On 13/03/2023 23:50, Serge Semin wrote: > Currently none of the MTL Tx Queues QoS-related DT-properties have been > equipped with the proper constraints meanwhile they can be specified at > least based on the corresponding CSR field sizes or the DW (x|xG)MAC > IP-core synthesize parameter constraints. Let's do that: > + snps,tx-queues-to-use - number of Tx queues to utilise is limited with a > number of available queues. DW MAC/GMAC: no queues, DW Eth QoS: <= 8, DW > xGMAC: <= 16. > + snps,weight - Tx Queue/Traffic Class quantum/weight utilised depending > on enabled algorithm for the Data Center Bridging feature: DWRR (up to > 0x1312D0 bytes to add to credit) or WFQ (up to 0x3FFF - least bandwidth) > or WFQ (up to 0x64). DW MAC/GMAC: no queues, DW Eth QoS: <= 0x1312D0, DW > xGMAC: <= 0x1312D0. > + snps,send_slope - Tx Queue/Traffic Class Send-Slope credit value > subtracted from the accumulated credit for the Audio/Video bridging > feature (CBS algorithm, bits per cycle scaled up by 1,024). DW MAC/GMAC: > no queues, DW Eth QoS: <= 0x2000, DW xGMAC: <= 0x3FFF. > + snps,idle_slope - same meaning as snps,send_slope except it's determines > the Idle-Slope credit of CBS algorithm. DW MAC/GMAC: no queues, DW Eth > QoS: <= 0x2000, DW xGMAC: <= 0x8000. > + snps,high_credit/snps,low_credit - maximum and minimum values > accumulated in the credit for the Audio/Video bridging feature (CBS > algorithm, bits scaled up by 1,024). DW MAC/GMAC: no queues, DW Eth > QoS: <= 0x1FFFFFFF, DW xGMAC: <= 0x1FFFFFFF. > + snps,priority - Tx Queue/Traffic Class priority (enabled by the > PFC-packets) limits determined by the VLAN tag PRI field width (it's 7). > DW MAC/GMAC: no queues, DW Eth QoS: 0xff, DW xGMAC: 0xff. > > Since the constraints vary for different IP-cores and the DT-schema is > common for all of them the least restrictive values are chosen. The info > above can be used for the IP-core specific DT-schemas if anybody ever is > bothered with one to create. > > Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> > --- > .../bindings/net/snps,dwmac-generic.yaml | 2 +- > .../devicetree/bindings/net/snps,dwmac.yaml | 24 ++++++++++++++++++- > 2 files changed, 24 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml b/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml > index ae740a1ab213..2974af79511d 100644 > --- a/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml > +++ b/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml > @@ -137,7 +137,7 @@ examples: > snps,send_slope = <0x1000>; > snps,idle_slope = <0x1000>; > snps,high_credit = <0x3E800>; > - snps,low_credit = <0xFFC18000>; > + snps,low_credit = <0x1FC18000>; > snps,priority = <0x1>; > }; > }; > diff --git a/Documentation/devicetree/bindings/net/snps,dwmac.yaml b/Documentation/devicetree/bindings/net/snps,dwmac.yaml > index e5662b1498b7..2ebf7995426b 100644 > --- a/Documentation/devicetree/bindings/net/snps,dwmac.yaml > +++ b/Documentation/devicetree/bindings/net/snps,dwmac.yaml > @@ -250,6 +250,10 @@ properties: > snps,tx-queues-to-use: > $ref: /schemas/types.yaml#/definitions/uint32 > description: number of TX queues to be used in the driver > + default: 1 > + minimum: 1 > + maximum: 16 > + > snps,tx-sched-wrr: > type: boolean > description: Weighted Round Robin > @@ -296,13 +300,16 @@ properties: > snps,tx-sched-wfq: false > snps,tx-sched-dwrr: false > patternProperties: > - "^queue[0-9]$": > + "^queue([0-9]|1[0-5])$": > description: Each subnode represents a queue. > type: object > properties: > snps,weight: > $ref: /schemas/types.yaml#/definitions/uint32 > description: TX queue weight (if using a DCB weight algorithm) > + minimum: 0 > + maximum: 0x1312D0 > + > snps,dcb-algorithm: > type: boolean > description: TX queue will be working in DCB > @@ -315,15 +322,27 @@ properties: > snps,send_slope: > $ref: /schemas/types.yaml#/definitions/uint32 > description: enable Low Power Interface > + minimum: 0 > + maximum: 0x3FFF lowercase hex everywhere. Best regards, Krzysztof
