On 05/03/2024 19:04, Sriram Dash wrote: > On 3/5/2024 10:42 PM, Krzysztof Kozlowski wrote: >> On 05/03/2024 17:57, Sriram Dash wrote: >>> Some target systems allow multiple resources to be managed by firmware. >> >> Which? Why this is so vague... >> > > SA8775 will be using it as pilot. Will include the target name. > >>> On these targets, tasks related to clocks, regulators, resets, and >>> interconnects can be delegated to the firmware, while the remaining >>> responsibilities are handled by Linux. >>> >>> To support the management of partial resources in Linux and leave the rest >>> to firmware, multiple power domains are introduced. Each power domain can >>> manage one or more resources, depending on the specific use case. >>> >>> These power domains handle SCMI calls to the firmware, enabling the >>> activation and deactivation of firmware-managed resources. >>> >>> The driver is responsible for managing multiple power domains and >>> linking them to consumers as needed. Incase there is only single >>> power domain, it is considered to be a standard GDSC hooked on to >>> the qcom dt node which is read and assigned to device structure >>> (by genpd framework) before the driver probe even begins. >> >> This will break the ABI. Sorry, come with an ABI stable solution. >> > > The plan is to include multiple power-domains and fw-managed > property or similar in the device tree and fw-managed property > will be deciding if we need some resource management offloaded > to firmware. So, OS is always in control here. The decision > making will be done in the drivers. Also, there will be no > separate vendor hooks. This does not answer ABI breakage. Also, I don't have a clue what are "vendor hooks". Best regards, Krzysztof
