>On Tue, Aug 22, 2023 at 05:15:25PM -0700, Jakub Kicinski wrote: >> On Sat, 19 Aug 2023 10:31:31 +0800 Rohan G Thomas wrote: >> > + snps,tx-queues-with-coe: >> > + $ref: /schemas/types.yaml#/definitions/uint32 >> > + description: number of TX queues that support TX checksum offloading >> > >> Is it going to be obvious that if not present all queues support >> checksum offload? I think we should document the default. > >This question is debatable: >1. By default the DW xGMAC and DW QoS Eth IP-cores are >synthesized with only the very first Tx queue having Tx COE enabled. >2. If TSO is disabled then the Tx COE can be individually enabled >for each queue available on DW QoS Eth controller and for the very >first N queues on DW xGMAC controller. >3. If TSO is enabled then the Tx COE will be automatically and always >enabled for as many first queues as there are TSO-capable >DMA-channels. >4. At the current state the STMMAC driver assumes that all Tx Queues >support Tx COE. > >The entry 4 can't be changed since we'll risk to catch regressions on >the platforms with no property specified. On the other hand it partly >contradicts to the rest of the entries. I don't know what would be a >correct way to specify the default value in this case. Most likely >just keep the entry 4 and be done with it. > >BTW I just noticed that but the suggested "snps,tx-queues-with-coe" >property semantic will only cover a DW XGMAC-part of the case 2. DW >QoS Eth can be synthesized with Tx COE individually enabled for a >particular queue if TSO is unavailable. Hi Serge, Didn't know about a different IP configuration supported by DW QoS Eth IP. If this is the case, I think we can have a flag 'coe-unsupported' for any TX queue subnode as below. + snps,coe-unsupported: + $ref: /schemas/types.yaml#/definitions/flag + description: + TX checksum offload is unsupported by the TX queue. If TX checksum + offload is requested for a packet to be transmitted through this + TX queue then have a software fallback in the driver for checksum + calculation. If this is okay, I can rework the patch based on this. Covers both DW QoS Eth IP and DW XGMAC IP cases. > >-Serge(y) > >> -- >> pw-bot: cr BR, Rohan
