git: e627e25d761f - main - xen/xenpv: remove low memory limit for non-x86

[Roger Pau Monné]

The branch main has been updated by royger:

URL: https://cgit.FreeBSD.org/src/commit/?id=e627e25d761f8a11e9e5881e804fae5793404947

commit e627e25d761f8a11e9e5881e804fae5793404947
Author:     Elliott Mitchell <ehem+freebsd at m5p.com>
AuthorDate: 2021-04-06 09:28:38 +0000
Commit:     Roger Pau Monné <royger at FreeBSD.org>
CommitDate: 2021-07-28 15:27:03 +0000

    xen/xenpv: remove low memory limit for non-x86
    
    For embedded devices reserved addresses will be known in advance.  More
    recently added devices will also likely be correctly updated.  As a
    result using any available address is reasonable on non-x86.
    
    Reviewed by: royger
    Differential Revision: https://reviews.freebsd.org/D29304
---
 sys/dev/xen/bus/xenpv.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sys/dev/xen/bus/xenpv.c b/sys/dev/xen/bus/xenpv.c
index 080c82c73f08..42f2c88a2885 100644
--- a/sys/dev/xen/bus/xenpv.c
+++ b/sys/dev/xen/bus/xenpv.c
@@ -55,13 +55,17 @@ __FBSDID("$FreeBSD$");
  *
  * Since this is not possible on i386 just use any available memory
  * chunk above 1MB and hope we don't clash with anything else.
+ *
+ * Other architectures better document MMIO regions and drivers more
+ * reliably reserve them.  As such, allow using any unpopulated memory
+ * region.
  */
 #ifdef __amd64__
 #define LOW_MEM_LIMIT	0x100000000ul
 #elif defined(__i386__)
 #define LOW_MEM_LIMIT	0x100000ul
 #else
-#error "Unsupported architecture"
+#define LOW_MEM_LIMIT	0
 #endif
 
 static devclass_t xenpv_devclass;