[PATCH v2 0/2] arm: kernel: implement cpuidle_ops with psci backend

[PATCH v2 0/2] arm: kernel: implement cpuidle_ops with psci backend

[Jisheng Zhang]

We'd like to use cpuidle-arm.c for both arm and arm64 with psci as backend.
For arm64, it works. But for arm, we miss cpuidle_ops, these patches try to
address this issue.

Has been tested on Marvell Berlin SoCs. These patches are rebased on the Mark
Rutland's latest psci unification work and Lorenzo Pieralisi's psci related
work[1].

[PATCH 1/2] move psci's cpu_suspend handling to generic code as suggested
	    by Lorenzo.
[PATCH 2/2] implement cpuidle_ops with psci finally.

Since v1:
 - add a new file psci_cpuidle.c to implment cpuidle_ops

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-May/347352.html

Jisheng Zhang (2):
  firmware: psci: move cpu_suspend handling to generic code
  arm: kernel: implement cpuidle_ops with psci backend

 arch/arm/kernel/Makefile       |  1 +
 arch/arm/kernel/psci_cpuidle.c | 29 +++++++++++++
 arch/arm64/kernel/psci.c       | 95 ------------------------------------------
 drivers/firmware/psci.c        | 95 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/psci.h           |  2 +
 5 files changed, 127 insertions(+), 95 deletions(-)
 create mode 100644 arch/arm/kernel/psci_cpuidle.c

-- 
2.1.4

[PATCH v2 1/2] firmware: psci: move cpu_suspend handling to generic code

[Jisheng Zhang]

Functions implemented on arm64 to suspend cpu and translate the idle
state index passed by the cpu_suspend core call to a valid PSCI state
are not arm64 specific and should be moved to generic code so that they
can be reused on arm systems too.

This patch moves these functions to generic PSCI firmware layer code.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
---
 arch/arm64/kernel/psci.c | 95 ------------------------------------------------
 drivers/firmware/psci.c  | 95 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/psci.h     |  2 +
 3 files changed, 97 insertions(+), 95 deletions(-)

diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index 4be5972..06e5c9a 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -20,7 +20,6 @@
 #include <linux/smp.h>
 #include <linux/delay.h>
 #include <linux/psci.h>
-#include <linux/slab.h>
 
 #include <uapi/linux/psci.h>
 
@@ -28,73 +27,6 @@
 #include <asm/cpu_ops.h>
 #include <asm/errno.h>
 #include <asm/smp_plat.h>
-#include <asm/suspend.h>
-
-static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
-
-static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu)
-{
-	int i, ret, count = 0;
-	u32 *psci_states;
-	struct device_node *state_node, *cpu_node;
-
-	cpu_node = of_get_cpu_node(cpu, NULL);
-	if (!cpu_node)
-		return -ENODEV;
-
-	/*
-	 * If the PSCI cpu_suspend function hook has not been initialized
-	 * idle states must not be enabled, so bail out
-	 */
-	if (!psci_ops.cpu_suspend)
-		return -EOPNOTSUPP;
-
-	/* Count idle states */
-	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
-					      count))) {
-		count++;
-		of_node_put(state_node);
-	}
-
-	if (!count)
-		return -ENODEV;
-
-	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
-	if (!psci_states)
-		return -ENOMEM;
-
-	for (i = 0; i < count; i++) {
-		u32 state;
-
-		state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
-
-		ret = of_property_read_u32(state_node,
-					   "arm,psci-suspend-param",
-					   &state);
-		if (ret) {
-			pr_warn(" * %s missing arm,psci-suspend-param property\n",
-				state_node->full_name);
-			of_node_put(state_node);
-			goto free_mem;
-		}
-
-		of_node_put(state_node);
-		pr_debug("psci-power-state %#x index %d\n", state, i);
-		if (!psci_power_state_is_valid(state)) {
-			pr_warn("Invalid PSCI power state %#x\n", state);
-			ret = -EINVAL;
-			goto free_mem;
-		}
-		psci_states[i] = state;
-	}
-	/* Idle states parsed correctly, initialize per-cpu pointer */
-	per_cpu(psci_power_state, cpu) = psci_states;
-	return 0;
-
-free_mem:
-	kfree(psci_states);
-	return ret;
-}
 
 #ifdef CONFIG_SMP
 
@@ -181,33 +113,6 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
 #endif
 #endif
 
