[PATCH v3 0/6] Add support for a fake, para-virtualised machine

[PATCH v3 0/6] Add support for a fake, para-virtualised machine

[Will Deacon]

Hi,

This is version three of the patches originally posted here:

  v1.) http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/135870.html
  v2.) http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/137750.html

Thanks to all those who have provided comments so far.
Changes for v3 include:

	* Ripped out *even more* SMP code by rebasing onto latest
	  mainline
	* Removed function-base property from device-tree binding
	* Annotated the low-level firmware invocation functions with
	  noinline to clarify intent
	* Minor cleanups

As usual, testing this relies on KVM support for PSCI, a magic kvmtool
and Mark Rutland's arch-timer patches.

Comments welcome,

Will


Marc Zyngier (1):
  ARM: Dummy Virtual Machine platform support

Will Deacon (5):
  ARM: opcodes: add missing include of linux/linkage.h
  ARM: opcodes: add opcodes definitions for ARM security extensions
  ARM: psci: add devicetree binding for describing PSCI firmware
  ARM: psci: add support for PSCI invocations from the kernel
  ARM: mach-virt: add SMP support using PSCI

 Documentation/devicetree/bindings/arm/psci.txt |  55 +++++++
 arch/arm/Kconfig                               |  12 ++
 arch/arm/Makefile                              |   1 +
 arch/arm/include/asm/opcodes-sec.h             |  24 +++
 arch/arm/include/asm/opcodes.h                 |   1 +
 arch/arm/include/asm/psci.h                    |  36 +++++
 arch/arm/kernel/Makefile                       |   1 +
 arch/arm/kernel/psci.c                         | 211 +++++++++++++++++++++++++
 arch/arm/mach-virt/Kconfig                     |  10 ++
 arch/arm/mach-virt/Makefile                    |   6 +
 arch/arm/mach-virt/platsmp.c                   |  58 +++++++
 arch/arm/mach-virt/virt.c                      |  69 ++++++++
 12 files changed, 484 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/psci.txt
 create mode 100644 arch/arm/include/asm/opcodes-sec.h
 create mode 100644 arch/arm/include/asm/psci.h
 create mode 100644 arch/arm/kernel/psci.c
 create mode 100644 arch/arm/mach-virt/Kconfig
 create mode 100644 arch/arm/mach-virt/Makefile
 create mode 100644 arch/arm/mach-virt/platsmp.c
 create mode 100644 arch/arm/mach-virt/virt.c

-- 
1.8.0

[PATCH v3 1/6] ARM: opcodes: add missing include of linux/linkage.h

[Will Deacon]

opcodes.h wants to declare an asmlinkage function, so we need to include
linux/linkage.h

Acked-by: Dave Martin <dave.martin-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
---
 arch/arm/include/asm/opcodes.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h
index 74e211a..e796c59 100644
--- a/arch/arm/include/asm/opcodes.h
+++ b/arch/arm/include/asm/opcodes.h
@@ -10,6 +10,7 @@
 #define __ASM_ARM_OPCODES_H
 
 #ifndef __ASSEMBLY__
+#include <linux/linkage.h>
 extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr);
 #endif
 
-- 
1.8.0

[PATCH v3 2/6] ARM: opcodes: add opcodes definitions for ARM security extensions

[Will Deacon]

The ARM security extensions introduced the smc instruction, which is not
supported by all versions of GAS.

This patch introduces opcodes-sec.h, so that smc is made available in a
similar manner to hvc.

Acked-by: Dave Martin <dave.martin-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
---
 arch/arm/include/asm/opcodes-sec.h | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 arch/arm/include/asm/opcodes-sec.h

diff --git a/arch/arm/include/asm/opcodes-sec.h b/arch/arm/include/asm/opcodes-sec.h
new file mode 100644
index 0000000..bc3a917
--- /dev/null
+++ b/arch/arm/include/asm/opcodes-sec.h
@@ -0,0 +1,24 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#ifndef __ASM_ARM_OPCODES_SEC_H
+#define __ASM_ARM_OPCODES_SEC_H
+
+#include <asm/opcodes.h>
+
+#define __SMC(imm4) __inst_arm_thumb32(					\
+	0xE1600070 | (((imm4) & 0xF) << 0),				\
+	0xF7F08000 | (((imm4) & 0xF) << 16)				\
+)
+
+#endif /* __ASM_ARM_OPCODES_SEC_H */
-- 
1.8.0

[PATCH v3 3/6] ARM: psci: add devicetree binding for describing PSCI firmware

[Will Deacon]

This patch adds a new devicetree binding for describing PSCI firmware
to Linux.

Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
---
 Documentation/devicetree/bindings/arm/psci.txt | 55 ++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/psci.txt

diff --git a/Documentation/devicetree/bindings/arm/psci.txt b/Documentation/devicetree/bindings/arm/psci.txt
new file mode 100644
index 0000000..433afe9
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/psci.txt
@@ -0,0 +1,55 @@
+* Power State Coordination Interface (PSCI)
+
+Firmware implementing the PSCI functions described in ARM document number
+ARM DEN 0022A ("Power State Coordination Interface System Software on ARM
+processors") can be used by Linux to initiate various CPU-centric power
+operations.
+
+Issue A of the specification describes functions for CPU suspend, hotplug
+and migration of secure software.
+
+Functions are invoked by trapping to the privilege level of the PSCI
+firmware (specified as part of the binding below) and passing arguments
+in a manner similar to that specified by AAPCS:
+
+	 r0		=> 32-bit Function ID / return value
+	{r1 - r3}	=> Parameters
+
+Note that the immediate field of the trapping instruction must be set
+to #0.
+
+
+Main node required properties:
+
+ - compatible    : Must be "arm,psci"
+
+ - method        : The method of calling the PSCI firmware. Permitted
+                   values are:
+
+                   "smc" : SMC #0, with the register assignments specified
+		           in this binding.
+
+                   "hvc" : HVC #0, with the register assignments specified
+		           in this binding.
+
+Main node optional properties:
+
+ - cpu_suspend   : Function ID for CPU_SUSPEND operation
+
+ - cpu_off       : Function ID for CPU_OFF operation
+
+ - cpu_on        : Function ID for CPU_ON operation
+
+ - migrate       : Function ID for MIGRATE operation
+
+
+Example:
+
+	psci {
+		compatible	= "arm,psci";
+		method		= "smc";
+		cpu_suspend	= <0x95c10000>;
+		cpu_off		= <0x95c10001>;
+		cpu_on		= <0x95c10002>;
+		migrate		= <0x95c10003>;
+	};
-- 
1.8.0

