1/* $NetBSD: pvh_consinit.c,v 1.6 2023/10/17 13:27:58 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 1.6 2023/10/17 13:27:58 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#include "xen_def_cons.h"
45
46int
47xen_pvh_consinit(void)
48{
49	/*
50	 * hugly hack because we're called multiple times at different
51	 * boot stage.
52	 */
53	static int initted = 0;
54
55	if (initted == 0) {
56		/* fall back to printk() until we can setup our console */
57		xen_early_console();
58	}
59	if (xendomain_is_dom0()) {
60		union xen_cmdline_parseinfo xcp;
61		xen_parse_cmdline(XEN_PARSE_CONSOLE, &xcp);
62#ifdef CONS_OVERRIDE
63                if (strcmp(default_consinfo.devname, "tty0") == 0 ||
64		    strcmp(default_consinfo.devname, "pc") == 0) {
65#else
66		if (strcmp(xcp.xcp_console, "tty0") == 0 || /* linux name */
67		    strcmp(xcp.xcp_console, "pc") == 0) { /* NetBSD name */
68#endif /* CONS_OVERRIDE */
69			initted++;
70			return 0; /* native console code will do it */
71		}
72	}
73	if (initted == 0 && !xendomain_is_dom0()) {
74		/* pmap not up yet */
75		initted++;
76		return 1;
77	} else if (initted > 1) {
78		return 1;
79	}
80	initted++;
81	if (xendomain_is_dom0()) {
82		/* we know we're using Xen's console at this point */
83		xenconscn_attach(); /* no ring in this case */
84		initted++; /* don't init console twice */
85		return 1;
86	}
87
88#if NXENCONS > 0
89	/* we can now map the xencons rings. */
90	struct xen_hvm_param xen_hvm_param;
91
92
93	xen_hvm_param.domid = DOMID_SELF;
94	xen_hvm_param.index = HVM_PARAM_CONSOLE_PFN;
95
96	if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
97		panic("xen_pvh_consinit: can't get console PFN");
98
99	xen_start_info.console.domU.mfn = xen_hvm_param.value;
100	pmap_kenter_pa((vaddr_t) xencons_interface, ptoa(xen_hvm_param.value),
101	    VM_PROT_READ|VM_PROT_WRITE, 0);
102
103	xen_hvm_param.domid = DOMID_SELF;
104	xen_hvm_param.index = HVM_PARAM_CONSOLE_EVTCHN;
105
106	if ( HYPERVISOR_hvm_op(HVMOP_get_param, &xen_hvm_param) < 0)
107		panic("xen_pvh_consinit: can't get console event");
108
109	xen_start_info.console.domU.evtchn = xen_hvm_param.value;
110	xenconscn_attach();
111#endif
112	return 1;
113}
114