[GIT PULL] cpuidle: A few improvements for ARM cpuidle via DT

[GIT PULL] cpuidle: A few improvements for ARM cpuidle via DT

[Daniel Lezcano]

Hi Rafael,

this pull request, based on 3.18-rc5, contains a set of changes from 
Lorenzo Pieralisi.

  * Added a 'status' definition flag in the DT to specify the 
unsupported firmware idle states and ignore those states in the parsing 
code when initializing the cpuidle driver

  * Added an idle state description in the DT. As the idle states are 
not standardized on ARM, the description gives information about the 
idle state

  * Removed duplicate error message in the arm64 cpuidle drivers

Thanks !

   -- Daniel


The following changes since commit fc14f9c1272f62c3e8d01300f52467c0d9af50f9:

   Linux 3.18-rc5 (2014-11-16 16:36:20 -0800)

are available in the git repository at:

   http://git.linaro.org/git-ro/people/daniel.lezcano/linux.git cpuidle/3.19

for you to fetch changes up to 18f95a3640dbf421ab9532e517070a0c1cd4d582:

   drivers: cpuidle: Remove cpuidle-arm64 duplicate error messages 
(2014-11-19 10:16:28 +0100)

----------------------------------------------------------------
Lorenzo Pieralisi (3):
       drivers: cpuidle: Add status property to ARM idle states
       drivers: cpuidle: Add idle-state-name description to ARM idle states
       drivers: cpuidle: Remove cpuidle-arm64 duplicate error messages

  Documentation/devicetree/bindings/arm/idle-states.txt | 20 
++++++++++++++++++++
  drivers/cpuidle/cpuidle-arm64.c                       | 13 ++-----------
  drivers/cpuidle/dt_idle_states.c                      | 10 +++++++++-
  3 files changed, 31 insertions(+), 12 deletions(-)

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[PATCH 1/3] drivers: cpuidle: Add status property to ARM idle states

[Daniel Lezcano]

From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

On some platforms the device tree bindings must provide the kernel
with a status flag for idle states, that defines whether the idle
state is operational or not in the current configuration.

This patch adds a status property to the ARM idle states compliant
with ePAPR v1.1 and updates the DT parsing code accordingly.

Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 Documentation/devicetree/bindings/arm/idle-states.txt | 14 ++++++++++++++
 drivers/cpuidle/dt_idle_states.c                      |  3 +++
 2 files changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/idle-states.txt b/Documentation/devicetree/bindings/arm/idle-states.txt
index 37375c7..5e51511 100644
--- a/Documentation/devicetree/bindings/arm/idle-states.txt
+++ b/Documentation/devicetree/bindings/arm/idle-states.txt
@@ -317,6 +317,20 @@ follows:
 			    In such systems entry-latency-us + exit-latency-us
 			    will exceed wakeup-latency-us by this duration.
 
+	- status:
+		Usage: Optional
+		Value type: <string>
+		Definition: A standard device tree property [5] that indicates
+			    the operational status of an idle-state.
+			    If present, it shall be:
+			    "okay": to indicate that the idle state is
+				    operational.
+			    "disabled": to indicate that the idle state has
+					been disabled in firmware so it is not
+					operational.
+			    If the property is not present the idle-state must
+			    be considered operational.
+
 	In addition to the properties listed above, a state node may require
 	additional properties specifics to the entry-method defined in the
 	idle-states node, please refer to the entry-method bindings
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index 52f4d11..22840f4 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -169,6 +169,9 @@ int dt_init_idle_driver(struct cpuidle_driver *drv,
 		if (!state_node)
 			break;
 
+		if (!of_device_is_available(state_node))
+			continue;
+
 		if (!idle_state_valid(state_node, i, cpumask)) {
 			pr_warn("%s idle state not valid, bailing out\n",
 				state_node->full_name);
-- 
1.9.1

[PATCH 2/3] drivers: cpuidle: Add idle-state-name description to ARM idle states

[Daniel Lezcano]

From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

On ARM machines, where generally speaking the idle state numbering has
no fixed and standard meaning it is useful to provide a description
of the idle state inner workings for benchmarking and monitoring purposes.

This patch adds a property to the idle states bindings that if present
gives platform firmware a means of describing the idle state and export
the string description to user space.

The patch updates the DT parsing code accordingly to take the description,
if present, into consideration.

Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 Documentation/devicetree/bindings/arm/idle-states.txt | 6 ++++++
 drivers/cpuidle/dt_idle_states.c                      | 7 ++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/idle-states.txt b/Documentation/devicetree/bindings/arm/idle-states.txt
index 5e51511..a8274ea 100644
--- a/Documentation/devicetree/bindings/arm/idle-states.txt
+++ b/Documentation/devicetree/bindings/arm/idle-states.txt
@@ -331,6 +331,12 @@ follows:
 			    If the property is not present the idle-state must
 			    be considered operational.
 