[PATCH v3 4/6] ARM: psci: add support for PSCI invocations from the kernel

[Will Deacon]

This patch adds support for the Power State Coordination Interface
defined by ARM, allowing Linux to request CPU-centric power-management
operations from firmware implementing the PSCI protocol.

Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
---
 arch/arm/Kconfig            |  10 +++
 arch/arm/include/asm/psci.h |  36 ++++++++
 arch/arm/kernel/Makefile    |   1 +
 arch/arm/kernel/psci.c      | 211 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 258 insertions(+)
 create mode 100644 arch/arm/include/asm/psci.h
 create mode 100644 arch/arm/kernel/psci.c

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8c83d98..80d54b8 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1617,6 +1617,16 @@ config HOTPLUG_CPU
 	  Say Y here to experiment with turning CPUs off and on.  CPUs
 	  can be controlled through /sys/devices/system/cpu.
 
+config ARM_PSCI
+	bool "Support for the ARM Power State Coordination Interface (PSCI)"
+	depends on CPU_V7
+	help
+	  Say Y here if you want Linux to communicate with system firmware
+	  implementing the PSCI specification for CPU-centric power
+	  management operations described in ARM document number ARM DEN
+	  0022A ("Power State Coordination Interface System Software on
+	  ARM processors").
+
 config LOCAL_TIMERS
 	bool "Use local timer interrupts"
 	depends on SMP
diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
new file mode 100644
index 0000000..ce0dbe7
--- /dev/null
+++ b/arch/arm/include/asm/psci.h
@@ -0,0 +1,36 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#ifndef __ASM_ARM_PSCI_H
+#define __ASM_ARM_PSCI_H
+
+#define PSCI_POWER_STATE_TYPE_STANDBY		0
+#define PSCI_POWER_STATE_TYPE_POWER_DOWN	1
+
+struct psci_power_state {
+	u16	id;
+	u8	type;
+	u8	affinity_level;
+};
+
+struct psci_operations {
+	int (*cpu_suspend)(struct psci_power_state state,
+			   unsigned long entry_point);
+	int (*cpu_off)(struct psci_power_state state);
+	int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
+	int (*migrate)(unsigned long cpuid);
+};
+
+extern struct psci_operations psci_ops;
+
+#endif /* __ASM_ARM_PSCI_H */
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 5bbec7b..5f3338e 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -82,5 +82,6 @@ obj-$(CONFIG_DEBUG_LL)	+= debug.o
 obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 
 obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
+obj-$(CONFIG_ARM_PSCI)		+= psci.o
 
