Re: [PATCH net-next RFC 3/3] net/mlx5: Add FW upgrade reset support

From: Jakub Kicinski
Date: Wed Jan 15 2020 - 10:01:48 EST


On Tue, 14 Jan 2020 17:55:28 +0200, Moshe Shemesh wrote:
> Add support for FW upgrade reset.
> On devlink reload the driver checks if there is a FW stored pending
> upgrade reset. In such case the driver will set the device to FW upgrade
> reset on next PCI link toggle and do link toggle after unload.
>
> To do PCI link toggle, the driver ensures that no other device ID under
> the same bridge by checking that all the PF functions under the same PCI
> bridge have same device ID. If no other device it uses PCI bridge link
> control to turn link down and up.
>
> Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>

I'd have a slight preference for the reset to be an explicit command
rather than something the driver does automatically on the reload if
there are pending changes. Won't there ever be scenarios where users
just want to hard reset the device for their own reason?

If multiple devices under one bridge are a real concern (or otherwise
interdependencies) would it make sense to mark the devices as "reload
pending" and perform the reloads once all devices in the group has this
mark set?