Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v2 1/9] arm64: dts: ti: k3-am65-main: Correct main NAVSS
 representation
To:     Lokesh Vutla <lokeshvutla@ti.com>, <t-kristo@ti.com>, <nm@ti.com>
CC:     <mark.rutland@arm.com>, <devicetree@vger.kernel.org>,
        <robh+dt@kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>
References: <20200122082621.4974-1-peter.ujfalusi@ti.com>
 <20200122082621.4974-2-peter.ujfalusi@ti.com>
 <600df214-620b-fa41-82ef-01132d9bdfae@ti.com>
From:   Peter Ujfalusi <peter.ujfalusi@ti.com>
Message-ID: <04a1bb97-f308-f866-ad4f-907cd7fb3515@ti.com>
Date:   Wed, 22 Jan 2020 13:39:48 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.9.0
MIME-Version: 1.0
In-Reply-To: <600df214-620b-fa41-82ef-01132d9bdfae@ti.com>
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


On 22/01/2020 13.03, Lokesh Vutla wrote:
> 
> 
> On 22/01/20 1:56 PM, Peter Ujfalusi wrote:
>> NAVSS is a subsystem containing different IPs, it is not really a bus.
>> Change the compatible from "simple-bus" to "simple-mfd" to reflect that.
>>
>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
>> ---
>>  arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
>> index efb24579922c..e40f7acbec42 100644
>> --- a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
>> +++ b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
>> @@ -385,8 +385,8 @@ intr_main_gpio: interrupt-controller0 {
>>  		ti,sci-rm-range-girq = <0x1>;
>>  	};
>>  
>> -	cbass_main_navss: interconnect0 {
>> -		compatible = "simple-bus";
>> +	cbass_main_navss: navss@30800000 {
> 
> This introduces below dtc warning when built with W=1
> 
> arch/arm64/boot/dts/ti/k3-am65-main.dtsi:388.35-530.4: Warning
> (unit_address_vs_reg): /interconnect@100000/navss@30800000: node has a unit
> name, but no reg property

Interesting, the example in
Documentation/devicetree/bindings/dma/ti/k3-udma.yaml

is basically the same and dt_binding_check is happy about it:
DTC     Documentation/devicetree/bindings/dma/ti/k3-udma.example.dt.yaml
CHECK   Documentation/devicetree/bindings/dma/ti/k3-udma.example.dt.yaml

but it screamed when I had the simple-bus in there (copied from the
existing dtsi file).

The node name for simple-bus _must_ be
'^(bus|soc|axi|ahb|apb)(@[0-9a-f]+)?$'

I would not use any of these to NAVSS node...

> this is representing cbass inside main_navss, just like cbass_main. You can drop
> this patch and the similar mcu version.

According to Documentation/devicetree/bindings/mfd/mfd.txt:
- compatible : "simple-mfd" - this signifies that the operating system
  should consider all subnodes of the MFD device as separate devices
  akin to how "simple-bus" indicates when to see subnodes as children
  for a simple memory-mapped bus.

NAVSS is falling into simple-mfd as the devices under it are independent
devices.

> 
> Thanks and regards,
> Lokesh
> 
>> +		compatible = "simple-mfd";
>>  		#address-cells = <2>;
>>  		#size-cells = <2>;
>>  		ranges;
>>

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki