# HG changeset patch
# User Isaku Yamahata <yamahata@xxxxxxxxxxxxx>
# Date 1213241021 -32400
# Node ID d84baff75387166913985a705b5ea91e909406b3
# Parent  b477fb2022639b1e7d9832d6433e234176d5fb6f
[IA64] readd efi support to acpi_os_get_root_pointer()

On ia64 RSDP address is obtained from efi table instead of
memory scan. Otherwise it may use wrong table to fail to find
tables.

Signed-off-by: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>

diff --git a/xen/drivers/acpi/osl.c b/xen/drivers/acpi/osl.c
--- a/xen/drivers/acpi/osl.c
+++ b/xen/drivers/acpi/osl.c
@@ -37,6 +37,9 @@
 #include <acpi/platform/aclinux.h>
 #include <xen/spinlock.h>
 #include <xen/domain_page.h>
+#ifdef __ia64__
+#include <linux/efi.h>
+#endif
 
 #define _COMPONENT		ACPI_OS_SERVICES
 ACPI_MODULE_NAME("osl")
@@ -82,9 +85,25 @@
 
 acpi_physical_address __init acpi_os_get_root_pointer(void)
 {
-	acpi_physical_address pa = 0;
-	acpi_find_root_pointer(&pa);
-	return pa;
+#ifdef __ia64__
+	if (efi_enabled) {
+		if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
+			return efi.acpi20;
+		else if (efi.acpi != EFI_INVALID_TABLE_ADDR)
+			return efi.acpi;
+		else {
+			printk(KERN_ERR PREFIX
+			       "System description tables not found\n");
+			return 0;
+		}
+	} else
+#endif
+	{
+		acpi_physical_address pa = 0;
+
+		acpi_find_root_pointer(&pa);
+		return pa;
+	}
 }
 
 void __iomem *
diff --git a/xen/include/asm-ia64/config.h b/xen/include/asm-ia64/config.h
--- a/xen/include/asm-ia64/config.h
+++ b/xen/include/asm-ia64/config.h
@@ -17,6 +17,7 @@
 // this needs to be on to run on system with large memory hole
 #define	CONFIG_VIRTUAL_FRAME_TABLE
 
+#define CONFIG_EFI
 #define CONFIG_EFI_PCDP
 #define CONFIG_SERIAL_SGI_L1_CONSOLE