xref: /netbsd-src/sys/arch/xen/x86/pvh_consinit.c (revision 9c74eb8debad6b459eedfb81988b57fbd47d8d48)
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 
46 int
xen_pvh_consinit(void)47 xen_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