-static int psci_suspend_finisher(unsigned long index)
-{
-	u32 *state = __this_cpu_read(psci_power_state);
-
-	return psci_ops.cpu_suspend(state[index - 1],
-				    virt_to_phys(cpu_resume));
-}
-
-static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
-{
-	int ret;
-	u32 *state = __this_cpu_read(psci_power_state);
-	/*
-	 * idle state index 0 corresponds to wfi, should never be called
-	 * from the cpu_suspend operations
-	 */
-	if (WARN_ON_ONCE(!index))
-		return -EINVAL;
-
-	if (!psci_power_state_loses_context(state[index - 1]))
-		ret = psci_ops.cpu_suspend(state[index - 1], 0);
-	else
-		ret = cpu_suspend(index, psci_suspend_finisher);
-
-	return ret;
-}
-
 const struct cpu_operations cpu_psci_ops = {
 	.name		= "psci",
 #ifdef CONFIG_CPU_IDLE
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
index 2f5d611..5da8aa2 100644
--- a/drivers/firmware/psci.c
+++ b/drivers/firmware/psci.c
@@ -20,12 +20,14 @@
 #include <linux/printk.h>
 #include <linux/psci.h>
 #include <linux/reboot.h>
+#include <linux/slab.h>
 
 #include <uapi/linux/psci.h>
 
 #include <asm/cputype.h>
 #include <asm/system_misc.h>
 #include <asm/smp_plat.h>
+#include <asm/suspend.h>
 
 /*
  * While a 64-bit OS can make calls with SMC32 calling conventions, for some
@@ -81,6 +83,8 @@ static u32 psci_function_id[PSCI_FN_MAX];
 
 static u32 psci_cpu_suspend_feature;
 
+static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
+
 static inline bool psci_has_ext_power_state(void)
 {
 	return psci_cpu_suspend_feature &
@@ -217,6 +221,97 @@ static void psci_sys_poweroff(void)
 	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
 }
 
+int cpu_psci_cpu_init_idle(unsigned int cpu)
+{
+	int i, ret, count = 0;
+	u32 *psci_states;
+	struct device_node *state_node, *cpu_node;
+
+	cpu_node = of_get_cpu_node(cpu, NULL);
+	if (!cpu_node)
+		return -ENODEV;
+
+	/*
+	 * If the PSCI cpu_suspend function hook has not been initialized
+	 * idle states must not be enabled, so bail out
+	 */
+	if (!psci_ops.cpu_suspend)
+		return -EOPNOTSUPP;
+
+	/* Count idle states */
+	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
+					      count))) {
+		count++;
+		of_node_put(state_node);
+	}
+
+	if (!count)
+		return -ENODEV;
+
+	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
+	if (!psci_states)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		u32 state;
+
+		state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
+
+		ret = of_property_read_u32(state_node,
+					   "arm,psci-suspend-param",
+					   &state);
+		if (ret) {
+			pr_warn(" * %s missing arm,psci-suspend-param property\n",
+				state_node->full_name);
+			of_node_put(state_node);
+			goto free_mem;
+		}
+
+		of_node_put(state_node);
+		pr_debug("psci-power-state %#x index %d\n", state, i);
+		if (!psci_power_state_is_valid(state)) {
+			pr_warn("Invalid PSCI power state %#x\n", state);
+			ret = -EINVAL;
+			goto free_mem;
+		}
+		psci_states[i] = state;
+	}
+	/* Idle states parsed correctly, initialize per-cpu pointer */
+	per_cpu(psci_power_state, cpu) = psci_states;
+	return 0;
+
+free_mem:
+	kfree(psci_states);
+	return ret;
+}
+
+static int psci_suspend_finisher(unsigned long index)
+{
+	u32 *state = __this_cpu_read(psci_power_state);
+
+	return psci_ops.cpu_suspend(state[index - 1],
+				    virt_to_phys(cpu_resume));
+}
+
+int cpu_psci_cpu_suspend(unsigned long index)
+{
+	int ret;
+	u32 *state = __this_cpu_read(psci_power_state);
+	/*
+	 * idle state index 0 corresponds to wfi, should never be called
+	 * from the cpu_suspend operations
+	 */
+	if (WARN_ON_ONCE(!index))
+		return -EINVAL;
+
+	if (!psci_power_state_loses_context(state[index - 1]))
+		ret = psci_ops.cpu_suspend(state[index - 1], 0);
+	else
+		ret = cpu_suspend(index, psci_suspend_finisher);
+
+	return ret;
+}
+
 static int __init psci_features(u32 psci_func_id)
 {
 	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
diff --git a/include/linux/psci.h b/include/linux/psci.h
index 12c4865..cbb49a3 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h
@@ -23,6 +23,8 @@
 bool psci_tos_resident_on(int cpu);
 bool psci_power_state_loses_context(u32 state);
 bool psci_power_state_is_valid(u32 state);
+int cpu_psci_cpu_init_idle(unsigned int cpu);
+int cpu_psci_cpu_suspend(unsigned long index);
 