+	- idle-state-name:
+		Usage: Optional
+		Value type: <string>
+		Definition: A string used as a descriptive name for the idle
+			    state.
+
 	In addition to the properties listed above, a state node may require
 	additional properties specifics to the entry-method defined in the
 	idle-states node, please refer to the entry-method bindings
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index 22840f4..5301912 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -27,6 +27,7 @@ static int init_state_node(struct cpuidle_state *idle_state,
 {
 	int err;
 	const struct of_device_id *match_id;
+	const char *desc;
 
 	match_id = of_match_node(matches, state_node);
 	if (!match_id)
@@ -73,6 +74,10 @@ static int init_state_node(struct cpuidle_state *idle_state,
 		return -EINVAL;
 	}
 
+	err = of_property_read_string(state_node, "idle-state-name", &desc);
+	if (err)
+		desc = state_node->name;
+
 	idle_state->flags = CPUIDLE_FLAG_TIME_VALID;
 	if (of_property_read_bool(state_node, "local-timer-stop"))
 		idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP;
@@ -82,7 +87,7 @@ static int init_state_node(struct cpuidle_state *idle_state,
 	 *	and desc become string pointers
 	 */
 	strncpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN - 1);
-	strncpy(idle_state->desc, state_node->name, CPUIDLE_DESC_LEN - 1);
+	strncpy(idle_state->desc, desc, CPUIDLE_DESC_LEN - 1);
 	return 0;
 }
 
-- 
1.9.1

[PATCH 3/3] drivers: cpuidle: Remove cpuidle-arm64 duplicate error messages

[Daniel Lezcano]

From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Current CPUidle driver for arm64 machines spits errors upon idle
state initialization and cpuidle driver registration failures.
These error messages are already printed in core code so there is
no need to print them again.

This patch removes the duplicate print messages from the cpuidle-arm64
driver.

Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/cpuidle/cpuidle-arm64.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/cpuidle/cpuidle-arm64.c b/drivers/cpuidle/cpuidle-arm64.c
index 50997ea..1b10f92e 100644
--- a/drivers/cpuidle/cpuidle-arm64.c
+++ b/drivers/cpuidle/cpuidle-arm64.c
@@ -104,11 +104,8 @@ static int __init arm64_idle_init(void)
 	 * reason to initialize the idle driver if only wfi is supported.
 	 */
 	ret = dt_init_idle_driver(drv, arm64_idle_state_match, 1);
-	if (ret <= 0) {
-		if (ret)
-			pr_err("failed to initialize idle states\n");
+	if (ret <= 0)
 		return ret ? : -ENODEV;
-	}
 
 	/*
 	 * Call arch CPU operations in order to initialize
@@ -122,12 +119,6 @@ static int __init arm64_idle_init(void)
 		}
 	}
 
-	ret = cpuidle_register(drv, NULL);
-	if (ret) {
-		pr_err("failed to register cpuidle driver\n");
-		return ret;
-	}
-
-	return 0;
+	return cpuidle_register(drv, NULL);
 }
 device_initcall(arm64_idle_init);
-- 
1.9.1

Re: [GIT PULL] cpuidle: A few improvements for ARM cpuidle via DT

[Rafael J. Wysocki]

On Wednesday, November 19, 2014 11:16:11 AM Daniel Lezcano wrote:
> 
> Hi Rafael,
> 
> this pull request, based on 3.18-rc5, contains a set of changes from 
> Lorenzo Pieralisi.
> 
>   * Added a 'status' definition flag in the DT to specify the 
> unsupported firmware idle states and ignore those states in the parsing 
> code when initializing the cpuidle driver
> 
>   * Added an idle state description in the DT. As the idle states are 
> not standardized on ARM, the description gives information about the 
> idle state
> 
>   * Removed duplicate error message in the arm64 cpuidle drivers
> 
> Thanks !
> 
>    -- Daniel
> 
> 
> The following changes since commit fc14f9c1272f62c3e8d01300f52467c0d9af50f9:
> 
>    Linux 3.18-rc5 (2014-11-16 16:36:20 -0800)
> 
> are available in the git repository at:
> 
>    http://git.linaro.org/git-ro/people/daniel.lezcano/linux.git cpuidle/3.19
> 
> for you to fetch changes up to 18f95a3640dbf421ab9532e517070a0c1cd4d582:
> 
>    drivers: cpuidle: Remove cpuidle-arm64 duplicate error messages 
> (2014-11-19 10:16:28 +0100)

Pulled, but I had a conflict with one patch from you I'd already queued up for
3.19-rc1.

Can you please have a look at my bleeding-edge branch and check if I resolved
the conflict correctly?

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [GIT PULL] cpuidle: A few improvements for ARM cpuidle via DT

[Daniel Lezcano]

On 11/21/2014 04:56 PM, Rafael J. Wysocki wrote:
> On Wednesday, November 19, 2014 11:16:11 AM Daniel Lezcano wrote:
>>
>> Hi Rafael,
>>
>> this pull request, based on 3.18-rc5, contains a set of changes from
>> Lorenzo Pieralisi.
>>
>>    * Added a 'status' definition flag in the DT to specify the
>> unsupported firmware idle states and ignore those states in the parsing
>> code when initializing the cpuidle driver
>>
>>    * Added an idle state description in the DT. As the idle states are
>> not standardized on ARM, the description gives information about the
>> idle state
>>
>>    * Removed duplicate error message in the arm64 cpuidle drivers
>>
>> Thanks !
>>
>>     -- Daniel
>>
>>
>> The following changes since commit fc14f9c1272f62c3e8d01300f52467c0d9af50f9:
>>
>>     Linux 3.18-rc5 (2014-11-16 16:36:20 -0800)
>>
>> are available in the git repository at:
>>
>>     http://git.linaro.org/git-ro/people/daniel.lezcano/linux.git cpuidle/3.19
>>
>> for you to fetch changes up to 18f95a3640dbf421ab9532e517070a0c1cd4d582:
>>
>>     drivers: cpuidle: Remove cpuidle-arm64 duplicate error messages
>> (2014-11-19 10:16:28 +0100)
>
> Pulled, but I had a conflict with one patch from you I'd already queued up for
> 3.19-rc1.
>
> Can you please have a look at my bleeding-edge branch and check if I resolved
> the conflict correctly?

Hi Rafael,

yes the conflict is correctly resolved.

Thanks
   -- Daniel



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