Stefano Stabellini
2013-Apr-18 16:03 UTC
[PATCH v2] xen/arm: introduce xen_early_init, use PSCI on xen
Split xen_guest_init in two functions, one of them (xen_early_init) is
going to be called very early from setup_arch.
Change machine_desc->smp_init to xen_smp_init if Xen is present on the
platform. xen_smp_init just sets smp_ops to psci_smp_ops.
XEN selects ARM_PSCI.
This patch is based on "xen/arm: move to mach-virt and support SMP"
(http://marc.info/?l=linux-kernel&m=136629656432231&w=2)
and "arm: introduce psci_smp_ops"
(http://marc.info/?l=linux-kernel&m=136629750732674&w=2).
Changes in v2:
- fix missing return value for xen_smp_init ifndef CONFIG_SMP.
A git tag for this patch is available here:
git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen.git
3.9-rc3-psci-xen-2-tag
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: xen-devel@lists.xensource.com
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: will.deacon@arm.com
CC: arnd@arndb.de
CC: nicolas.pitre@linaro.org
CC: rob.herring@calxeda.com
CC: linux@arm.linux.org.uk
CC: olof@lixom.net
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
arch/arm/Kconfig | 1 +
arch/arm/include/asm/xen/hypervisor.h | 6 +++++
arch/arm/kernel/setup.c | 3 ++
arch/arm/xen/enlighten.c | 39 ++++++++++++++++++++++++++------
4 files changed, 41 insertions(+), 8 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2c3bdce..344e299 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1892,6 +1892,7 @@ config XEN
depends on ARM && AEABI && OF
depends on CPU_V7 && !CPU_V6
depends on !GENERIC_ATOMIC64
+ select ARM_PSCI
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
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 22cc863..3dcd357 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -55,6 +55,8 @@
#include <asm/unwind.h>
#include <asm/memblock.h>
#include <asm/virt.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/xen.h>
#include "atags.h"
#include "tcm.h"
@@ -768,6 +770,7 @@ 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 b002822..c1fe6f3 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -11,6 +11,8 @@
#include <xen/xenbus.h>
#include <xen/page.h>
#include <xen/xen-ops.h>
+#include <asm/mach/arch.h>
+#include <asm/psci.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include <linux/interrupt.h>
@@ -176,11 +178,36 @@ static int __init xen_secondary_init(unsigned int cpu)
return 0;
}
+static bool __init xen_smp_init(void)
+{
+#ifdef CONFIG_SMP
+ /* If we are running on Xen, use PSCI if available.
+ * In any case do not try to use the native smp_ops. */
+ if (psci_smp_available())
+ smp_set_ops(&psci_smp_ops);
+#endif
+ return true;
+}
+
/*
* see Documentation/devicetree/bindings/arm/xen.txt for the
* documentation of the Xen Device Tree format.
*/
#define GRANT_TABLE_PHYSADDR 0
+void __init xen_early_init(void)
+{
+ struct device_node *node;
+
+ node = of_find_compatible_node(NULL, NULL, "xen,xen");
+ if (!node) {
+ pr_debug("No Xen support\n");
+ return;
+ }
+
+ xen_domain_type = XEN_HVM_DOMAIN;
+ machine_desc->smp_init = xen_smp_init;
+}
+
static int __init xen_guest_init(void)
{
struct xen_add_to_physmap xatp;
@@ -194,25 +221,21 @@ static int __init xen_guest_init(void)
int i;
node = of_find_compatible_node(NULL, NULL, "xen,xen");
- if (!node) {
- pr_debug("No Xen support\n");
- return 0;
- }
+
s = of_get_property(node, "compatible", &len);
if (strlen(xen_prefix) + 3 < len &&
!strncmp(xen_prefix, s, strlen(xen_prefix)))
version = s + strlen(xen_prefix);
if (version == NULL) {
- pr_debug("Xen version not found\n");
- return 0;
+ pr_warn("Xen version not found\n");
+ return -EINVAL;
}
if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
- return 0;
+ return -EINVAL;
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",
version, xen_events_irq, xen_hvm_resume_frames);
- xen_domain_type = XEN_HVM_DOMAIN;
xen_setup_features();
if (xen_feature(XENFEAT_dom0))
--
1.7.2.5