Re: [PATCH v6 08/12] arm64: dts: nuvoton: Add initial ma35d1 device tree

From: Stephen Boyd
Date: Tue Mar 28 2023 - 22:46:19 EST


Quoting Jacky Huang (2023-03-28 19:39:36)
> On 2023/3/29 上午 10:19, Stephen Boyd wrote:
> > What do you use the syscon for then? The clock driver must want to use
> > the syscon for something, implying that they are the same device.
>
> The register lock mechanism is applied to protect many critical
> registers from false written.
> The register lock control register is one register in system controller.
> Some registers of the clock controller are lock protected. Not only
> clock controller, but other
> IP such as RTC, PWM, ADC, etc, also have lock protected registers. All
> these IP requires
> syscon to access the lock/unlock control register in the system controller.
> That's why we add a <&sys> to the clock controller.
>
> Should we implement a ma35d1-sysctl driver to protect register_lock()
> and register_unlock()
> and export to those drivers?  If yes, we can remove the <&sys> from
> clock controller.
>

You can implement the lock and unlock in the hwspinlock framework. See
drivers/hwspinlock.