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pvh_consinit.c revision 1.3 
      1 /* $NetBSD: pvh_consinit.c,v 1.3 2023/03/24 12:28:42 bouyer Exp $ */
      2 
      3 /*
      4  * Copyright (c) 2020 Manuel Bouyer.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     25  *
     26  */
     27 
     28 #include <sys/cdefs.h>
     29 __KERNEL_RCSID(0, "$NetBSD: pvh_consinit.c,v 1.3 2023/03/24 12:28:42 bouyer Exp $");
     30 
     31 #include "xencons.h"
     32 #include <sys/param.h>
     33 #include <sys/systm.h>
     34 #include <sys/device.h>
     35 #include <uvm/uvm_extern.h>
     36 #include <uvm/uvm_prot.h>
     37 
     38 #include <dev/cons.h>
     39 #include <xen/xen.h>
     40 #include <xen/hypervisor.h>
     41 #include <xen/include/public/hvm/hvm_op.h>
     42 #include <xen/include/public/hvm/params.h>
     43 
     44 static int pvh_xenconscn_getc(dev_t);
     45 static void pvh_xenconscn_putc(dev_t, int);
     46 static void pvh_xenconscn_pollc(dev_t, int);
     47 
     48 static struct consdev pvh_xencons = {
     49         NULL, NULL, pvh_xenconscn_getc, pvh_xenconscn_putc, pvh_xenconscn_pollc,
     50 	NULL, NULL, NULL, NODEV, CN_NORMAL
     51 };
     52 
     53 
     54 int
     55 xen_pvh_consinit(void)
     56 {
     57 	/*
     58 	 * hugly hack because we're called multiple times at different
     59 	 * boot stage.
     60 	 */
     61 	static int initted = 0;
     62 	if (xendomain_is_dom0()) {
     63 		union xen_cmdline_parseinfo xcp;
     64 		xen_parse_cmdline(XEN_PARSE_CONSOLE, &xcp);
     65 #ifdef CONS_OVERRIDE
     66                 if (strcmp(default_consinfo.devname, "tty0") == 0 ||
     67 		    strcmp(default_consinfo.devname, "pc") == 0) {
     68 #else
     69 		if (strcmp(xcp.xcp_console, "tty0") == 0 || /* linux name */
     70 		    strcmp(xcp.xcp_console, "pc") == 0) { /* NetBSD name */
     71 #endif /* CONS_OVERRIDE */
     72 			return 0; /* native console code will do it */
     73 		}
     74 	}
     75 	if (initted == 0 && !xendomain_is_dom0()) {
     76 		/* pmap not up yet, fall back to printk() */
     77 		cn_tab = &pvh_xencons;
     78 		initted++;
     79 		return 1;
     80 	} else if (initted > 1) {
     81 		return 1;
     82 	}
     83 	initted++;
     84 	if (xendomain_is_dom0()) {
     85 		/* we know we're using Xen's console at this point */
     86 		xenconscn_attach(); /* no ring in this case */
     87 		initted++; /* don't init console twice */
     88 		return 1;
     89 	}
     90 
     91 #if NXENCONS > 0
     92 	/* we can now map the xencons rings. */
     93 	struct xen_hvm_param xen_hvm_param;
     94 
     95 
     96 	xen_hvm_param.domid = DOMID_SELF;
     97 	xen_hvm_param.index = HVM_PARAM_CONSOLE_PFN;
     98 
     99 	if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
    100 		panic("xen_pvh_consinit: can't get console PFN");
    101 
    102 	xen_start_info.console.domU.mfn = xen_hvm_param.value;
    103 	pmap_kenter_pa((vaddr_t) xencons_interface, ptoa(xen_hvm_param.value),
    104 	    VM_PROT_READ|VM_PROT_WRITE, 0);
    105 
    106 	xen_hvm_param.domid = DOMID_SELF;
    107 	xen_hvm_param.index = HVM_PARAM_CONSOLE_EVTCHN;
    108 
    109 	if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
    110 		panic("xen_pvh_consinit: can't get console event");
    111 
    112 	xen_start_info.console.domU.evtchn = xen_hvm_param.value;
    113 	xenconscn_attach();
    114 #endif
    115 	return 1;
    116 }
    117 
    118 static int
    119 pvh_xenconscn_getc(dev_t dev)
    120 {
    121 	while(1)
    122 		;
    123 	return -1;
    124 }
    125 
    126 static void
    127 pvh_xenconscn_putc(dev_t dev, int c)
    128 {
    129 	printk("%c", c);
    130 }
    131 
    132 static void
    133 pvh_xenconscn_pollc(dev_t dev, int on)
    134 {
    135 	return;
    136 }
    137