[src/trunk]: src/sys/arch Allow a PVH dom0 to use VGA as console: make xen_pv...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/98bf0a2c746c
branches:  trunk
changeset: 374008:98bf0a2c746c
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Fri Mar 24 12:28:42 2023 +0000

description:
Allow a PVH dom0 to use VGA as console: make xen_pvh_consinit() return 1 if
it handles the console and 0 otherwise (especially when console=tty0 or
console=pc is present on the command line).
In consinit() fallback to native console selection if xen_pvh_consinit()
returns 0.

diffstat:

 sys/arch/x86/x86/consinit.c     |   9 +++++----
 sys/arch/xen/include/xen.h      |   4 ++--
 sys/arch/xen/x86/pvh_consinit.c |  29 ++++++++++++++++++++++-------
 3 files changed, 29 insertions(+), 13 deletions(-)

diffs (123 lines):

diff -r 567e1a9e62dd -r 98bf0a2c746c sys/arch/x86/x86/consinit.c
--- a/sys/arch/x86/x86/consinit.c       Fri Mar 24 12:25:28 2023 +0000
+++ b/sys/arch/x86/x86/consinit.c       Fri Mar 24 12:28:42 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: consinit.c,v 1.35 2022/09/05 14:18:51 riastradh Exp $  */
+/*     $NetBSD: consinit.c,v 1.36 2023/03/24 12:28:42 bouyer Exp $     */
 
 /*
  * Copyright (c) 1998
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: consinit.c,v 1.35 2022/09/05 14:18:51 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: consinit.c,v 1.36 2023/03/24 12:28:42 bouyer Exp $");
 
 #include "opt_kgdb.h"
 #include "opt_puc.h"
@@ -173,8 +173,9 @@ consinit(void)
 
 #ifdef XENPVHVM
        if (vm_guest == VM_GUEST_XENPVH) {
-               xen_pvh_consinit();
-               return;
+               if (xen_pvh_consinit() != 0)
+                       return;
+               /* fallback to native console selection, usefull for dom0 PVH */
        }
 #endif
        if (initted)
diff -r 567e1a9e62dd -r 98bf0a2c746c sys/arch/xen/include/xen.h
--- a/sys/arch/xen/include/xen.h        Fri Mar 24 12:25:28 2023 +0000
+++ b/sys/arch/xen/include/xen.h        Fri Mar 24 12:28:42 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: xen.h,v 1.47 2020/05/02 16:44:36 bouyer Exp $  */
+/*     $NetBSD: xen.h,v 1.48 2023/03/24 12:28:42 bouyer Exp $  */
 
 /*
  *
@@ -60,7 +60,7 @@ void  xen_parse_cmdline(int, union xen_cm
 
 void   xenconscn_attach(void);
 
-void   xen_pvh_consinit(void);
+int    xen_pvh_consinit(void);
 
 void   xenprivcmd_init(void);
 
diff -r 567e1a9e62dd -r 98bf0a2c746c sys/arch/xen/x86/pvh_consinit.c
--- a/sys/arch/xen/x86/pvh_consinit.c   Fri Mar 24 12:25:28 2023 +0000
+++ b/sys/arch/xen/x86/pvh_consinit.c   Fri Mar 24 12:28:42 2023 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: pvh_consinit.c,v 1.2 2020/05/03 17:23:14 bouyer Exp $ */
+/* $NetBSD: pvh_consinit.c,v 1.3 2023/03/24 12:28:42 bouyer Exp $ */
 
 /*
  * Copyright (c) 2020 Manuel Bouyer.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pvh_consinit.c,v 1.2 2020/05/03 17:23:14 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pvh_consinit.c,v 1.3 2023/03/24 12:28:42 bouyer Exp $");
 
 #include "xencons.h"
 #include <sys/param.h>
@@ -51,7 +51,7 @@ static struct consdev pvh_xencons = {
 };
 
 
-void
+int
 xen_pvh_consinit(void)
 {
        /*
@@ -59,21 +59,35 @@ xen_pvh_consinit(void)
         * boot stage.
         */
        static int initted = 0;
+       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 */
+                       return 0; /* native console code will do it */
+               }
+       }
        if (initted == 0 && !xendomain_is_dom0()) {
                /* pmap not up yet, fall back to printk() */
                cn_tab = &pvh_xencons;
                initted++;
-               return;
+               return 1;
        } else if (initted > 1) {
-               return;
+               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;
+               return 1;
        }
-               
+
 #if NXENCONS > 0
        /* we can now map the xencons rings. */
        struct xen_hvm_param xen_hvm_param;
@@ -98,6 +112,7 @@ xen_pvh_consinit(void)
        xen_start_info.console.domU.evtchn = xen_hvm_param.value;
        xenconscn_attach();
 #endif
+       return 1;
 }
 
 static int