On 10/09/2014 04:47 PM, Thomas Petazzoni wrote:
Well, I initially remember that the original driver coming from Marvell was using the HW PHY stuff, and that I changed that because it would not integrate well with the kernel libphy. A drawback of this is that because the hardware has built-in PHY polling which triggers a MAC interrupt when the PHY status changes, they typically don't wire up the PHY interrupt. Therefore, since we're not able to use the MAC interrupt for PHY event notifications, we rely on software PHY polling, which means that link up / link down events take a few seconds to be noticed by the kernel. Unfortunately, I don't think the hardware allows to use the hardware PHY polling to get link changes interrupt, but not let the hardware configure the PHY itself.
Yeah, but that HW PHY stuff really only works properly with standard compliant PHYs. In particular, the integrated Marvell PHY in Marvell Berlin SoCs does not seem to reflect PHY status on BMCR properly /sigh/. Anyway, I think we can live with PHY polling. BTW, one thing I noticed here is that libphy calls adjust_link over-and-over again although nothing has changed. I guess we can just add some before/after comparison in the libphy state machine and only call adjust_link when something has changed. I'll have to look closer at the state machine first and maybe Florian can comment on this, too. Sebastian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
