diff options
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_ptp.c | 17 |
1 files changed, 4 insertions, 13 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ptp.c b/drivers/net/ethernet/intel/i40e/i40e_ptp.c index 57a71fa17ed5..15de918abc41 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c @@ -353,25 +353,16 @@ static int i40e_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) ppb = -ppb; } - freq = I40E_PTP_40GB_INCVAL; - freq *= ppb; - diff = div_u64(freq, 1000000000ULL); + smp_mb(); /* Force any pending update before accessing. */ + freq = I40E_PTP_40GB_INCVAL * READ_ONCE(pf->ptp_adj_mult); + diff = mul_u64_u64_div_u64(freq, (u64)ppb, + 1000000000ULL); if (neg_adj) adj = I40E_PTP_40GB_INCVAL - diff; else adj = I40E_PTP_40GB_INCVAL + diff; - /* At some link speeds, the base incval is so large that directly - * multiplying by ppb would result in arithmetic overflow even when - * using a u64. Avoid this by instead calculating the new incval - * always in terms of the 40GbE clock rate and then multiplying by the - * link speed factor afterwards. This does result in slightly lower - * precision at lower link speeds, but it is fairly minor. - */ - smp_mb(); /* Force any pending update before accessing. */ - adj *= READ_ONCE(pf->ptp_adj_mult); - wr32(hw, I40E_PRTTSYN_INC_L, adj & 0xFFFFFFFF); wr32(hw, I40E_PRTTSYN_INC_H, adj >> 32); |