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

From: Zev Weiss
Date: Wed Dec 01 2021 - 22:09:12 EST


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@xxxxxxxxxxxxxxxx on behalf of iwona.winiarska@xxxxxxxxx> 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