Re: [PATCH net v2] net: ti: icssg-prueth: Fix r30 CMDs bitmasks

From: Andrew Lunn
Date: Mon Oct 16 2023 - 12:28:43 EST


On Mon, Oct 16, 2023 at 09:45:25PM +0530, MD Danish Anwar wrote:
> The bitmask for EMAC_PORT_DISABLE and EMAC_PORT_FORWARD has been changed
> in the ICSSG firmware REL.PRU-ICSS-ETHERNET-SWITCH_02.02.12.05.
>
> The current bitmasks are wrong and as a result EMAC_PORT_DISABLE and
> EMAC_PORT_FORWARD commands doesn not work.
> Update r30 commands to use the same bitmask as used by the ICSSG firmware
> REL.PRU-ICSS-ETHERNET-SWITCH_02.02.12.05.
>
> These bitmasks are not backwards compatible. This will work with
> firmware version REL.PRU-ICSS-ETHERNET-SWITCH_02.02.12.05 and above but
> not with lower firmware versions.

Breaking backwards compatibility is generally not allowed.

As far as i understand the driver, it loads whatever version of
firmware is available. It does not ask for a specific version. So you
should ask the firmware what version it is, and then handle the
bitmask as appropriate.

How many different versions of REL.PRU-ICSS-ETHERNET-SWITCH have been
released? They don't appear to be part of linux-firmware.git :-(

Andrew

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