[src/bouyer-xenpvh]: src/sys/arch/xen/xen Use some PIO magic to disable qemu ...

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

details:   https://anonhg.NetBSD.org/src/rev/9ecd15ddac83
branches:  bouyer-xenpvh
changeset: 982920:9ecd15ddac83
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sat Apr 11 21:21:16 2020 +0000

description:
Use some PIO magic to disable qemu emulated disks and network device
when PVHVM is configured. From FreeBSD.

diffstat:

 sys/arch/xen/xen/hypervisor.c |  23 ++++++++++++++++++++---
 1 files changed, 20 insertions(+), 3 deletions(-)

diffs (65 lines):

diff -r 9f2a8937abcc -r 9ecd15ddac83 sys/arch/xen/xen/hypervisor.c
--- a/sys/arch/xen/xen/hypervisor.c     Sat Apr 11 18:26:06 2020 +0000
+++ b/sys/arch/xen/xen/hypervisor.c     Sat Apr 11 21:21:16 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: hypervisor.c,v 1.73.2.1 2020/04/08 17:59:17 bouyer Exp $ */
+/* $NetBSD: hypervisor.c,v 1.73.2.2 2020/04/11 21:21:16 bouyer Exp $ */
 
 /*
  * Copyright (c) 2005 Manuel Bouyer.
@@ -53,7 +53,7 @@
 
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: hypervisor.c,v 1.73.2.1 2020/04/08 17:59:17 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: hypervisor.c,v 1.73.2.2 2020/04/11 21:21:16 bouyer Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -73,6 +73,7 @@
 #include <xen/hypervisor.h>
 #include <xen/evtchn.h>
 #include <xen/include/public/version.h>
+#include <x86//pio.h>
 
 #include <sys/cpu.h>
 #include <sys/dirent.h>
@@ -191,6 +192,15 @@
 static bool hypervisor_suspend(device_t, const pmf_qual_t *);
 static bool hypervisor_resume(device_t, const pmf_qual_t *);
 
+/* from FreeBSD */
+#define XEN_MAGIC_IOPORT 0x10
+enum {
+       XMI_MAGIC                        = 0x49d2,
+       XMI_UNPLUG_IDE_DISKS             = 0x01,
+       XMI_UNPLUG_NICS                  = 0x02,
+       XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04
+}; 
+
 /*
  * Probe for the hypervisor; always succeeds.
  */
@@ -415,7 +425,7 @@
        bi.common.len = sizeof(struct btinfo_rootdevice);
 
        /* From i386/multiboot.c */
-       /*      $NetBSD: hypervisor.c,v 1.73.2.1 2020/04/08 17:59:17 bouyer Exp $       */
+       /*      $NetBSD: hypervisor.c,v 1.73.2.2 2020/04/11 21:21:16 bouyer Exp $       */
        int i, len;
        vaddr_t data;
        extern struct bootinfo  bootinfo;
@@ -434,6 +444,13 @@
                bip->bi_nentries++;
        }
 
+       /* disable emulated devices */
+       if (inw(XEN_MAGIC_IOPORT) == XMI_MAGIC) {
+               outw(XEN_MAGIC_IOPORT, XMI_UNPLUG_IDE_DISKS | XMI_UNPLUG_NICS);
+       } else {
+               aprint_error("%s: Unable to disable emulated devices\n",
+                   haa->haa_busname);
+       }
 #endif /* XENPVHVM */
 
        /* If we got here, it must mean we matched */