM_ERR    (0x0B)
#define EV6__C_STAT__ISTREAM_BC_ERR     (0x0C)
#define EV6__C_STAT__DSTREAM_MEM_DBL    (0x13)
#define EV6__C_STAT__DSTREAM_BC_DBL     (0x14)
#define EV6__C_STAT__ISTREAM_MEM_DBL    (0x1B)
#define EV6__C_STAT__ISTREAM_BC_DBL     (0x1C)
#define EV6__C_STAT__SOURCE_MEMORY      (0x03)
#define EV6__C_STAT__SOURCE_BCACHE      (0x04)
#define EV6__C_STAT__SOURCE__S          (0)
#define EV6__C_STAT__SOURCE__M          (0x07)
#define EV6__C_STAT__ISTREAM__S         (3)
#define EV6__C_STAT__ISTREAM__M         (0x01)
#define EV6__C_STAT__DOUBLE__S          (4)
#define EV6__C_STAT__DOUBLE__M          (0x01)
#define EV6__C_STAT__ERRMASK            (0x1F)
#define EV6__C_STS__SHARED              (1 << 0)
#define EV6__C_STS__DIRTY               (1 << 1)
#define EV6__C_STS__VALID               (1 << 2)
#define EV6__C_STS__PARITY              (1 << 3)

        if (!(c_stat & EV6__C_STAT__ERRMASK))
                return MCHK_DISPOSITION_UNKNOWN_ERROR;

        if (!print)
                return status;

        source = EXTRACT(c_stat, EV6__C_STAT__SOURCE);
        stream = EXTRACT(c_stat, EV6__C_STAT__ISTREAM);
        bits = EXTRACT(c_stat, EV6__C_STAT__DOUBLE);

        if (c_stat & EV6__C_STAT__BC_PERR) {
                printk("%s    Bcache tag parity error\n", err_print_prefix);
                source = -1;
        }

        if (c_stat & EV6__C_STAT__DC_PERR) {
                printk("%s    Dcache tag parity error\n", err_print_prefix);
                source = -1;
        }

        if (c_stat == EV6__C_STAT__PROBE_BC_ERR0 ||
            c_stat == EV6__C_STAT__PROBE_BC_ERR1) {
                printk("%s    Bcache single-bit error on a probe hit\n",
                       err_print_prefix);
                source = -1;
        }

        if (source != -1) 
                printk("%s    %s-STREAM %s-BIT ECC error from %s\n",
                       err_print_prefix,
                       streamname[stream], bitsname[bits], sourcename[source]);

        printk("%s    Address: 0x%016llx\n"
                 "    Syndrome[upper.lower]: %02llx.%02llx\n",
               err_print_prefix,
               c_addr,
               c2_syn, c1_syn);

        if (source == EV6__C_STAT__SOURCE_MEMORY ||
            source == EV6__C_STAT__SOURCE_BCACHE) 
                printk("%s    Block status: %s%s%s%s\n",
                       err_print_prefix,
                       (c_sts & EV6__C_STS__SHARED) ? "SHARED " : "",
                       (c_sts & EV6__C_STS__DIRTY)  ? "DIRTY "  : "",
                       (c_sts & EV6__C_STS__VALID)  ? "VALID "  : "",
                       (c_sts & EV6__C_STS__PARITY) ? "PARITY " : "");
                
        return status;
}

void
ev6_register_error_handlers(void)
{
        /* None right now. */
}

int
ev6_process_logout_frame(struct el_common *mchk_header, int print)
{
        struct el_common_EV6_mcheck *ev6mchk = 
                (struct el_common_EV6_mcheck *)mchk_header;
        int status = MCHK_DISPOSITION_UNKNOWN_ERROR;

        status |= ev6_parse_ibox(ev6mchk->I_STAT, print);
        status |= ev6_parse_mbox(ev6mchk->MM_STAT, ev6mchk->DC_STAT, 
                                 ev6mchk->C_STAT, print);
        status |= ev6_parse_cbox(ev6mchk->C_ADDR, ev6mchk->DC1_SYNDROME,
                                 ev6mchk->DC0_SYNDROME, ev6mchk->C_STAT,
                                 ev6mchk->C_STS, print);

        if (!print)
                return status;

        if (status != MCHK_DISPOSITION_DISMISS) {
                char *saved_err_prefix = err_print_prefix;

                /*
                 * Dump some additional information from the frame
                 */
                printk("%s    EXC_ADDR: 0x%016lx   IER_CM: 0x%016lx"
                            "   ISUM: 0x%016lx\n"
                         "    PAL_BASE: 0x%016lx   I_CTL:  0x%016lx"
                            "   PCTX: 0x%016lx\n",
                       err_print_prefix,
                       ev6mchk->EXC_ADDR, ev6mchk->IER_CM, ev6mchk->ISUM,
                       ev6mchk->PAL_BASE, ev6mchk->I_CTL, ev6mchk->PCTX);

                if (status == MCHK_DISPOSITION_UNKNOWN_ERROR) {
                        printk("%s    UNKNOWN error, frame follows:\n",
                               err_print_prefix);
                } else {
                        /* had decode -- downgrade print level for frame */
                        err_print_prefix = KERN_NOTICE;
                }

                mchk_dump_logout_frame(mchk_header);

                err_print_prefix = saved_err_prefix;
        }

        return status;
}

void
ev6_machine_check(unsigned long vector, unsigned long la_ptr)
{
        struct el_common *mchk_header = (struct el_common *)la_ptr;

        /*
         * Sync the processor
         */
        mb();
        draina();

        /*
         * Parse the logout frame without printing first. If the only error(s)
         * found are have a disposition of "dismiss", then just dismiss them
         * and don't print any message
         */
        if (ev6_process_logout_frame(mchk_header, 0) != 
            MCHK_DISPOSITION_DISMISS) {
                char *saved_err_prefix = err_print_prefix;
                err_print_prefix = KERN_CRIT;

                /*
                 * Either a nondismissable error was detected or no
                 * recognized error was detected  in the logout frame 
                 * -- report the error in either case
                 */
                printk("%s*CPU %s Error (Vector 0x%x) reported on CPU %d:\n", 
                       err_print_prefix,
                       (vector == SCB_Q_PROCERR)?"Correctable":"Uncorrectable",
                       (unsigned int)vector, (int)smp_processor_id());
                
                ev6_process_logout_frame(mchk_header, 1);
                dik_show_regs(get_irq_regs(), NULL);

                err_print_prefix = saved_err_prefix;
        }

        /* 
         * Release the logout frame 
         */
        wrmces(0x7);
        mb();
}