Re: [PATCH v6 3/3] ARM: dts: vf610: add Miscellaneous System Control Module (MSCM)
From: Stefan Agner
Date: Fri Mar 13 2015 - 05:42:31 EST
On 2015-03-13 05:48, Shawn Guo wrote:
> On Thu, Mar 12, 2015 at 10:03:08AM +0100, Stefan Agner wrote:
>> On 2015-03-11 01:48, Shawn Guo wrote:
>> > On Sun, Mar 01, 2015 at 11:41:29PM +0100, Stefan Agner wrote:
>> >> Add the Miscellaneous System Control Module (MSCM) to the base
>> >> device tree for Vybrid SoC's. This module contains registers
>> >> to get information of the individual and current (accessing)
>> >> CPU. In a second block, there is an interrupt router, which
>> >> handles the routing of the interrupts between the two CPU cores
>> >> on VF6xx variants of the SoC. However, also on single core
>> >> variants the interrupt router needs to be configured in order
>> >> to receive interrupts on the CPU's interrupt controller. Almost
>> >> all peripheral interrupts are routed through the router, hence
>> >> the MSCM module is the default interrupt parent for this SoC.
>> >> In a earlier commit the interrupt nodes were moved out of the
>> >> peripheral nodes and specified in the CPU specific vf500.dtsi
>> >> device tree. This allowed to use the base device tree vfxxx.dtsi
>> >> also for a Cortex-M4 specific device tree, which uses different
>> >> interrupt nodes due to the NVIC interrupt controller. However,
>> >> since the interrupt parent for peripherals is the MSCM module
>> >> independently which CPU the device tree is used for, we can move
>> >> the interrupt nodes into the base device tree vfxxx.dtsi again.
>> >> Depending on which CPU this base device tree will be used with,
>> >> the correct parent interrupt controller has to be assigned to
>> >> the MSCM-IR node (GIC or NVIC). The driver takes care of the
>> >> parent interrupt controller specific needs (interrupt-cells).
>> >> Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx>
>> >> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
>> > Stefan,
>> > I guess this patch has a run-time dependency on the first two in the
>> > series, right? Or put it another way, if I apply this single patch on
>> > my branch, the dtb and kernel built from the same branch do not work
>> > together, right? If so, we will need to either wait for the first two
>> > hit mainline or pull Jason's irqchip/vybrid branch into my tree as
>> > prerequisite (irqchip/vybrid needs to be stable).
>> > Shawn
>> Yes, that is true. The driver need to be in place in order to
>> successfully boot with the new device tree.
> Okay. Pulled Jason's irqchip/vybrid branch in, and applied the patch.
> There was a conflict on device dspi1 when applying the patch to my
> imx/dt branch. Please take a look to see if I solved it correctly.
Your updated patch looks good to me. Also quickly boot tested the
branch, worked fine.
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