Re: [PATCH v4 02/13] dt-bindings: Add bindings for peci-aspeed

[Zev Weiss <zweiss@equinix.com>]

On Wed, Dec 01, 2021 at 02:38:04AM PST, Billy Tsai wrote:
>Hi,
>
>On 2021/11/23, 10:10 PM, "openbmc on behalf of Iwona Winiarska" <openbmc-bounces+billy_tsai=aspeedtech.com@lists.ozlabs.org on behalf of iwona.winiarska@intel.com> wrote:
>
>    Add device tree bindings for the peci-aspeed controller driver.
>
>    >   +  aspeed,clock-divider:
>    >   +    description:
>    >   +      This value determines PECI controller internal clock dividing
>    >   +      rate. The divider will be calculated as 2 raised to the power of
>    >   +      the given value.
>    >   +    $ref: /schemas/types.yaml#/definitions/uint32
>    >   +    minimum: 0
>    >   +    maximum: 7
>    >   +    default: 0
>    >   +
>    >   +  aspeed,msg-timing:
>    >   +    description:
>    >   +      Message timing negotiation period. This value will determine the period
>    >   +      of message timing negotiation to be issued by PECI controller. The unit
>    >   +      of the programmed value is four times of PECI clock period.
>    >   +    $ref: /schemas/types.yaml#/definitions/uint32
>    >   +    minimum: 0
>    >   +    maximum: 255
>    >   +    default: 1
>    >   +
>    >   +  aspeed,addr-timing:
>    >   +    description:
>    >   +      Address timing negotiation period. This value will determine the period
>    >   +      of address timing negotiation to be issued by PECI controller. The unit
>    >   +      of the programmed value is four times of PECI clock period.
>    >   +    $ref: /schemas/types.yaml#/definitions/uint32
>    >   +    minimum: 0
>    >   +    maximum: 255
>    >   +    default: 1
>I suggest deleting these three properties and replacing them with the following
>
>aspeed,peci-bit-time:
>        description:
>          The bit time driven by PECI controller. The unit of the value is Hz.
>    minimum: 2000
>    maximum: 1000000
>
>And the driver should use this property to caculate the appropriate clock-divider,
>msg-timing and addr-timing, instead of exposing hardware registers to dts.
>

Or perhaps just 'bus-frequency' a la i2c-aspeed, gpio-aspeed-sgpio, etc?


Zev