 struct psci_operations {
 	int (*cpu_suspend)(u32 state, unsigned long entry_point);
-- 
2.1.4

[PATCH v2 2/2] arm: kernel: implement cpuidle_ops with psci backend

[Jisheng Zhang]

This patch implements cpuidle_ops using psci. After this patch, we can
use cpuidle-arm.c with psci backend for both arm and arm64.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
---
 arch/arm/kernel/Makefile       |  1 +
 arch/arm/kernel/psci_cpuidle.c | 29 +++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 arch/arm/kernel/psci_cpuidle.c

diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 3b995f5..96383d8 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
 ifeq ($(CONFIG_ARM_PSCI),y)
 obj-y				+= psci-call.o
 obj-$(CONFIG_SMP)		+= psci_smp.o
+obj-$(CONFIG_CPU_IDLE)		+= psci_cpuidle.o
 endif
 
 extra-y := $(head-y) vmlinux.lds
diff --git a/arch/arm/kernel/psci_cpuidle.c b/arch/arm/kernel/psci_cpuidle.c
new file mode 100644
index 0000000..ae85d97
--- /dev/null
+++ b/arch/arm/kernel/psci_cpuidle.c
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2015 Marvell Technology Group Ltd.
+ * Author: Jisheng Zhang <jszhang@marvell.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.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/psci.h>
+
+#include <asm/cpuidle.h>
+
+static int psci_cpuidle_suspend(int cpu, unsigned long arg)
+{
+	return cpu_psci_cpu_suspend(arg);
+}
+
+static int psci_cpuidle_init(struct device_node *node, int cpu)
+{
+	return cpu_psci_cpu_init_idle(cpu);
+}
+
+static struct cpuidle_ops psci_cpuidle_ops __initdata = {
+	.suspend = psci_cpuidle_suspend,
+	.init = psci_cpuidle_init,
+};
+CPUIDLE_METHOD_OF_DECLARE(psci_cpuidle, "psci", &psci_cpuidle_ops);
-- 
2.1.4

Re: [PATCH v2 1/2] firmware: psci: move cpu_suspend handling to generic code

[Lorenzo Pieralisi]

Hi Jisheng,

On Wed, Jul 08, 2015 at 01:51:07PM +0100, Jisheng Zhang wrote:
> Functions implemented on arm64 to suspend cpu and translate the idle
> state index passed by the cpu_suspend core call to a valid PSCI state
> are not arm64 specific and should be moved to generic code so that they
> can be reused on arm systems too.
> 
> This patch moves these functions to generic PSCI firmware layer code.
> 
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
>  arch/arm64/kernel/psci.c | 95 ------------------------------------------------
>  drivers/firmware/psci.c  | 95 ++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/psci.h     |  2 +
>  3 files changed, 97 insertions(+), 95 deletions(-)
>

Overall it seems fine, please rebase on top of the series I have
just posted (with a couple of change requests below):

