ARM: keystone: Enable CPU hotplug

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

From: Vitaly Andrianov <[email protected]>

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.

---
 arch/arm/boot/dts/keystone.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

index 3f27282..0076489 100644
@@ -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

Add the config options needed to get CPU hotplug functional.

---
 arch/arm/configs/keystone_defconfig | 2 ++
 1 file changed, 2 insertions(+)

index 5bcc9cf..faba04d 100644
@@ -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

Looks fine to me. Will add it to the 4.7 queue. Thanks !!

Reagrds,
Santosh

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:

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.

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.

:-) Fan is noisy.

Am not sure if this fan is wired to PWM controller though.

You should do that. I have less hope of other options.

Regards,
Santosh