Subject: [PATCHv2 8/8] ARM: dts: Add device tree sources for Exynos3250

From: [email-masked] (Marc Zyngier)
Date: Tue, 15 Apr 2014 10:24:39 +0100

On 15/04/14 10:19, Chanwoo Choi wrote:
> On 04/15/2014 06:13 PM, Marc Zyngier wrote:
>> On 15/04/14 09:27, Chanwoo Choi wrote:
>>> Hi,
>>>
>>> On 04/15/2014 05:15 PM, Marc Zyngier wrote:
>>>> On 15/04/14 02:59, Chanwoo Choi wrote:
>>>>> From: Tomasz Figa <[email-masked]>
>>>>>
>>>>> This patch add new exynos3250.dtsi to support Exynos3250 SoC based on Cortex-A7
>>>>> dual core and includes following dt nodes:
>>>>>
>>>>> - GIC interrupt controller
>>>>> - Pinctrl to control GPIOs
>>>>> - Clock controller
>>>>> - CPU information (Cortex-A7 dual core)
>>>>> - UART to support serial port
>>>>> - MCT (Multi Core Timer)
>>>>> - ADC (Analog Digital Converter)
>>>>> - I2C/SPI bus
>>>>> - Power domain
>>>>> - PMU (Performance Monitoring Unit)
>>>>> - MSHC (Mobile Storage Host Controller)
>>>>> - PWM (Pluse Width Modulation)
>>>>> - AMBA bus
>>>>
>>>> [...]
>>>>
>>>> Where is the arch timer node?
>>>
>>> Exynos3250 uses MCT (Multi Core Timer) instead of ARM_ARCH_TIMER.
>>> - in drivers/clocksource/exynos_mct.c
>>
>> Don't you have a Cortex-A7? If so, you have the arch timer.
> 
> Do you means that 'arch timer" is ARM_ARCH_TIMER?

Yes.

> As I knew, ARM_ARCH_TIMER is clocksource driver for system timer.
> But, Exynos SoC used MCT clocksource for system timer.
> 
> Exynos dts file didn't include arch timer node but only include mct node.

Well, it is a bug, and a recurrent one. A Cortex-A7 has the arch timers
implemented. Always.

http://infocenter.arm.com/help/topic/com.arm.doc.ddi0464f/BABFEBJJ.html

All Cortex-A7 have it, and so do A12, A15, A17, A53, A57.

Cheers,

	M.
-- 
Jazz is not dead. It just smells funny...