Re: [PATCH v3 1/4] dt-bindings: add SMP enable-method for Broadcom NSP

[Kapil Hali <kapilh@broadcom.com>]

Hi Rob,

On 11/7/2015 11:33 PM, Rob Herring wrote:
> On Fri, Nov 6, 2015 at 3:11 PM, Kapil Hali <kapilh@broadcom.com> wrote:
>> Add a compatible string "brcm,bcm-nsp-smp" for Broadcom's
>> Northstar Plus CPU to the 32-bit ARM CPU device tree binding
>> documentation file and create a new binding documentation for
>> Northstar Plus CPU.
>>
>> Signed-off-by: Kapil Hali <kapilh@broadcom.com>
>> ---
>>  .../bindings/arm/bcm/brcm,nsp-cpu-method.txt       | 36 ++++++++++++++++++++++
>>  Documentation/devicetree/bindings/arm/cpus.txt     |  1 +
>>  2 files changed, 37 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/arm/bcm/brcm,nsp-cpu-method.txt
>>
>> diff --git a/Documentation/devicetree/bindings/arm/bcm/brcm,nsp-cpu-method.txt b/Documentation/devicetree/bindings/arm/bcm/brcm,nsp-cpu-method.txt
>> new file mode 100644
>> index 0000000..8506da7
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/arm/bcm/brcm,nsp-cpu-method.txt
>> @@ -0,0 +1,36 @@
>> +Broadcom Northstar Plus SoC CPU Enable Method
>> +---------------------------------------------
>> +This binding defines the enable method used for starting secondary
>> +CPUs in the following Broadcom SoCs:
>> +  BCM58522, BCM58525, BCM58535, BCM58622, BCM58623, BCM58625, BCM88312
>> +
>> +The enable method is specified by defining the following required
>> +properties in the "cpus" device tree node:
>> +  - enable-method = "brcm,bcm-nsp-smp";
> 
> As I said already, this is supposed to be per cpu.
> 
>> +  - secondary-boot-reg = <...>;
> 
> And then you might as well move this too.
> 
NS/NSP family of SoCs have maximum of two cores. There would not be a
need for another boot-reg in this family of SoCs. However, I agree, it 
should go to individual CPU nodes. I will do the change in the next patch.
>> +
>> +The secondary-boot-reg property is a u32 value that specifies the
>> +physical address of the register used to request the ROM holding pen
>> +code release a secondary CPU.
>> +
>> +Example:
>> +       cpus {
>> +               #address-cells = <1>;
>> +               #size-cells = <0>;
>> +               enable-method = "brcm,bcm-nsp-smp";
>> +               secondary-boot-reg = <0xffff042c>;
>> +
>> +               cpu0: cpu@0 {
>> +                       device_type = "cpu";
>> +                       compatible = "arm,cortex-a9";
>> +                       next-level-cache = <&L2>;
>> +                       reg = <0>;
>> +               };
>> +
>> +               cpu1: cpu@1 {
>> +                       device_type = "cpu";
>> +                       compatible = "arm,cortex-a9";
>> +                       next-level-cache = <&L2>;
>> +                       reg = <1>;
>> +               };
>> +       };
>> diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt
>> index 91e6e5c..6abe3f3 100644
>> --- a/Documentation/devicetree/bindings/arm/cpus.txt
>> +++ b/Documentation/devicetree/bindings/arm/cpus.txt
>> @@ -191,6 +191,7 @@ nodes to be present and contain the properties described below.
>>                             "allwinner,sun8i-a23"
>>                             "arm,psci"
>>                             "brcm,brahma-b15"
>> +                           "brcm,bcm-nsp-smp"
>>                             "marvell,armada-375-smp"
>>                             "marvell,armada-380-smp"
>>                             "marvell,armada-390-smp"
>> --
>> 2.1.0
>>
Thanks,
Kapil Hali