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SubjectRe: [PATCH v8 1/2] of: Documentation: Specify local APIC ID in "reg"
On Thu, Mar 22, 2018 at 4:35 PM, Ivan Gorinov <ivan.gorinov@intel.com> wrote:
> Use the "reg" property to specify the processor's local APIC ID instead of
> setting it to the CPU node index in Device Tree.
>
> Local APIC ID is assigned by hardware and visible in the APIC ID register.
> Some processor models allow APIC ID to be changed by software, but CPUID
> instruction executed with %eax = 0x0b always returns the initial ID in %edx.
>
> Local APIC ID does not match the node index in many systems.
>
> Signed-off-by: Ivan Gorinov <ivan.gorinov@intel.com>
> ---
> Documentation/devicetree/bindings/x86/ce4100.txt | 37 ++++++++++++++++++------
> 1 file changed, 28 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/x86/ce4100.txt b/Documentation/devicetree/bindings/x86/ce4100.txt
> index b49ae59..4bbfed1 100644
> --- a/Documentation/devicetree/bindings/x86/ce4100.txt
> +++ b/Documentation/devicetree/bindings/x86/ce4100.txt
> @@ -7,17 +7,36 @@ Many of the "generic" devices like HPET or IO APIC have the ce4100
> name in their compatible property because they first appeared in this
> SoC.
>
> -The CPU node
> -------------
> - cpu@0 {
> - device_type = "cpu";
> - compatible = "intel,ce4100";
> - reg = <0>;
> - lapic = <&lapic0>;
> +The CPU nodes
> +-------------
> +
> + cpus {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + cpu@0x00 {

As I mentioned on prior versions, drop the '0x' and leading zeros.

Otherwise,

Reviewed-by: Rob Herring <robh@kernel.org>

> + device_type = "cpu";
> + compatible = "intel,ce4100";
> + reg = <0x00>;
> + };
> +
> + cpu@0x02 {
> + device_type = "cpu";
> + compatible = "intel,ce4100";
> + reg = <0x02>;
> + };
> };
>
> -The reg property describes the CPU number. The lapic property points to
> -the local APIC timer.
> +A "cpu" node describes one logical processor (hardware thread).
> +
> +Required properties:
> +
> +- device_type
> + Device type, must be "cpu".
> +
> +- reg
> + Local APIC ID, the unique number assigned to each processor by
> + system hardware.
>
> The SoC node
> ------------
> --
> 2.7.4
>

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