 extra-y := $(head-y) vmlinux.lds
diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
new file mode 100644
index 0000000..3653164
--- /dev/null
+++ b/arch/arm/kernel/psci.c
@@ -0,0 +1,211 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
+ */
+
+#define pr_fmt(fmt) "psci: " fmt
+
+#include <linux/init.h>
+#include <linux/of.h>
+
+#include <asm/compiler.h>
+#include <asm/errno.h>
+#include <asm/opcodes-sec.h>
+#include <asm/opcodes-virt.h>
+#include <asm/psci.h>
+
+struct psci_operations psci_ops;
+
+static int (*invoke_psci_fn)(u32, u32, u32, u32);
+
+enum psci_function {
+	PSCI_FN_CPU_SUSPEND,
+	PSCI_FN_CPU_ON,
+	PSCI_FN_CPU_OFF,
+	PSCI_FN_MIGRATE,
+	PSCI_FN_MAX,
+};
+
+static u32 psci_function_id[PSCI_FN_MAX];
+
+#define PSCI_RET_SUCCESS		0
+#define PSCI_RET_EOPNOTSUPP		-1
+#define PSCI_RET_EINVAL			-2
+#define PSCI_RET_EPERM			-3
+
+static int psci_to_linux_errno(int errno)
+{
+	switch (errno) {
+	case PSCI_RET_SUCCESS:
+		return 0;
+	case PSCI_RET_EOPNOTSUPP:
+		return -EOPNOTSUPP;
+	case PSCI_RET_EINVAL:
+		return -EINVAL;
+	case PSCI_RET_EPERM:
+		return -EPERM;
+	};
+
+	return -EINVAL;
+}
+
+#define PSCI_POWER_STATE_ID_MASK	0xffff
+#define PSCI_POWER_STATE_ID_SHIFT	0
+#define PSCI_POWER_STATE_TYPE_MASK	0x1
+#define PSCI_POWER_STATE_TYPE_SHIFT	16
+#define PSCI_POWER_STATE_AFFL_MASK	0x3
+#define PSCI_POWER_STATE_AFFL_SHIFT	24
+
+static u32 psci_power_state_pack(struct psci_power_state state)
+{
+	return	((state.id & PSCI_POWER_STATE_ID_MASK)
+			<< PSCI_POWER_STATE_ID_SHIFT)	|
+		((state.type & PSCI_POWER_STATE_TYPE_MASK)
+			<< PSCI_POWER_STATE_TYPE_SHIFT)	|
+		((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK)
+			<< PSCI_POWER_STATE_AFFL_SHIFT);
+}
+
+/*
+ * The following two functions are invoked via the invoke_psci_fn pointer
+ * and will not be inlined, allowing us to piggyback on the AAPCS.
+ */
+static noinline int __invoke_psci_fn_hvc(u32 function_id, u32 arg0, u32 arg1,
+					 u32 arg2)
+{
+	asm volatile(
+			__asmeq("%0", "r0")
+			__asmeq("%1", "r1")
+			__asmeq("%2", "r2")
+			__asmeq("%3", "r3")
+			__HVC(0)
+		: "+r" (function_id)
+		: "r" (arg0), "r" (arg1), "r" (arg2));
+
+	return function_id;
+}
+
+static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
+					 u32 arg2)
+{
+	asm volatile(
+			__asmeq("%0", "r0")
+			__asmeq("%1", "r1")
+			__asmeq("%2", "r2")
+			__asmeq("%3", "r3")
+			__SMC(0)
+		: "+r" (function_id)
+		: "r" (arg0), "r" (arg1), "r" (arg2));
+
+	return function_id;
+}
+
+static int psci_cpu_suspend(struct psci_power_state state,
+			    unsigned long entry_point)
+{
+	int err;
+	u32 fn, power_state;
+
+	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
+	power_state = psci_power_state_pack(state);
+	err = invoke_psci_fn(fn, power_state, entry_point, 0);
+	return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_off(struct psci_power_state state)
+{
+	int err;
+	u32 fn, power_state;
+
+	fn = psci_function_id[PSCI_FN_CPU_OFF];
+	power_state = psci_power_state_pack(state);
+	err = invoke_psci_fn(fn, power_state, 0, 0);
+	return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
+{
+	int err;
+	u32 fn;
+
+	fn = psci_function_id[PSCI_FN_CPU_ON];
+	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
+	return psci_to_linux_errno(err);
+}
+
+static int psci_migrate(unsigned long cpuid)
+{
+	int err;
+	u32 fn;
+
+	fn = psci_function_id[PSCI_FN_MIGRATE];
+	err = invoke_psci_fn(fn, cpuid, 0, 0);
+	return psci_to_linux_errno(err);
+}
+
+static const struct of_device_id psci_of_match[] __initconst = {
+	{ .compatible = "arm,psci",	},
+	{},
+};
+
+static int __init psci_init(void)
+{
+	struct device_node *np;
+	const char *method;
+	u32 id;
+
+	np = of_find_matching_node(NULL, psci_of_match);
+	if (!np)
+		return 0;
+
+	pr_info("probing function IDs from device-tree\n");
+
+	if (of_property_read_string(np, "method", &method)) {
+		pr_warning("missing \"method\" property\n");
+		goto out_put_node;
+	}
+
+	if (!strcmp("hvc", method)) {
+		invoke_psci_fn = __invoke_psci_fn_hvc;
+	} else if (!strcmp("smc", method)) {
+		invoke_psci_fn = __invoke_psci_fn_smc;
+	} else {
+		pr_warning("invalid \"method\" property: %s\n", method);
+		goto out_put_node;
+	}
+
+	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
+		psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
+		psci_ops.cpu_suspend = psci_cpu_suspend;
+	}
+
+	if (!of_property_read_u32(np, "cpu_off", &id)) {
+		psci_function_id[PSCI_FN_CPU_OFF] = id;
+		psci_ops.cpu_off = psci_cpu_off;
+	}
+
+	if (!of_property_read_u32(np, "cpu_on", &id)) {
+		psci_function_id[PSCI_FN_CPU_ON] = id;
+		psci_ops.cpu_on = psci_cpu_on;
+	}
+
+	if (!of_property_read_u32(np, "migrate", &id)) {
+		psci_function_id[PSCI_FN_MIGRATE] = id;
+		psci_ops.migrate = psci_migrate;
+	}
+
+out_put_node:
+	of_node_put(np);
+	return 0;
+}
+early_initcall(psci_init);
-- 
1.8.0

[PATCH v3 5/6] ARM: Dummy Virtual Machine platform support

[Will Deacon]

From: Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>

Add support for the smallest, dumbest possible platform, to be
used as a guest for KVM or other hypervisors.

It only mandates a GIC and architected timers. Fits nicely with
a multiplatform zImage. Uses very little silicon area.

Signed-off-by: Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
---
 arch/arm/Kconfig            |  2 ++
 arch/arm/Makefile           |  1 +
 arch/arm/mach-virt/Kconfig  |  9 +++++++
 arch/arm/mach-virt/Makefile |  5 ++++
 arch/arm/mach-virt/virt.c   | 65 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 82 insertions(+)
 create mode 100644 arch/arm/mach-virt/Kconfig
 create mode 100644 arch/arm/mach-virt/Makefile
 create mode 100644 arch/arm/mach-virt/virt.c

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 80d54b8..3443d89 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1130,6 +1130,8 @@ source "arch/arm/mach-versatile/Kconfig"
 source "arch/arm/mach-vexpress/Kconfig"
 source "arch/arm/plat-versatile/Kconfig"
 
