/* $NetBSD: pvh_consinit.c,v 1.6 2023/10/17 13:27:58 bouyer Exp $ */

/*
* Copyright (c) 2020 Manuel Bouyer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pvh_consinit.c,v 1.6 2023/10/17 13:27:58 bouyer Exp $");

#include "xencons.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <uvm/uvm_extern.h>
#include <uvm/uvm_prot.h>

#include <dev/cons.h>
#include <xen/xen.h>
#include <xen/hypervisor.h>
#include <xen/include/public/hvm/hvm_op.h>
#include <xen/include/public/hvm/params.h>

#include "xen_def_cons.h"

int
xen_pvh_consinit(void)
{
       /*
        * hugly hack because we're called multiple times at different
        * boot stage.
        */
       static int initted = 0;

       if (initted == 0) {
               /* fall back to printk() until we can setup our console */
               xen_early_console();
       }
       if (xendomain_is_dom0()) {
               union xen_cmdline_parseinfo xcp;
               xen_parse_cmdline(XEN_PARSE_CONSOLE, &xcp);
#ifdef CONS_OVERRIDE
               if (strcmp(default_consinfo.devname, "tty0") == 0 ||
                   strcmp(default_consinfo.devname, "pc") == 0) {
#else
               if (strcmp(xcp.xcp_console, "tty0") == 0 || /* linux name */
                   strcmp(xcp.xcp_console, "pc") == 0) { /* NetBSD name */
#endif /* CONS_OVERRIDE */
                       initted++;
                       return 0; /* native console code will do it */
               }
       }
       if (initted == 0 && !xendomain_is_dom0()) {
               /* pmap not up yet */
               initted++;
               return 1;
       } else if (initted > 1) {
               return 1;
       }
       initted++;
       if (xendomain_is_dom0()) {
               /* we know we're using Xen's console at this point */
               xenconscn_attach(); /* no ring in this case */
               initted++; /* don't init console twice */
               return 1;
       }

#if NXENCONS > 0
       /* we can now map the xencons rings. */
       struct xen_hvm_param xen_hvm_param;


       xen_hvm_param.domid = DOMID_SELF;
       xen_hvm_param.index = HVM_PARAM_CONSOLE_PFN;

       if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
               panic("xen_pvh_consinit: can't get console PFN");

       xen_start_info.console.domU.mfn = xen_hvm_param.value;
       pmap_kenter_pa((vaddr_t) xencons_interface, ptoa(xen_hvm_param.value),
           VM_PROT_READ|VM_PROT_WRITE, 0);

       xen_hvm_param.domid = DOMID_SELF;
       xen_hvm_param.index = HVM_PARAM_CONSOLE_EVTCHN;

       if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
               panic("xen_pvh_consinit: can't get console event");

       xen_start_info.console.domU.evtchn = xen_hvm_param.value;
       xenconscn_attach();
#endif
       return 1;
}