Re: [PATCH v8 0/3] firmware: ti_sci: Partial-IO support

[Nishanth Menon <nm@ti.com>]

On 16:37-20251001, Markus Schneider-Pargmann (TI.com) wrote:
> Hi,
> 
> This series adds support for Partial-IO to the ti-sci driver,
> implementing the firmware interface necessary to enter this low power
> state. It processes the wakeup-source properties from the devicetree and
> communicates with the system firmware to enter Partial-IO mode when
> appropriate wakeup sources are enabled.
> 
> Partial-IO Overview
> ------------------
> Partial-IO is a low power system state in which nearly everything is
> turned off except the pins of the CANUART group (mcu_mcan0, mcu_mcan1,
> wkup_uart0 and mcu_uart0). These devices can trigger a wakeup of the
> system on pin activity. Note that this does not resume the system as the
> DDR is off as well. So this state can be considered a power-off state
> with wakeup capabilities.
> 
> A documentation can also be found in section 6.2.4 in the TRM:
>   https://www.ti.com/lit/pdf/spruiv7
> 
> Implementation Details
> ----------------------
> The complete Partial-IO feature requires three coordinated series, each
> handling a different aspect of the implementation:
> 
> 1. m_can driver series: Implements device-specific wakeup functionality
>    for m_can devices, allowing them to be set as wakeup sources.
>    https://gitlab.baylibre.com/msp8/linux/-/tree/topic/mcan-wakeup-source/v6.17?ref_type=heads
>    https://lore.kernel.org/r/20250812-topic-mcan-wakeup-source-v6-12-v8-0-6972a810d63b@baylibre.com
> 
> 2. Devicetree series: Defines system states and wakeup sources in the
>    devicetree for am62, am62a and am62p.
>    https://gitlab.baylibre.com/msp8/linux/-/tree/topic/am62-dt-partialio/v6.17?ref_type=heads
>    https://lore.kernel.org/r/20250812-topic-am62-dt-partialio-v6-15-v2-0-25352364a0ac@baylibre.com
> 
> 3. This series (TI-SCI firmware): Implements the firmware interface to
>    enter Partial-IO mode when appropriate wakeup sources are enabled.

If this is the order of dependencies, I guess the series has to wait
till CAN driver changes are merged? did I get that right?

Also surprised that the DT series is second in the dependency.. usually
dts changes occur the last. but anyways..

[...]

-- 
Regards,
Nishanth Menon
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