+source "arch/arm/mach-virt/Kconfig"
+
 source "arch/arm/mach-vt8500/Kconfig"
 
 source "arch/arm/mach-w90x900/Kconfig"
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 30c443c..ea4f481 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -194,6 +194,7 @@ machine-$(CONFIG_ARCH_SOCFPGA)		+= socfpga
 machine-$(CONFIG_ARCH_SPEAR13XX)	+= spear13xx
 machine-$(CONFIG_ARCH_SPEAR3XX)		+= spear3xx
 machine-$(CONFIG_MACH_SPEAR600)		+= spear6xx
+machine-$(CONFIG_ARCH_VIRT)		+= virt
 machine-$(CONFIG_ARCH_ZYNQ)		+= zynq
 machine-$(CONFIG_ARCH_SUNXI)		+= sunxi
 
diff --git a/arch/arm/mach-virt/Kconfig b/arch/arm/mach-virt/Kconfig
new file mode 100644
index 0000000..a568a2a
--- /dev/null
+++ b/arch/arm/mach-virt/Kconfig
@@ -0,0 +1,9 @@
+config ARCH_VIRT
+	bool "Dummy Virtual Machine" if ARCH_MULTI_V7
+	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select ARM_GIC
+	select ARM_ARCH_TIMER
+	select HAVE_SMP
+	select CPU_V7
+	select SPARSE_IRQ
+	select USE_OF
diff --git a/arch/arm/mach-virt/Makefile b/arch/arm/mach-virt/Makefile
new file mode 100644
index 0000000..7ddbfa6
--- /dev/null
+++ b/arch/arm/mach-virt/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the linux kernel.
+#
+
+obj-y					:= virt.o
diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
new file mode 100644
index 0000000..174b9da
--- /dev/null
+++ b/arch/arm/mach-virt/virt.c
@@ -0,0 +1,65 @@
+/*
+ * Dummy Virtual Machine - does what it says on the tin.
+ *
+ * Copyright (C) 2012 ARM Ltd
+ * Authors: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>,
+ *          Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+
+#include <asm/arch_timer.h>
+#include <asm/hardware/gic.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/time.h>
+
+const static struct of_device_id irq_match[] = {
+	{ .compatible = "arm,cortex-a15-gic", .data = gic_of_init, },
+	{}
+};
+
+static void __init gic_init_irq(void)
+{
+	of_irq_init(irq_match);
+}
+
+static void __init virt_init(void)
+{
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+}
+
+static void __init virt_timer_init(void)
+{
+	WARN_ON(arch_timer_of_register() != 0);
+	WARN_ON(arch_timer_sched_clock_init() != 0);
+}
+
+static const char *virt_dt_match[] = {
+	"linux,dummy-virt",
+	NULL
+};
+
+static struct sys_timer virt_timer = {
+	.init = virt_timer_init,
+};
+
+DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
+	.init_irq	= gic_init_irq,
+	.handle_irq     = gic_handle_irq,
+	.timer		= &virt_timer,
+	.init_machine	= virt_init,
+	.dt_compat	= virt_dt_match,
+MACHINE_END
-- 
1.8.0

[PATCH v3 6/6] ARM: mach-virt: add SMP support using PSCI

[Will Deacon]

This patch adds support for SMP to mach-virt using the PSCI
infrastructure.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 arch/arm/mach-virt/Kconfig   |  1 +
 arch/arm/mach-virt/Makefile  |  1 +
 arch/arm/mach-virt/platsmp.c | 58 ++++++++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-virt/virt.c    |  4 +++
 4 files changed, 64 insertions(+)
 create mode 100644 arch/arm/mach-virt/platsmp.c

diff --git a/arch/arm/mach-virt/Kconfig b/arch/arm/mach-virt/Kconfig
index a568a2a..8958f0d 100644
--- a/arch/arm/mach-virt/Kconfig
+++ b/arch/arm/mach-virt/Kconfig
@@ -3,6 +3,7 @@ config ARCH_VIRT
 	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select ARM_GIC
 	select ARM_ARCH_TIMER
+	select ARM_PSCI
 	select HAVE_SMP
 	select CPU_V7
 	select SPARSE_IRQ
diff --git a/arch/arm/mach-virt/Makefile b/arch/arm/mach-virt/Makefile
index 7ddbfa6..042afc1 100644
--- a/arch/arm/mach-virt/Makefile
+++ b/arch/arm/mach-virt/Makefile
@@ -3,3 +3,4 @@
 #
 
 obj-y					:= virt.o
+obj-$(CONFIG_SMP)			+= platsmp.o
diff --git a/arch/arm/mach-virt/platsmp.c b/arch/arm/mach-virt/platsmp.c
new file mode 100644
index 0000000..e358beb
--- /dev/null
+++ b/arch/arm/mach-virt/platsmp.c
@@ -0,0 +1,58 @@
+/*
+ * Dummy Virtual Machine - does what it says on the tin.
+ *
+ * Copyright (C) 2012 ARM Ltd
+ * Author: Will Deacon <will.deacon@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/of.h>
+
+#include <asm/psci.h>
+#include <asm/smp_plat.h>
+#include <asm/hardware/gic.h>
+
+extern void secondary_startup(void);
+
+static void __init virt_smp_init_cpus(void)
+{
+	set_smp_cross_call(gic_raise_softirq);
+}
+
+static void __init virt_smp_prepare_cpus(unsigned int max_cpus)
+{
+}
+
+static int __cpuinit virt_boot_secondary(unsigned int cpu,
+					 struct task_struct *idle)
+{
+	if (psci_ops.cpu_on)
+		return psci_ops.cpu_on(cpu_logical_map(cpu),
+				       __pa(secondary_startup));
+	return -ENODEV;
+}
+
+static void __cpuinit virt_secondary_init(unsigned int cpu)
+{
+	gic_secondary_init(0);
+}
+
+struct smp_operations __initdata virt_smp_ops = {
+	.smp_init_cpus		= virt_smp_init_cpus,
+	.smp_prepare_cpus	= virt_smp_prepare_cpus,
+	.smp_secondary_init	= virt_secondary_init,
+	.smp_boot_secondary	= virt_boot_secondary,
+};
diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
index 174b9da..1d0a85a 100644
--- a/arch/arm/mach-virt/virt.c
+++ b/arch/arm/mach-virt/virt.c
@@ -20,6 +20,7 @@
 
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/smp.h>
 
 #include <asm/arch_timer.h>
 #include <asm/hardware/gic.h>
@@ -56,10 +57,13 @@ static struct sys_timer virt_timer = {
 	.init = virt_timer_init,
 };
 
