linux/Documentation/devicetree/bindings/arm/armada-cpu-reset.txt

Marvell Armada CPU reset controller
===================================

Required properties:

- compatible: Should be "marvell,armada-370-cpu-reset".

- reg: should be register base and length as documented in the
  datasheet for the CPU reset registers

cpurst: cpurst@20800 {
       compatible = "marvell,armada-370-cpu-reset";
       reg = <0x20800 0x20>;
};
ARM: mvebu: introduce CPU reset code The Armada 370 and Armada XP have registers that allow to reset the CPUs, which is particularly useful to take the secondary CPUs out of reset in the context of the SMP support. Unfortunately, an implementation mistake was originally made and the support for these registers was integrated into the PMSU driver, which is in fact completely unrelated. And it turns out that the Armada 375 has the same CPU reset registers, but does not have the PMSU registers. Therefore, this commit creates a small CPU reset driver. All it does is provide a simple mvebu_cpu_reset_deassert() function that the SMP support code can call to take secondary CPUs out of reset. As of this commit, the driver isn't being used, it will be used through changes in the following commits. Note that we initially planned to use the 'reset controller' framework, but it requires the addition of "resets" properties in the Device Tree, which are causing too many problems if we want to keep the Device Tree backward compatibility. Moreover, the 'reset controller' framework is mainly useful when a device driver needs to request a reset of its device from a separate reset controller. In our case, the CPU reset handling and the SMP core code are both located in arch/arm/mach-mvebu/ and are tightly linked together, so there's no real benefit in going through a separate framework. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Link: https://lkml.kernel.org/r/1397483433-25836-2-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper <jason@lakedaemon.net> 2014-04-14 13:50:28 +00:00			`Marvell Armada CPU reset controller`
			`===================================`

			`Required properties:`

			`- compatible: Should be "marvell,armada-370-cpu-reset".`

			`- reg: should be register base and length as documented in the`
			`datasheet for the CPU reset registers`

			`cpurst: cpurst@20800 {`
			`compatible = "marvell,armada-370-cpu-reset";`
			`reg = <0x20800 0x20>;`
			`};`