http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/355098.html

> diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
> index 4be5972..06e5c9a 100644
> --- a/arch/arm64/kernel/psci.c
> +++ b/arch/arm64/kernel/psci.c
> @@ -20,7 +20,6 @@
>  #include <linux/smp.h>
>  #include <linux/delay.h>
>  #include <linux/psci.h>
> -#include <linux/slab.h>
>  
>  #include <uapi/linux/psci.h>
>  
> @@ -28,73 +27,6 @@
>  #include <asm/cpu_ops.h>
>  #include <asm/errno.h>
>  #include <asm/smp_plat.h>
> -#include <asm/suspend.h>
> -
> -static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
> -
> -static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu)
> -{
> -	int i, ret, count = 0;
> -	u32 *psci_states;
> -	struct device_node *state_node, *cpu_node;
> -
> -	cpu_node = of_get_cpu_node(cpu, NULL);
> -	if (!cpu_node)
> -		return -ENODEV;
> -
> -	/*
> -	 * If the PSCI cpu_suspend function hook has not been initialized
> -	 * idle states must not be enabled, so bail out
> -	 */
> -	if (!psci_ops.cpu_suspend)
> -		return -EOPNOTSUPP;
> -
> -	/* Count idle states */
> -	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
> -					      count))) {
> -		count++;
> -		of_node_put(state_node);
> -	}
> -
> -	if (!count)
> -		return -ENODEV;
> -
> -	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
> -	if (!psci_states)
> -		return -ENOMEM;
> -
> -	for (i = 0; i < count; i++) {
> -		u32 state;
> -
> -		state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
> -
> -		ret = of_property_read_u32(state_node,
> -					   "arm,psci-suspend-param",
> -					   &state);
> -		if (ret) {
> -			pr_warn(" * %s missing arm,psci-suspend-param property\n",
> -				state_node->full_name);
> -			of_node_put(state_node);
> -			goto free_mem;
> -		}
> -
> -		of_node_put(state_node);
> -		pr_debug("psci-power-state %#x index %d\n", state, i);
> -		if (!psci_power_state_is_valid(state)) {
> -			pr_warn("Invalid PSCI power state %#x\n", state);
> -			ret = -EINVAL;
> -			goto free_mem;
> -		}
> -		psci_states[i] = state;
> -	}
> -	/* Idle states parsed correctly, initialize per-cpu pointer */
> -	per_cpu(psci_power_state, cpu) = psci_states;
> -	return 0;
> -
> -free_mem:
> -	kfree(psci_states);
> -	return ret;
> -}
>  
>  #ifdef CONFIG_SMP
>  
> @@ -181,33 +113,6 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
>  #endif
>  #endif
>  
> -static int psci_suspend_finisher(unsigned long index)
> -{
> -	u32 *state = __this_cpu_read(psci_power_state);
> -
> -	return psci_ops.cpu_suspend(state[index - 1],
> -				    virt_to_phys(cpu_resume));
> -}
> -
> -static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
> -{
> -	int ret;
> -	u32 *state = __this_cpu_read(psci_power_state);
> -	/*
> -	 * idle state index 0 corresponds to wfi, should never be called
> -	 * from the cpu_suspend operations
> -	 */
> -	if (WARN_ON_ONCE(!index))
> -		return -EINVAL;
> -
> -	if (!psci_power_state_loses_context(state[index - 1]))
> -		ret = psci_ops.cpu_suspend(state[index - 1], 0);
> -	else
> -		ret = cpu_suspend(index, psci_suspend_finisher);
> -
> -	return ret;
> -}
> -
>  const struct cpu_operations cpu_psci_ops = {
>  	.name		= "psci",
>  #ifdef CONFIG_CPU_IDLE
> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
> index 2f5d611..5da8aa2 100644
> --- a/drivers/firmware/psci.c
> +++ b/drivers/firmware/psci.c
> @@ -20,12 +20,14 @@
>  #include <linux/printk.h>
>  #include <linux/psci.h>
>  #include <linux/reboot.h>
> +#include <linux/slab.h>
>  
>  #include <uapi/linux/psci.h>
>  
>  #include <asm/cputype.h>
>  #include <asm/system_misc.h>
>  #include <asm/smp_plat.h>
> +#include <asm/suspend.h>
>  
>  /*
>   * While a 64-bit OS can make calls with SMC32 calling conventions, for some
> @@ -81,6 +83,8 @@ static u32 psci_function_id[PSCI_FN_MAX];
>  
>  static u32 psci_cpu_suspend_feature;
>  
> +static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
> +
>  static inline bool psci_has_ext_power_state(void)
>  {
>  	return psci_cpu_suspend_feature &
> @@ -217,6 +221,97 @@ static void psci_sys_poweroff(void)
>  	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
>  }
>  
> +int cpu_psci_cpu_init_idle(unsigned int cpu)
> +{
> +	int i, ret, count = 0;
> +	u32 *psci_states;
> +	struct device_node *state_node, *cpu_node;
> +
> +	cpu_node = of_get_cpu_node(cpu, NULL);
> +	if (!cpu_node)
> +		return -ENODEV;
> +
> +	/*
> +	 * If the PSCI cpu_suspend function hook has not been initialized
> +	 * idle states must not be enabled, so bail out
> +	 */
> +	if (!psci_ops.cpu_suspend)
> +		return -EOPNOTSUPP;
> +
> +	/* Count idle states */
> +	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
> +					      count))) {
> +		count++;
> +		of_node_put(state_node);
> +	}
> +
> +	if (!count)
> +		return -ENODEV;
> +
> +	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
> +	if (!psci_states)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < count; i++) {
> +		u32 state;
> +
> +		state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
> +
> +		ret = of_property_read_u32(state_node,
> +					   "arm,psci-suspend-param",
> +					   &state);
> +		if (ret) {
> +			pr_warn(" * %s missing arm,psci-suspend-param property\n",
> +				state_node->full_name);
> +			of_node_put(state_node);
> +			goto free_mem;
> +		}
> +
> +		of_node_put(state_node);
> +		pr_debug("psci-power-state %#x index %d\n", state, i);
> +		if (!psci_power_state_is_valid(state)) {