+extern struct smp_operations virt_smp_ops;
+
 DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
 	.init_irq	= gic_init_irq,
 	.handle_irq     = gic_handle_irq,
 	.timer		= &virt_timer,
 	.init_machine	= virt_init,
+	.smp		= smp_ops(virt_smp_ops),
 	.dt_compat	= virt_dt_match,
 MACHINE_END
-- 
1.8.0

Re: [PATCH v3 0/6] Add support for a fake, para-virtualised machine

[Arnd Bergmann]

On Tuesday 18 December 2012, Will Deacon wrote:
> This is version three of the patches originally posted here:
> 
>   v1.) http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/135870.html
>   v2.) http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/137750.html
> 
> Thanks to all those who have provided comments so far.
> Changes for v3 include:
> 
>         * Ripped out *even more* SMP code by rebasing onto latest
>           mainline
>         * Removed function-base property from device-tree binding
>         * Annotated the low-level firmware invocation functions with
>           noinline to clarify intent
>         * Minor cleanups
> 
> As usual, testing this relies on KVM support for PSCI, a magic kvmtool
> and Mark Rutland's arch-timer patches.
> 

Acked-by: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>

Re: [PATCH v3 6/6] ARM: mach-virt: add SMP support using PSCI

[Nicolas Pitre]

On Tue, 18 Dec 2012, Will Deacon wrote:

> This patch adds support for SMP to mach-virt using the PSCI
> infrastructure.
> 
> Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>

Reviewed-by: Nicolas Pitre <nico-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>


> ---
>  arch/arm/mach-virt/Kconfig   |  1 +
>  arch/arm/mach-virt/Makefile  |  1 +
>  arch/arm/mach-virt/platsmp.c | 58 ++++++++++++++++++++++++++++++++++++++++++++
>  arch/arm/mach-virt/virt.c    |  4 +++
>  4 files changed, 64 insertions(+)
>  create mode 100644 arch/arm/mach-virt/platsmp.c
> 
> diff --git a/arch/arm/mach-virt/Kconfig b/arch/arm/mach-virt/Kconfig
> index a568a2a..8958f0d 100644
> --- a/arch/arm/mach-virt/Kconfig
> +++ b/arch/arm/mach-virt/Kconfig
> @@ -3,6 +3,7 @@ config ARCH_VIRT
>  	select ARCH_WANT_OPTIONAL_GPIOLIB
>  	select ARM_GIC
>  	select ARM_ARCH_TIMER
> +	select ARM_PSCI
>  	select HAVE_SMP
>  	select CPU_V7
>  	select SPARSE_IRQ
> diff --git a/arch/arm/mach-virt/Makefile b/arch/arm/mach-virt/Makefile
> index 7ddbfa6..042afc1 100644
> --- a/arch/arm/mach-virt/Makefile
> +++ b/arch/arm/mach-virt/Makefile
> @@ -3,3 +3,4 @@
>  #
>  
>  obj-y					:= virt.o
> +obj-$(CONFIG_SMP)			+= platsmp.o
> diff --git a/arch/arm/mach-virt/platsmp.c b/arch/arm/mach-virt/platsmp.c
> new file mode 100644
> index 0000000..e358beb
> --- /dev/null
> +++ b/arch/arm/mach-virt/platsmp.c
> @@ -0,0 +1,58 @@
> +/*
> + * Dummy Virtual Machine - does what it says on the tin.
> + *
> + * Copyright (C) 2012 ARM Ltd
> + * Author: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/smp.h>
> +#include <linux/of.h>
> +
> +#include <asm/psci.h>
> +#include <asm/smp_plat.h>
> +#include <asm/hardware/gic.h>
> +
> +extern void secondary_startup(void);
> +
> +static void __init virt_smp_init_cpus(void)
> +{
> +	set_smp_cross_call(gic_raise_softirq);
> +}
> +
> +static void __init virt_smp_prepare_cpus(unsigned int max_cpus)
> +{
> +}
> +
> +static int __cpuinit virt_boot_secondary(unsigned int cpu,
> +					 struct task_struct *idle)
> +{
> +	if (psci_ops.cpu_on)
> +		return psci_ops.cpu_on(cpu_logical_map(cpu),
> +				       __pa(secondary_startup));
> +	return -ENODEV;
> +}
> +
> +static void __cpuinit virt_secondary_init(unsigned int cpu)
> +{
> +	gic_secondary_init(0);
> +}
> +
> +struct smp_operations __initdata virt_smp_ops = {
> +	.smp_init_cpus		= virt_smp_init_cpus,
> +	.smp_prepare_cpus	= virt_smp_prepare_cpus,
> +	.smp_secondary_init	= virt_secondary_init,
> +	.smp_boot_secondary	= virt_boot_secondary,
> +};
> diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
> index 174b9da..1d0a85a 100644
> --- a/arch/arm/mach-virt/virt.c
> +++ b/arch/arm/mach-virt/virt.c
> @@ -20,6 +20,7 @@
>  
>  #include <linux/of_irq.h>
>  #include <linux/of_platform.h>
> +#include <linux/smp.h>
>  
>  #include <asm/arch_timer.h>
>  #include <asm/hardware/gic.h>
> @@ -56,10 +57,13 @@ static struct sys_timer virt_timer = {
>  	.init = virt_timer_init,
>  };
>  
> +extern struct smp_operations virt_smp_ops;
> +
>  DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
>  	.init_irq	= gic_init_irq,
>  	.handle_irq     = gic_handle_irq,
>  	.timer		= &virt_timer,
>  	.init_machine	= virt_init,
> +	.smp		= smp_ops(virt_smp_ops),
>  	.dt_compat	= virt_dt_match,
>  MACHINE_END
> -- 
> 1.8.0
> 

Re: [PATCH v3 3/6] ARM: psci: add devicetree binding for describing PSCI firmware

[Nicolas Pitre]

On Tue, 18 Dec 2012, Will Deacon wrote:

