/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef __xpv
#error "This file is for i86xpv only"
#endif

#include <sys/types.h>
#include <sys/mca_x86.h>
#include <sys/archsystm.h>
#include <sys/hypervisor.h>

#include "../../i86pc/cpu/generic_cpu/gcpu.h"

extern xpv_mca_panic_data_t *xpv_mca_panic_data;

mc_info_t gcpu_mce_data;

enum mctelem_direction {
        MCTELEM_FORWARD,
        MCTELEM_REVERSE
};

static uint32_t gcpu_xpv_hdl_lookupfails;
static uint32_t gcpu_xpv_bankhdr_found;
static uint32_t gcpu_xpv_spechdr_found;

static uint32_t gcpu_xpv_mca_hcall_fails[16];
static uint32_t gcpu_xpv_globalhdr_found;

static cmi_mca_regs_t *gcpu_xpv_bankregs;
size_t gcpu_xpv_bankregs_sz;

#define GCPU_XPV_ARCH_NREGS     3

void
gcpu_xpv_mca_init(int nbanks)
{
        if (gcpu_xpv_bankregs == NULL) {
                gcpu_xpv_bankregs_sz = nbanks * GCPU_XPV_ARCH_NREGS *
                    sizeof (cmi_mca_regs_t);

                gcpu_xpv_bankregs = kmem_zalloc(gcpu_xpv_bankregs_sz, KM_SLEEP);
        }
}

static void
gcpu_xpv_proxy_logout(int what, struct mc_info *mi, struct mcinfo_common **micp,
    int *idxp, cmi_mca_regs_t *bankregs, size_t bankregs_sz)
{
        struct mcinfo_global *mgi = (struct mcinfo_global *)(uintptr_t)*micp;
        struct mcinfo_common *mic;
        struct mcinfo_bank *mib;
        cmi_hdl_t hdl = NULL;
        cmi_mca_regs_t *mcrp;
        int idx = *idxp;
        int tried = 0;
        int j;

        /* Skip over the MC_TYPE_GLOBAL record */
        ASSERT(mgi->common.type == MC_TYPE_GLOBAL);
        mcrp = NULL;
        mic = x86_mcinfo_next((struct mcinfo_common *)(uintptr_t)mgi);
        idx++;

        /*
         * Process all MC_TYPE_BANK and MC_TYPE_EXTENDED records that
         * follow the MC_TYPE_GLOBAL record, ending when we reach any
         * other record type or when we're out of record.
         *
         * We skip over MC_TYPE_EXTENDED for now - nothing consumes
         * the extended MSR data even in native Solaris.
         */
        while (idx < x86_mcinfo_nentries(mi) &&
            (mic->type == MC_TYPE_BANK || mic->type == MC_TYPE_EXTENDED)) {
                if (mic->type == MC_TYPE_EXTENDED) {
                        gcpu_xpv_spechdr_found++;
                        goto next_record;
                } else {
                        gcpu_xpv_bankhdr_found++;
                }

                if (hdl == NULL && !tried++) {
                        if ((hdl = cmi_hdl_lookup(CMI_HDL_SOLARIS_xVM_MCA,
                            mgi->mc_socketid, mgi->mc_coreid,
                            mgi->mc_core_threadid)) == NULL) {
                                gcpu_xpv_hdl_lookupfails++;
                                goto next_record;
                        } else {
                                bzero(bankregs, bankregs_sz);
                                mcrp = bankregs;
                        }
                }

                mib = (struct mcinfo_bank *)(uintptr_t)mic;

                mcrp->cmr_msrnum = IA32_MSR_MC(mib->mc_bank, STATUS);
                mcrp->cmr_msrval = mib->mc_status;
                mcrp++;

                mcrp->cmr_msrnum = IA32_MSR_MC(mib->mc_bank, ADDR);
                mcrp->cmr_msrval = mib->mc_addr;
                mcrp++;

                mcrp->cmr_msrnum = IA32_MSR_MC(mib->mc_bank, MISC);
                mcrp->cmr_msrval = mib->mc_misc;
                mcrp++;

next_record:
                idx++;
                mic = x86_mcinfo_next(mic);
        }

        /*
         * If we found some telemetry and a handle to associate it with
         * then "forward" that telemetry into the MSR interpose layer
         * and then request logout which will find that interposed
         * telemetry.  Indicate that logout code should clear bank
         * status registers so that it can invalidate them in the interpose
         * layer - they won't actually make it as far as real MSR writes.
         */
        if (hdl != NULL) {
                cmi_mca_regs_t gsr;
                gcpu_mce_status_t mce;

                gsr.cmr_msrnum = IA32_MSR_MCG_STATUS;
                gsr.cmr_msrval = mgi->mc_gstatus;
                cmi_hdl_msrforward(hdl, &gsr, 1);

                cmi_hdl_msrforward(hdl, bankregs, mcrp - bankregs);
                gcpu_mca_logout(hdl, NULL, (uint64_t)-1, &mce, B_TRUE, what);
                cmi_hdl_rele(hdl);
        }

        /*
         * We must move the index on at least one record or our caller
         * may loop forever;  our initial increment over the global
         * record assures this.
         */
        ASSERT(idx > *idxp);
        *idxp = idx;
        *micp = mic;
}

