[PATCH RFC 4/8] xen/arm,arm64: move Xen initialization earlier

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 arch/arm/include/asm/xen/hypervisor.h |    6 ++++++
 arch/arm/kernel/setup.c               |    2 ++
 arch/arm/xen/enlighten.c              |   21 ++++++++++++++-------
 arch/arm64/kernel/setup.c             |    2 ++
 4 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/arch/arm/include/asm/xen/hypervisor.h b/arch/arm/include/asm/xen/hypervisor.h
index d7ab99a..17b3ea2 100644
--- a/arch/arm/include/asm/xen/hypervisor.h
+++ b/arch/arm/include/asm/xen/hypervisor.h
@@ -16,4 +16,10 @@ static inline enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
 	return PARAVIRT_LAZY_NONE;
 }
 
+#ifdef CONFIG_XEN
+void xen_early_init(void);
+#else
+static inline void xen_early_init(void) { return; }
+#endif
+
 #endif /* _ASM_ARM_XEN_HYPERVISOR_H */
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 63af9a7..cb7b8e2 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -45,6 +45,7 @@
 #include <asm/cacheflush.h>
 #include <asm/cachetype.h>
 #include <asm/tlbflush.h>
+#include <asm/xen/hypervisor.h>
 
 #include <asm/prom.h>
 #include <asm/mach/arch.h>
@@ -889,6 +890,7 @@ void __init setup_arch(char **cmdline_p)
 
 	arm_dt_init_cpu_maps();
 	psci_init();
+	xen_early_init();
 #ifdef CONFIG_SMP
 	if (is_smp()) {
 		if (!mdesc->smp_init || !mdesc->smp_init()) {
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index c9770ba..14d17ab 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -195,21 +195,19 @@ static void xen_power_off(void)
  * documentation of the Xen Device Tree format.
  */
 #define GRANT_TABLE_PHYSADDR 0
-static int __init xen_guest_init(void)
+void __init xen_early_init(void)
 {
-	struct xen_add_to_physmap xatp;
-	static struct shared_info *shared_info_page = 0;
+	struct resource res;
 	struct device_node *node;
 	int len;
 	const char *s = NULL;
 	const char *version = NULL;
 	const char *xen_prefix = "xen,xen-";
-	struct resource res;
 
 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
 	if (!node) {
 		pr_debug("No Xen support\n");
-		return 0;
+		return;
 	}
 	s = of_get_property(node, "compatible", &len);
 	if (strlen(xen_prefix) + 3  < len &&
@@ -217,10 +215,10 @@ static int __init xen_guest_init(void)
 		version = s + strlen(xen_prefix);
 	if (version == NULL) {
 		pr_debug("Xen version not found\n");
-		return 0;
+		return;
 	}
 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
-		return 0;
+		return;
 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
 	xen_events_irq = irq_of_parse_and_map(node, 0);
 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
@@ -232,6 +230,15 @@ static int __init xen_guest_init(void)
 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
 	else
 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
+}
+
+static int __init xen_guest_init(void)
+{
+	struct xen_add_to_physmap xatp;
+	static struct shared_info *shared_info_page = 0;
+
+	if (!xen_domain())
+		return 0;
 
 	if (!shared_info_page)
 		shared_info_page = (struct shared_info *)
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index add6ea6..e0d438a 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -53,6 +53,7 @@
 #include <asm/traps.h>
 #include <asm/memblock.h>
 #include <asm/psci.h>
+#include <asm/xen/hypervisor.h>
 
 unsigned int processor_id;
 EXPORT_SYMBOL(processor_id);
@@ -267,6 +268,7 @@ void __init setup_arch(char **cmdline_p)
 	unflatten_device_tree();
 
 	psci_init();
+	xen_early_init();
 
 	cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
 #ifdef CONFIG_SMP
-- 
1.7.2.5