Re: [PATCH net-next] bindings: net: stmmac: correctify note about LPI interrupt

From: David Miller
Date: Sat Nov 11 2017 - 05:29:58 EST


From: Niklas Cassel <niklas.cassel@xxxxxxxx>
Date: Thu, 9 Nov 2017 18:09:26 +0100

> There are two different combined signal for various interrupt events:
> In EQOS-CORE and EQOS-MTL configurations, mci_intr_o is the interrupt
> signal.
> In EQOS-DMA, EQOS-AHB and EQOS-AXI configurations, these interrupt events
> are combined with the events in the DMA on the sbd_intr_o signal.
>
> Depending on configuration, the device tree irq "macirq" will refer to
> either mci_intr_o or sbd_intr_o.
>
> The databook states:
> "The MAC generates the LPI interrupt when the Tx or Rx side enters or exits
> the LPI state. The interrupt mci_intr_o (sbd_intr_o in certain
> configurations) is asserted when the LPI interrupt status is set.
>
> When the MAC exits the Rx LPI state, then in addition to the mci_intr_o
> (sbd_intr_o in certain configurations), the sideband signal lpi_intr_o is
> asserted.
>
> If you do not want to gate-off the application clock during the Rx LPI
> state, you can leave the lpi_intr_o signal unconnected and use the
> mci_intr_o (sbd_intr_o in certain configurations) signal to detect Rx LPI
> exit."
>
> Since the "macirq" is always raised when Tx or Rx enters/exits the LPI
> state, "eth_lpi" must therefore refer to lpi_intr_o, which is only raised
> when Rx exits the LPI state. Update the DT binding description to reflect
> reality.
>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>

Applied.