[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[Keerthy]

Series enables CPU hotplug for K2HK. CPU Hotplug tested on
K2HK-EVM.

It is on top of 4.6-rc2.

Keerthy (2):
  keystone: dts: add psci command definition
  ARM: configs: keystone: Add CPU Hotplug related options

 arch/arm/boot/dts/keystone.dtsi     | 8 ++++++++
 arch/arm/configs/keystone_defconfig | 2 ++
 2 files changed, 10 insertions(+)

-- 
1.9.1

[PATCH 1/2] keystone: dts: add psci command definition

[Keerthy]

From: Vitaly Andrianov <vitalya@ti.com> 

This commit adds definition for cpu_on, cpu_off and cpu_suspend commands.
These definitions must match the corresponding PSCI definitions in
boot monitor.

Having those command and corresponding PSCI support in boot monitor allows
run time CPU hot plugin.

Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
---
 arch/arm/boot/dts/keystone.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/keystone.dtsi b/arch/arm/boot/dts/keystone.dtsi
index 3f27282..0076489 100644
--- a/arch/arm/boot/dts/keystone.dtsi
+++ b/arch/arm/boot/dts/keystone.dtsi
@@ -59,6 +59,14 @@
 			     <GIC_SPI 23 IRQ_TYPE_EDGE_RISING>;
 	};
 
+	psci {
+		compatible	= "arm,psci";
+		method		= "smc";
+		cpu_suspend	= <0x84000001>;
+		cpu_off		= <0x84000002>;
+		cpu_on		= <0x84000003>;
+	};
+
 	soc {
 		#address-cells = <1>;
 		#size-cells = <1>;
-- 
1.9.1

[PATCH 2/2] ARM: configs: keystone: Add CPU Hotplug related options

[Keerthy]

Add the config options needed to get CPU hotplug functional.

Signed-off-by: Keerthy <j-keerthy@ti.com>
---
 arch/arm/configs/keystone_defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/configs/keystone_defconfig b/arch/arm/configs/keystone_defconfig
index 5bcc9cf..faba04d 100644
--- a/arch/arm/configs/keystone_defconfig
+++ b/arch/arm/configs/keystone_defconfig
@@ -30,6 +30,8 @@ CONFIG_PCI=y
 CONFIG_PCI_MSI=y
 CONFIG_PCI_KEYSTONE=y
 CONFIG_SMP=y
+CONFIG_HOTPLUG_CPU=y
+CONFIG_ARM_PSCI=y
 CONFIG_PREEMPT=y
 CONFIG_AEABI=y
 CONFIG_HIGHMEM=y
-- 
1.9.1

[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[santosh shilimkar]

On 4/4/2016 11:29 AM, Keerthy wrote:
> Series enables CPU hotplug for K2HK. CPU Hotplug tested on
> K2HK-EVM.
>
> It is on top of 4.6-rc2.
>
> Keerthy (2):
>    keystone: dts: add psci command definition
>    ARM: configs: keystone: Add CPU Hotplug related options
>
Looks fine to me. Will add it to the 4.7 queue. Thanks !!

Reagrds,
Santosh

[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[Russell King - ARM Linux]

On Mon, Apr 04, 2016 at 07:13:51PM -0700, santosh shilimkar wrote:
> On 4/4/2016 11:29 AM, Keerthy wrote:
> >Series enables CPU hotplug for K2HK. CPU Hotplug tested on
> >K2HK-EVM.
> >
> >It is on top of 4.6-rc2.
> >
> >Keerthy (2):
> >   keystone: dts: add psci command definition
> >   ARM: configs: keystone: Add CPU Hotplug related options
> >
> Looks fine to me. Will add it to the 4.7 queue. Thanks !!

Just to note that this is required to get CPU hotplug working with
the TI keystone2 skern implementation, which is different to the
uboot psci code.

Now that I've been able to upgrade my board to a recent uboot and
skern, I can add this:

Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>

Now... if we could get the damn CPU fan under control, I might be
able to stand leaving the board powered on for longer, instead of
reaching for the power plug at the earliest possibility!

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[Russell King - ARM Linux]

On Tue, Apr 05, 2016 at 12:33:25PM +0100, Russell King - ARM Linux wrote:
> Now... if we could get the damn CPU fan under control, I might be
> able to stand leaving the board powered on for longer, instead of
> reaching for the power plug at the earliest possibility!

This evening, I've received a complaint about the noise of the fan,
which can be heard throughout the house.

PLEASE can we sort something out about this damned fan?  I know that
there's a PWM control of it, so let's get it more under control.  If
no one is interested in writing a driver for it, then please supply
me with the information so that I can sort this out, and stop it
being so annoying.

Like I've said above, right now the board doesn't stay on for very
long, and it's actually a very big _demotivator_ to powering the
board on.

This board is also *never* going anywhere near my boot farm because
it's just too damned noisy to be powered up during the night, even
if we do get the fan more under control once the kernel is running.

If that's not enough to get some help with this, I'll instead snip
the fan wire and solder a resistor in series with the fan to slow
the damned thing down to reduce the noise level.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

[PATCH 0/2] ARM: keystone: Enable CPU hotplug

[santosh shilimkar]

On 4/14/2016 3:15 PM, Russell King - ARM Linux wrote:
> On Tue, Apr 05, 2016 at 12:33:25PM +0100, Russell King - ARM Linux wrote:
>> Now... if we could get the damn CPU fan under control, I might be
>> able to stand leaving the board powered on for longer, instead of
>> reaching for the power plug at the earliest possibility!
>
> This evening, I've received a complaint about the noise of the fan,
> which can be heard throughout the house.
>
:-) Fan is noisy.

> PLEASE can we sort something out about this damned fan?  I know that
> there's a PWM control of it, so let's get it more under control.  If
> no one is interested in writing a driver for it, then please supply
> me with the information so that I can sort this out, and stop it
> being so annoying.
>
Am not sure if this fan is wired to PWM controller though.

> Like I've said above, right now the board doesn't stay on for very
> long, and it's actually a very big _demotivator_ to powering the
> board on.
>
> This board is also *never* going anywhere near my boot farm because
> it's just too damned noisy to be powered up during the night, even
> if we do get the fan more under control once the kernel is running.
>
> If that's not enough to get some help with this, I'll instead snip
> the fan wire and solder a resistor in series with the fan to slow
> the damned thing down to reduce the noise level.
>
You should do that. I have less hope of other options.


Regards,
Santosh