psci_power_state_is_valid() can be made static and removed
from include/linux/psci.h

> +			pr_warn("Invalid PSCI power state %#x\n", state);
> +			ret = -EINVAL;
> +			goto free_mem;
> +		}
> +		psci_states[i] = state;
> +	}
> +	/* Idle states parsed correctly, initialize per-cpu pointer */
> +	per_cpu(psci_power_state, cpu) = psci_states;
> +	return 0;
> +
> +free_mem:
> +	kfree(psci_states);
> +	return ret;
> +}
> +
> +static int psci_suspend_finisher(unsigned long index)
> +{
> +	u32 *state = __this_cpu_read(psci_power_state);
> +
> +	return psci_ops.cpu_suspend(state[index - 1],
> +				    virt_to_phys(cpu_resume));
> +}
> +
> +int cpu_psci_cpu_suspend(unsigned long index)
> +{
> +	int ret;
> +	u32 *state = __this_cpu_read(psci_power_state);
> +	/*
> +	 * idle state index 0 corresponds to wfi, should never be called
> +	 * from the cpu_suspend operations
> +	 */
> +	if (WARN_ON_ONCE(!index))
> +		return -EINVAL;
> +
> +	if (!psci_power_state_loses_context(state[index - 1]))

psci_power_state_loses_context() can be made static and removed
from include/linux/psci.h

Thanks,
Lorenzo

> +		ret = psci_ops.cpu_suspend(state[index - 1], 0);
> +	else
> +		ret = cpu_suspend(index, psci_suspend_finisher);
> +
> +	return ret;
> +}
> +
>  static int __init psci_features(u32 psci_func_id)
>  {
>  	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
> diff --git a/include/linux/psci.h b/include/linux/psci.h
> index 12c4865..cbb49a3 100644
> --- a/include/linux/psci.h
> +++ b/include/linux/psci.h
> @@ -23,6 +23,8 @@
>  bool psci_tos_resident_on(int cpu);
>  bool psci_power_state_loses_context(u32 state);
>  bool psci_power_state_is_valid(u32 state);
> +int cpu_psci_cpu_init_idle(unsigned int cpu);
> +int cpu_psci_cpu_suspend(unsigned long index);

Re: [PATCH v2 2/2] arm: kernel: implement cpuidle_ops with psci backend

[Lorenzo Pieralisi]

On Wed, Jul 08, 2015 at 01:51:08PM +0100, Jisheng Zhang wrote:
> This patch implements cpuidle_ops using psci. After this patch, we can
> use cpuidle-arm.c with psci backend for both arm and arm64.
> 
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
>  arch/arm/kernel/Makefile       |  1 +
>  arch/arm/kernel/psci_cpuidle.c | 29 +++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+)
>  create mode 100644 arch/arm/kernel/psci_cpuidle.c
> 
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index 3b995f5..96383d8 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -91,6 +91,7 @@ obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
>  ifeq ($(CONFIG_ARM_PSCI),y)
>  obj-y				+= psci-call.o
>  obj-$(CONFIG_SMP)		+= psci_smp.o
> +obj-$(CONFIG_CPU_IDLE)		+= psci_cpuidle.o
>  endif
>  
>  extra-y := $(head-y) vmlinux.lds
> diff --git a/arch/arm/kernel/psci_cpuidle.c b/arch/arm/kernel/psci_cpuidle.c
> new file mode 100644
> index 0000000..ae85d97
> --- /dev/null
> +++ b/arch/arm/kernel/psci_cpuidle.c
> @@ -0,0 +1,29 @@
> +/*
> + * Copyright (C) 2015 Marvell Technology Group Ltd.
> + * Author: Jisheng Zhang <jszhang@marvell.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.
> + */
> +
> +#include <linux/cpuidle.h>
> +#include <linux/psci.h>
> +
> +#include <asm/cpuidle.h>
> +
> +static int psci_cpuidle_suspend(int cpu, unsigned long arg)
> +{
> +	return cpu_psci_cpu_suspend(arg);
> +}
> +
> +static int psci_cpuidle_init(struct device_node *node, int cpu)
> +{
> +	return cpu_psci_cpu_init_idle(cpu);
> +}

