Re: [PATCH v2 11/11] interconnect: Add devfreq support

From: Georgi Djakov
Date: Mon Jun 17 2019 - 11:48:58 EST

Hi Saravana,

On 6/14/19 07:17, Saravana Kannan wrote:
> Add a icc_create_devfreq() and icc_remove_devfreq() to create and remove
> devfreq devices for interconnect paths. A driver can create/remove devfreq
> devices for the interconnects needed for its device by calling these APIs.
> This would allow various devfreq governors to work with interconnect paths
> and the device driver itself doesn't have to actively manage the bandwidth
> votes for the interconnects.

Thanks for the patches, but creating devfreq devices for each interconnect path
seems odd to me - at least for consumers that already use a governor. So for DDR
scaling for example, are you suggesting that we add a devfreq device from the
cpufreq driver in order to scale the interconnect between CPU<->DDR? Also if the
GPU is already using devfreq, should we add a devfreq per each interconnect
path? What would be the benefit in this case - using different governors for
bandwidth scaling maybe?