From mboxrd@z Thu Jan  1 00:00:00 1970
From: mark.rutland@arm.com (Mark Rutland)
Date: Mon, 29 Jul 2013 15:30:50 +0100
Subject: [PATCH 7/7] dts: calxeda: add ARM PSCI binding
In-Reply-To: <51F66A72.7070209@gmail.com>
References: <1375048598-15637-1-git-send-email-robherring2@gmail.com>
 <1375048598-15637-8-git-send-email-robherring2@gmail.com>
 <20130729102424.GA24255@e106331-lin.cambridge.arm.com>
 <51F66A72.7070209@gmail.com>
Message-ID: <20130729143050.GC25264@e106331-lin.cambridge.arm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, Jul 29, 2013 at 02:13:22PM +0100, Rob Herring wrote:
> On 07/29/2013 05:24 AM, Mark Rutland wrote:
> > On Sun, Jul 28, 2013 at 10:56:38PM +0100, Rob Herring wrote:
> >> From: Rob Herring <rob.herring@calxeda.com>
> >>
> >> Add the PSCI binding for Calxeda SOCs. The PSCI function numbers are
> >> different from the DT binding example because the numbering changed in
> >> revisions of the PSCI spec and are already fixed in highbank firmware.
> >> Since the numbering is transparent to the kernel, this difference is not
> >> significant.
> >>
> >> Signed-off-by: Rob Herring <rob.herring@calxeda.com>
> >> ---
> >>  arch/arm/boot/dts/ecx-common.dtsi | 10 ++++++++++
> >>  1 file changed, 10 insertions(+)
> >>
> >> diff --git a/arch/arm/boot/dts/ecx-common.dtsi b/arch/arm/boot/dts/ecx-common.dtsi
> >> index e8559b7..f1dfc09 100644
> >> --- a/arch/arm/boot/dts/ecx-common.dtsi
> >> +++ b/arch/arm/boot/dts/ecx-common.dtsi
> >> @@ -19,6 +19,16 @@
> >>  		bootargs = "console=ttyAMA0";
> >>  	};
> >>  
> >> +	psci {
> >> +		compatible	= "arm,psci";
> >> +		method		= "smc";
> >> +		cpu_suspend	= <0x84000002>;
> >> +		cpu_off		= <0x84000004>;
> >> +		cpu_on		= <0x84000006>;
> >> +		system_off	= <0x84000100>;
> >> +		system_reset	= <0x84000101>;
> >> +	};
> >> +
> > 
> > I see this is somewhat beyond the original PSCI, given the addition of
> > SYSTEM_OFF and SYSTEM_RESET, but not quite PSCI 0.2 as you don't have
> > PSCI_VERSION.
> 
> I do actually support PSCI_VERSION. Forgot to add that to the dts.

Ah, ok. Can you upgrade the compatible string to include "arm,psci-0.2"
while you're at it?

> 
> > It would be nice it the compatible string were more specific here to
> > deal with this and any implementation-specific power_state ID values.
> > Something like "calxeda,highbank-psci", "arm,psci" ?
> 
> Is that something we always want to do? You can't really know the
> implementation quirks up front.

While we might not know the quirks up front, it'll mean that when we
discover one we have a greater chance of being able to find out the
presence of the quirk from an old dts.

Thanks,
Mark.