xen: add macro for version number string

On Arm64 Linux kernel prints log for Xen version number:

  Xen XEN_VERSION.XEN_SUBVERSION support found

The header file "xen/compile.h" is missed so that XEN_VERSION and
XEN_SUBVERSION are not defined, __stringify() wrongly converts them as
strings and concatenate to string "XEN_VERSION.XEN_SUBVERSION".

This patch introduces a string macro XEN_VERSION_STRING, we can directly
use it as version number string, as a result it drops to use of
__stringify() to make the code more readable.

The change has been tested on Ampere AVA Arm64 platform.

Fixes: 5d797ee199 ("xen/arm: split domain_build.c")
Suggested-by: Bertrand Marquis <bertrand.marquis@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

xen/arch/arm/acpi/domain_build.c

@@ -9,6 +9,7 @@
  * GNU General Public License for more details.
  */
 
+#include <xen/compile.h>
 #include <xen/mm.h>
 #include <xen/sched.h>
 #include <xen/acpi.h>
@@ -91,7 +92,7 @@ static int __init acpi_make_hypervisor_node(const struct kernel_info *kinfo,
                                             struct membank tbl_add[])
 {
     const char compat[] =
-        "xen,xen-"__stringify(XEN_VERSION)"."__stringify(XEN_SUBVERSION)"\0"
+        "xen,xen-" XEN_VERSION_STRING "\0"
         "xen,xen";
     int res;
     /* Convenience alias */

xen/arch/arm/domain_build.c

@@ -1367,7 +1367,7 @@ static int __init make_hypervisor_node(struct domain *d,
                                        int addrcells, int sizecells)
 {
     const char compat[] =
-        "xen,xen-"__stringify(XEN_VERSION)"."__stringify(XEN_SUBVERSION)"\0"
+        "xen,xen-" XEN_VERSION_STRING "\0"
         "xen,xen";
     __be32 *reg, *cells;
     gic_interrupt_t intr;

xen/common/efi/boot.c

@@ -1341,8 +1341,8 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
             efi_console_set_mode();
     }
 
-    PrintStr(L"Xen " __stringify(XEN_VERSION) "." __stringify(XEN_SUBVERSION)
-             XEN_EXTRAVERSION " (c/s " XEN_CHANGESET ") EFI loader\r\n");
+    PrintStr(L"Xen " XEN_VERSION_STRING XEN_EXTRAVERSION
+	     " (c/s " XEN_CHANGESET ") EFI loader\r\n");
 
     efi_arch_relocate_image(0);
 

xen/include/xen/compile.h.in

@@ -7,6 +7,7 @@
 
 #define XEN_VERSION		@@version@@
 #define XEN_SUBVERSION		@@subversion@@
+#define XEN_VERSION_STRING	"@@version@@.@@subversion@@"
 #define XEN_EXTRAVERSION	"@@extraversion@@"
 
 #define XEN_CHANGESET		"@@changeset@@"