It probably makes sense to change the prototypes now that there is
just one cpuidle ops merged for arm, better now than later.

I am not too fussed about leaving these shims, but I think this can
save us some time in the future.

Daniel what do you think ?

Lorenzo

> +
> +static struct cpuidle_ops psci_cpuidle_ops __initdata = {
> +	.suspend = psci_cpuidle_suspend,
> +	.init = psci_cpuidle_init,
> +};
> +CPUIDLE_METHOD_OF_DECLARE(psci_cpuidle, "psci", &psci_cpuidle_ops);
> -- 
> 2.1.4
> 

Re: [PATCH v2 2/2] arm: kernel: implement cpuidle_ops with psci backend

[Jisheng Zhang]

Dear Lorenzo,

On Wed, 8 Jul 2015 18:34:58 +0100
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote:

> On Wed, Jul 08, 2015 at 01:51:08PM +0100, Jisheng Zhang wrote:
> > This patch implements cpuidle_ops using psci. After this patch, we can
> > use cpuidle-arm.c with psci backend for both arm and arm64.
> > 
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> > ---
> >  arch/arm/kernel/Makefile       |  1 +
> >  arch/arm/kernel/psci_cpuidle.c | 29 +++++++++++++++++++++++++++++
> >  2 files changed, 30 insertions(+)
> >  create mode 100644 arch/arm/kernel/psci_cpuidle.c
> > 
> > diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> > index 3b995f5..96383d8 100644
> > --- a/arch/arm/kernel/Makefile
> > +++ b/arch/arm/kernel/Makefile
> > @@ -91,6 +91,7 @@ obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
> >  ifeq ($(CONFIG_ARM_PSCI),y)
> >  obj-y				+= psci-call.o
> >  obj-$(CONFIG_SMP)		+= psci_smp.o
> > +obj-$(CONFIG_CPU_IDLE)		+= psci_cpuidle.o
> >  endif
> >  
> >  extra-y := $(head-y) vmlinux.lds
> > diff --git a/arch/arm/kernel/psci_cpuidle.c b/arch/arm/kernel/psci_cpuidle.c
> > new file mode 100644
> > index 0000000..ae85d97
> > --- /dev/null
> > +++ b/arch/arm/kernel/psci_cpuidle.c
> > @@ -0,0 +1,29 @@
> > +/*
> > + * Copyright (C) 2015 Marvell Technology Group Ltd.
> > + * Author: Jisheng Zhang <jszhang@marvell.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.
> > + */
> > +
> > +#include <linux/cpuidle.h>
> > +#include <linux/psci.h>
> > +
> > +#include <asm/cpuidle.h>
> > +
> > +static int psci_cpuidle_suspend(int cpu, unsigned long arg)
> > +{
> > +	return cpu_psci_cpu_suspend(arg);
> > +}
> > +
> > +static int psci_cpuidle_init(struct device_node *node, int cpu)
> > +{
> > +	return cpu_psci_cpu_init_idle(cpu);
> > +}
> 
> It probably makes sense to change the prototypes now that there is
> just one cpuidle ops merged for arm, better now than later.

Good idea. I will do as you suggested.

Thanks a lot,
Jisheng

> 
> I am not too fussed about leaving these shims, but I think this can
> save us some time in the future.
> 
> Daniel what do you think ?
> 
> Lorenzo
> 
> > +
> > +static struct cpuidle_ops psci_cpuidle_ops __initdata = {
> > +	.suspend = psci_cpuidle_suspend,
> > +	.init = psci_cpuidle_init,
> > +};
> > +CPUIDLE_METHOD_OF_DECLARE(psci_cpuidle, "psci", &psci_cpuidle_ops);
> > -- 
> > 2.1.4
> >