> This patch adds a new devicetree binding for describing PSCI firmware
> to Linux.
> 
> Signed-off-by: Will Deacon <will.deacon@arm.com>

Acked-by: Nicolas Pitre <nico@linaro.org>


> ---
>  Documentation/devicetree/bindings/arm/psci.txt | 55 ++++++++++++++++++++++++++
>  1 file changed, 55 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/psci.txt
> 
> diff --git a/Documentation/devicetree/bindings/arm/psci.txt b/Documentation/devicetree/bindings/arm/psci.txt
> new file mode 100644
> index 0000000..433afe9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/psci.txt
> @@ -0,0 +1,55 @@
> +* Power State Coordination Interface (PSCI)
> +
> +Firmware implementing the PSCI functions described in ARM document number
> +ARM DEN 0022A ("Power State Coordination Interface System Software on ARM
> +processors") can be used by Linux to initiate various CPU-centric power
> +operations.
> +
> +Issue A of the specification describes functions for CPU suspend, hotplug
> +and migration of secure software.
> +
> +Functions are invoked by trapping to the privilege level of the PSCI
> +firmware (specified as part of the binding below) and passing arguments
> +in a manner similar to that specified by AAPCS:
> +
> +	 r0		=> 32-bit Function ID / return value
> +	{r1 - r3}	=> Parameters
> +
> +Note that the immediate field of the trapping instruction must be set
> +to #0.
> +
> +
> +Main node required properties:
> +
> + - compatible    : Must be "arm,psci"
> +
> + - method        : The method of calling the PSCI firmware. Permitted
> +                   values are:
> +
> +                   "smc" : SMC #0, with the register assignments specified
> +		           in this binding.
> +
> +                   "hvc" : HVC #0, with the register assignments specified
> +		           in this binding.
> +
> +Main node optional properties:
> +
> + - cpu_suspend   : Function ID for CPU_SUSPEND operation
> +
> + - cpu_off       : Function ID for CPU_OFF operation
> +
> + - cpu_on        : Function ID for CPU_ON operation
> +
> + - migrate       : Function ID for MIGRATE operation
> +
> +
> +Example:
> +
> +	psci {
> +		compatible	= "arm,psci";
> +		method		= "smc";
> +		cpu_suspend	= <0x95c10000>;
> +		cpu_off		= <0x95c10001>;
> +		cpu_on		= <0x95c10002>;
> +		migrate		= <0x95c10003>;
> +	};
> -- 
> 1.8.0
> 

Re: [PATCH v3 4/6] ARM: psci: add support for PSCI invocations from the kernel

[Nicolas Pitre]

On Tue, 18 Dec 2012, Will Deacon wrote:

> This patch adds support for the Power State Coordination Interface
> defined by ARM, allowing Linux to request CPU-centric power-management
> operations from firmware implementing the PSCI protocol.
> 
> Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>

Acked-by: Nicolas Pitre <nico-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>


