Messages in this thread | | | Date | Sat, 23 Nov 2019 19:02:09 -0800 | From | Jakub Kicinski <> | Subject | Re: [net-next] enetc: add support Credit Based Shaper(CBS) for hardware offload |
| |
On Fri, 22 Nov 2019 07:17:18 +0000, Po Liu wrote: > + if (tc == prio_top) { > + max_interference_size = port_frame_max_size * 8; > + } else { > + u32 m0, ma, r0, ra; > + > + m0 = port_frame_max_size * 8; > + ma = enetc_port_rd(&si->hw, ENETC_PTCMSDUR(prio_top)) * 8; > + ra = enetc_get_cbs_bw(&si->hw, prio_top) * > + port_transmit_rate * 10000ULL; > + r0 = port_transmit_rate * 1000000ULL; > + max_interference_size = m0 + ma + (u64)ra * m0 / (r0 - ra); > + } > + > + /* hiCredit bits calculate by: > + * > + * maxSizedFrame * (idleSlope/portTxRate) > + */ > + hi_credit_bit = max_interference_size * bw / 100; > + > + /* hiCredit bits to hiCredit register need to calculated as: > + * > + * (enetClockFrequency / portTransmitRate) * 100 > + */ > + hi_credit_reg = (ENETC_CLK * 100ULL) * hi_credit_bit > + / (port_transmit_rate * 1000000ULL);
Hi! The patch looks good to me, but I'm concerned about those 64bit divisions here. Don't these need to be div_u64() & co.? Otherwise we may see one of the:
ERROR: "__udivdi3" [drivers/net/ethernet/freescale/enetc/fsl-enetc.ko] undefined!
messages from the build bot..
I could be wrong, I haven't actually tested..
| |