/*
 * Process a struct mc_info.
 *
 * There are x86_mcinfo_nentries(mi) entries.  An entry of type
 * MC_TYPE_GLOBAL precedes a number (potentially zero) of
 * entries of type MC_TYPE_BANK for telemetry from MCA banks
 * of the resource identified in the MC_TYPE_GLOBAL entry.
 * I think there can be multiple MC_TYPE_GLOBAL entries per buffer.
 */
void
gcpu_xpv_mci_process(mc_info_t *mi, int type,
    cmi_mca_regs_t *bankregs, size_t bankregs_sz)
{
        struct mcinfo_common *mic;
        int idx;

        mic = x86_mcinfo_first(mi);

        idx = 0;
        while (idx < x86_mcinfo_nentries(mi)) {
                if (mic->type == MC_TYPE_GLOBAL) {
                        gcpu_xpv_globalhdr_found++;
                        gcpu_xpv_proxy_logout(type == XEN_MC_URGENT ?
                            GCPU_MPT_WHAT_MC_ERR : GCPU_MPT_WHAT_XPV_VIRQ,
                            mi, &mic, &idx, bankregs, bankregs_sz);
                } else {
                        idx++;
                        mic = x86_mcinfo_next(mic);
                }
        }
}

int
gcpu_xpv_telem_read(mc_info_t *mci, int type, uint64_t *idp)
{
        xen_mc_t xmc;
        xen_mc_fetch_t *mcf = &xmc.u.mc_fetch;
        long err;

        mcf->flags = type;
        set_xen_guest_handle(mcf->data, mci);

        if ((err = HYPERVISOR_mca(XEN_MC_fetch, &xmc)) != 0) {
                gcpu_xpv_mca_hcall_fails[err < 16 ? err : 0]++;
                return (0);
        }

        if (mcf->flags == XEN_MC_OK) {
                *idp = mcf->fetch_id;
                return (1);
        } else {
                *idp = 0;
                return (0);
        }
}

void
gcpu_xpv_telem_ack(int type, uint64_t fetch_id)
{
        xen_mc_t xmc;
        struct xen_mc_fetch *mcf = &xmc.u.mc_fetch;

        mcf->flags = type | XEN_MC_ACK;
        mcf->fetch_id = fetch_id;
        (void) HYPERVISOR_mca(XEN_MC_fetch, &xmc);
}

static void
mctelem_traverse(void *head, enum mctelem_direction direction,
    boolean_t urgent)
{
        char *tep = head, **ntepp;
        int noff = (direction == MCTELEM_FORWARD) ?
            xpv_mca_panic_data->mpd_fwdptr_offset :
            xpv_mca_panic_data->mpd_revptr_offset;


        while (tep != NULL) {
                struct mc_info **mcip = (struct mc_info **)
                    (tep + xpv_mca_panic_data->mpd_dataptr_offset);

                gcpu_xpv_mci_process(*mcip,
                    urgent ? XEN_MC_URGENT : XEN_MC_NONURGENT,
                    gcpu_xpv_bankregs, gcpu_xpv_bankregs_sz);

                ntepp = (char **)(tep + noff);
                tep = *ntepp;
        }
}

/*
 * Callback made from panicsys.  We may have reached panicsys from a
 * Solaris-initiated panic or a hypervisor-initiated panic;  for the
 * latter we may not perform any hypercalls.  Our task is to retrieve
 * unprocessed MCA telemetry from the hypervisor and shovel it into
 * errorqs for later processing during panic.
 */
void
gcpu_xpv_panic_callback(void)
{
        if (IN_XPV_PANIC()) {
                xpv_mca_panic_data_t *ti = xpv_mca_panic_data;

                if (ti == NULL ||
                    ti->mpd_magic != MCA_PANICDATA_MAGIC ||
                    ti->mpd_version != MCA_PANICDATA_VERS)
                        return;

                mctelem_traverse(ti->mpd_urgent_processing, MCTELEM_FORWARD,
                    B_TRUE);
                mctelem_traverse(ti->mpd_urgent_dangling, MCTELEM_REVERSE,
                    B_TRUE);
                mctelem_traverse(ti->mpd_urgent_committed, MCTELEM_REVERSE,
                    B_TRUE);

                mctelem_traverse(ti->mpd_nonurgent_processing, MCTELEM_FORWARD,
                    B_FALSE);
                mctelem_traverse(ti->mpd_nonurgent_dangling, MCTELEM_REVERSE,
                    B_FALSE);
                mctelem_traverse(ti->mpd_nonurgent_committed, MCTELEM_REVERSE,
                    B_FALSE);
        } else {
                int types[] = { XEN_MC_URGENT, XEN_MC_NONURGENT };
                uint64_t fetch_id;
                int i;

                for (i = 0; i < sizeof (types) / sizeof (types[0]); i++) {
                        while (gcpu_xpv_telem_read(&gcpu_mce_data,
                            types[i], &fetch_id)) {
                                gcpu_xpv_mci_process(&gcpu_mce_data, types[i],
                                    gcpu_xpv_bankregs, gcpu_xpv_bankregs_sz);
                                gcpu_xpv_telem_ack(types[i], fetch_id);
                        }
                }
        }
}