> ---
>  arch/arm/Kconfig            |  10 +++
>  arch/arm/include/asm/psci.h |  36 ++++++++
>  arch/arm/kernel/Makefile    |   1 +
>  arch/arm/kernel/psci.c      | 211 ++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 258 insertions(+)
>  create mode 100644 arch/arm/include/asm/psci.h
>  create mode 100644 arch/arm/kernel/psci.c
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 8c83d98..80d54b8 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1617,6 +1617,16 @@ config HOTPLUG_CPU
>  	  Say Y here to experiment with turning CPUs off and on.  CPUs
>  	  can be controlled through /sys/devices/system/cpu.
>  
> +config ARM_PSCI
> +	bool "Support for the ARM Power State Coordination Interface (PSCI)"
> +	depends on CPU_V7
> +	help
> +	  Say Y here if you want Linux to communicate with system firmware
> +	  implementing the PSCI specification for CPU-centric power
> +	  management operations described in ARM document number ARM DEN
> +	  0022A ("Power State Coordination Interface System Software on
> +	  ARM processors").
> +
>  config LOCAL_TIMERS
>  	bool "Use local timer interrupts"
>  	depends on SMP
> diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
> new file mode 100644
> index 0000000..ce0dbe7
> --- /dev/null
> +++ b/arch/arm/include/asm/psci.h
> @@ -0,0 +1,36 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * Copyright (C) 2012 ARM Limited
> + */
> +
> +#ifndef __ASM_ARM_PSCI_H
> +#define __ASM_ARM_PSCI_H
> +
> +#define PSCI_POWER_STATE_TYPE_STANDBY		0
> +#define PSCI_POWER_STATE_TYPE_POWER_DOWN	1
> +
> +struct psci_power_state {
> +	u16	id;
> +	u8	type;
> +	u8	affinity_level;
> +};
> +
> +struct psci_operations {
> +	int (*cpu_suspend)(struct psci_power_state state,
> +			   unsigned long entry_point);
> +	int (*cpu_off)(struct psci_power_state state);
> +	int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
> +	int (*migrate)(unsigned long cpuid);
> +};
> +
> +extern struct psci_operations psci_ops;
> +
> +#endif /* __ASM_ARM_PSCI_H */
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index 5bbec7b..5f3338e 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -82,5 +82,6 @@ obj-$(CONFIG_DEBUG_LL)	+= debug.o
>  obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
>  
>  obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
> +obj-$(CONFIG_ARM_PSCI)		+= psci.o
>  
>  extra-y := $(head-y) vmlinux.lds
> diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
> new file mode 100644
> index 0000000..3653164
> --- /dev/null
> +++ b/arch/arm/kernel/psci.c
> @@ -0,0 +1,211 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * Copyright (C) 2012 ARM Limited
> + *
> + * Author: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> + */
> +
> +#define pr_fmt(fmt) "psci: " fmt
> +
> +#include <linux/init.h>
> +#include <linux/of.h>
> +
> +#include <asm/compiler.h>
> +#include <asm/errno.h>
> +#include <asm/opcodes-sec.h>
> +#include <asm/opcodes-virt.h>
> +#include <asm/psci.h>
> +
> +struct psci_operations psci_ops;
> +
> +static int (*invoke_psci_fn)(u32, u32, u32, u32);
> +
> +enum psci_function {
> +	PSCI_FN_CPU_SUSPEND,
> +	PSCI_FN_CPU_ON,
> +	PSCI_FN_CPU_OFF,
> +	PSCI_FN_MIGRATE,
> +	PSCI_FN_MAX,
> +};
> +
> +static u32 psci_function_id[PSCI_FN_MAX];
> +
> +#define PSCI_RET_SUCCESS		0
> +#define PSCI_RET_EOPNOTSUPP		-1
> +#define PSCI_RET_EINVAL			-2
> +#define PSCI_RET_EPERM			-3
> +
> +static int psci_to_linux_errno(int errno)
> +{
> +	switch (errno) {
> +	case PSCI_RET_SUCCESS:
> +		return 0;
> +	case PSCI_RET_EOPNOTSUPP:
> +		return -EOPNOTSUPP;
> +	case PSCI_RET_EINVAL:
> +		return -EINVAL;
> +	case PSCI_RET_EPERM:
> +		return -EPERM;
> +	};
> +
> +	return -EINVAL;
> +}
> +
> +#define PSCI_POWER_STATE_ID_MASK	0xffff
> +#define PSCI_POWER_STATE_ID_SHIFT	0
> +#define PSCI_POWER_STATE_TYPE_MASK	0x1
> +#define PSCI_POWER_STATE_TYPE_SHIFT	16
> +#define PSCI_POWER_STATE_AFFL_MASK	0x3
> +#define PSCI_POWER_STATE_AFFL_SHIFT	24
> +
> +static u32 psci_power_state_pack(struct psci_power_state state)
> +{
> +	return	((state.id & PSCI_POWER_STATE_ID_MASK)
> +			<< PSCI_POWER_STATE_ID_SHIFT)	|
> +		((state.type & PSCI_POWER_STATE_TYPE_MASK)
> +			<< PSCI_POWER_STATE_TYPE_SHIFT)	|
> +		((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK)
> +			<< PSCI_POWER_STATE_AFFL_SHIFT);
> +}
> +
> +/*
> + * The following two functions are invoked via the invoke_psci_fn pointer
> + * and will not be inlined, allowing us to piggyback on the AAPCS.
> + */
> +static noinline int __invoke_psci_fn_hvc(u32 function_id, u32 arg0, u32 arg1,
> +					 u32 arg2)
> +{
> +	asm volatile(
> +			__asmeq("%0", "r0")
> +			__asmeq("%1", "r1")
> +			__asmeq("%2", "r2")
> +			__asmeq("%3", "r3")
> +			__HVC(0)
> +		: "+r" (function_id)
> +		: "r" (arg0), "r" (arg1), "r" (arg2));
> +
> +	return function_id;
> +}
> +
> +static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
> +					 u32 arg2)
> +{
> +	asm volatile(
> +			__asmeq("%0", "r0")
> +			__asmeq("%1", "r1")
> +			__asmeq("%2", "r2")
> +			__asmeq("%3", "r3")
> +			__SMC(0)
> +		: "+r" (function_id)
> +		: "r" (arg0), "r" (arg1), "r" (arg2));
> +
> +	return function_id;
> +}
> +
> +static int psci_cpu_suspend(struct psci_power_state state,
> +			    unsigned long entry_point)
> +{
> +	int err;
> +	u32 fn, power_state;
> +
> +	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
> +	power_state = psci_power_state_pack(state);
> +	err = invoke_psci_fn(fn, power_state, entry_point, 0);
> +	return psci_to_linux_errno(err);
> +}
> +
> +static int psci_cpu_off(struct psci_power_state state)
> +{
> +	int err;
> +	u32 fn, power_state;
> +
> +	fn = psci_function_id[PSCI_FN_CPU_OFF];
> +	power_state = psci_power_state_pack(state);
> +	err = invoke_psci_fn(fn, power_state, 0, 0);
> +	return psci_to_linux_errno(err);
> +}
> +
> +static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
> +{
> +	int err;
> +	u32 fn;
> +
> +	fn = psci_function_id[PSCI_FN_CPU_ON];
> +	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
> +	return psci_to_linux_errno(err);
> +}
> +
> +static int psci_migrate(unsigned long cpuid)
> +{
> +	int err;
> +	u32 fn;
> +
> +	fn = psci_function_id[PSCI_FN_MIGRATE];
> +	err = invoke_psci_fn(fn, cpuid, 0, 0);
> +	return psci_to_linux_errno(err);
> +}
> +
> +static const struct of_device_id psci_of_match[] __initconst = {
> +	{ .compatible = "arm,psci",	},
> +	{},
> +};
> +
> +static int __init psci_init(void)
> +{
> +	struct device_node *np;
> +	const char *method;
> +	u32 id;
> +
> +	np = of_find_matching_node(NULL, psci_of_match);
> +	if (!np)
> +		return 0;
> +
> +	pr_info("probing function IDs from device-tree\n");
> +
> +	if (of_property_read_string(np, "method", &method)) {
> +		pr_warning("missing \"method\" property\n");
> +		goto out_put_node;
> +	}
> +
> +	if (!strcmp("hvc", method)) {
> +		invoke_psci_fn = __invoke_psci_fn_hvc;
> +	} else if (!strcmp("smc", method)) {
> +		invoke_psci_fn = __invoke_psci_fn_smc;
> +	} else {
> +		pr_warning("invalid \"method\" property: %s\n", method);
> +		goto out_put_node;
> +	}
> +
> +	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
> +		psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
> +		psci_ops.cpu_suspend = psci_cpu_suspend;
> +	}
> +
> +	if (!of_property_read_u32(np, "cpu_off", &id)) {
> +		psci_function_id[PSCI_FN_CPU_OFF] = id;
> +		psci_ops.cpu_off = psci_cpu_off;
> +	}
> +
> +	if (!of_property_read_u32(np, "cpu_on", &id)) {
> +		psci_function_id[PSCI_FN_CPU_ON] = id;
> +		psci_ops.cpu_on = psci_cpu_on;
> +	}
> +
> +	if (!of_property_read_u32(np, "migrate", &id)) {
> +		psci_function_id[PSCI_FN_MIGRATE] = id;
> +		psci_ops.migrate = psci_migrate;
> +	}
> +
> +out_put_node:
> +	of_node_put(np);
> +	return 0;
> +}
> +early_initcall(psci_init);
> -- 
> 1.8.0
> 

Re: [PATCH v3 5/6] ARM: Dummy Virtual Machine platform support

[Nicolas Pitre]

On Tue, 18 Dec 2012, Will Deacon wrote:

> From: Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
> 
> Add support for the smallest, dumbest possible platform, to be
> used as a guest for KVM or other hypervisors.
> 
> It only mandates a GIC and architected timers. Fits nicely with
> a multiplatform zImage. Uses very little silicon area.
> 
> Signed-off-by: Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
> Signed-off-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>

Acked-by: Nicolas Pitre <nico-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>


> ---
>  arch/arm/Kconfig            |  2 ++
>  arch/arm/Makefile           |  1 +
>  arch/arm/mach-virt/Kconfig  |  9 +++++++
>  arch/arm/mach-virt/Makefile |  5 ++++
>  arch/arm/mach-virt/virt.c   | 65 +++++++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 82 insertions(+)
>  create mode 100644 arch/arm/mach-virt/Kconfig
>  create mode 100644 arch/arm/mach-virt/Makefile
>  create mode 100644 arch/arm/mach-virt/virt.c
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 80d54b8..3443d89 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1130,6 +1130,8 @@ source "arch/arm/mach-versatile/Kconfig"
>  source "arch/arm/mach-vexpress/Kconfig"
>  source "arch/arm/plat-versatile/Kconfig"
>  
> +source "arch/arm/mach-virt/Kconfig"
> +
>  source "arch/arm/mach-vt8500/Kconfig"
>  
>  source "arch/arm/mach-w90x900/Kconfig"
> diff --git a/arch/arm/Makefile b/arch/arm/Makefile
> index 30c443c..ea4f481 100644
> --- a/arch/arm/Makefile
> +++ b/arch/arm/Makefile
> @@ -194,6 +194,7 @@ machine-$(CONFIG_ARCH_SOCFPGA)		+= socfpga
>  machine-$(CONFIG_ARCH_SPEAR13XX)	+= spear13xx
>  machine-$(CONFIG_ARCH_SPEAR3XX)		+= spear3xx
>  machine-$(CONFIG_MACH_SPEAR600)		+= spear6xx
> +machine-$(CONFIG_ARCH_VIRT)		+= virt
>  machine-$(CONFIG_ARCH_ZYNQ)		+= zynq
>  machine-$(CONFIG_ARCH_SUNXI)		+= sunxi
>  
> diff --git a/arch/arm/mach-virt/Kconfig b/arch/arm/mach-virt/Kconfig
> new file mode 100644
> index 0000000..a568a2a
> --- /dev/null
> +++ b/arch/arm/mach-virt/Kconfig
> @@ -0,0 +1,9 @@
> +config ARCH_VIRT
> +	bool "Dummy Virtual Machine" if ARCH_MULTI_V7
> +	select ARCH_WANT_OPTIONAL_GPIOLIB
> +	select ARM_GIC
> +	select ARM_ARCH_TIMER
> +	select HAVE_SMP
> +	select CPU_V7
> +	select SPARSE_IRQ
> +	select USE_OF
> diff --git a/arch/arm/mach-virt/Makefile b/arch/arm/mach-virt/Makefile
> new file mode 100644
> index 0000000..7ddbfa6
> --- /dev/null
> +++ b/arch/arm/mach-virt/Makefile
> @@ -0,0 +1,5 @@
> +#
> +# Makefile for the linux kernel.
> +#
> +
> +obj-y					:= virt.o
> diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
> new file mode 100644
> index 0000000..174b9da
> --- /dev/null
> +++ b/arch/arm/mach-virt/virt.c
> @@ -0,0 +1,65 @@
> +/*
> + * Dummy Virtual Machine - does what it says on the tin.
> + *
> + * Copyright (C) 2012 ARM Ltd
> + * Authors: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>,
> + *          Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +
> +#include <asm/arch_timer.h>
> +#include <asm/hardware/gic.h>
> +#include <asm/mach/arch.h>
> +#include <asm/mach/time.h>
> +
> +const static struct of_device_id irq_match[] = {
> +	{ .compatible = "arm,cortex-a15-gic", .data = gic_of_init, },
> +	{}
> +};
> +
> +static void __init gic_init_irq(void)
> +{
> +	of_irq_init(irq_match);
> +}
> +
> +static void __init virt_init(void)
> +{
> +	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
> +}
> +
> +static void __init virt_timer_init(void)
> +{
> +	WARN_ON(arch_timer_of_register() != 0);
> +	WARN_ON(arch_timer_sched_clock_init() != 0);
> +}
> +
> +static const char *virt_dt_match[] = {
> +	"linux,dummy-virt",
> +	NULL
> +};
> +
> +static struct sys_timer virt_timer = {
> +	.init = virt_timer_init,
> +};
> +
> +DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
> +	.init_irq	= gic_init_irq,
> +	.handle_irq     = gic_handle_irq,
> +	.timer		= &virt_timer,
> +	.init_machine	= virt_init,
> +	.dt_compat	= virt_dt_match,
> +MACHINE_END
> -- 
> 1.8.0
>