diff options
| author | Jacob Keller <jacob.e.keller@intel.com> | 2022-07-21 23:29:57 +0200 |
|---|---|---|
| committer | Tony Nguyen <anthony.l.nguyen@intel.com> | 2022-07-28 19:57:06 +0200 |
| commit | abab010f16378c73e14257573bbcbad4378e80c3 (patch) | |
| tree | c6c21974c8188f0827ad22b689315c6778e85d80 /drivers/net/ethernet/intel/e1000e/ptp.c | |
| parent | e1000e: remove unnecessary range check in e1000e_phc_adjfreq (diff) | |
| download | linux-abab010f16378c73e14257573bbcbad4378e80c3.tar.xz linux-abab010f16378c73e14257573bbcbad4378e80c3.zip | |
e1000e: convert .adjfreq to .adjfine
The PTP implementation for the e1000e driver uses the older .adjfreq
method. This method takes an adjustment in parts per billion. The newer
.adjfine implementation uses scaled_ppm. The use of scaled_ppm allows for
finer grained adjustments and is preferred over using the older
implementation.
Make use of mul_u64_u64_div_u64 in order to handle possible overflow of the
multiplication used to calculate the desired adjustment to the hardware
increment value.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/e1000e/ptp.c')
| -rw-r--r-- | drivers/net/ethernet/intel/e1000e/ptp.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/net/ethernet/intel/e1000e/ptp.c b/drivers/net/ethernet/intel/e1000e/ptp.c index 432e04ce8c4e..0e488e4fa5c1 100644 --- a/drivers/net/ethernet/intel/e1000e/ptp.c +++ b/drivers/net/ethernet/intel/e1000e/ptp.c @@ -15,14 +15,16 @@ #endif /** - * e1000e_phc_adjfreq - adjust the frequency of the hardware clock + * e1000e_phc_adjfine - adjust the frequency of the hardware clock * @ptp: ptp clock structure - * @delta: Desired frequency change in parts per billion + * @delta: Desired frequency chance in scaled parts per million * * Adjust the frequency of the PHC cycle counter by the indicated delta from * the base frequency. + * + * Scaled parts per million is ppm but with a 16 bit binary fractional field. **/ -static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta) +static int e1000e_phc_adjfine(struct ptp_clock_info *ptp, long delta) { struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter, ptp_clock_info); @@ -47,9 +49,8 @@ static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta) incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK; - adjustment = incvalue; - adjustment *= delta; - adjustment = div_u64(adjustment, 1000000000); + adjustment = mul_u64_u64_div_u64(incvalue, (u64)delta, + 1000000ULL << 16); incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment); @@ -257,7 +258,7 @@ static const struct ptp_clock_info e1000e_ptp_clock_info = { .n_per_out = 0, .n_pins = 0, .pps = 0, - .adjfreq = e1000e_phc_adjfreq, + .adjfine = e1000e_phc_adjfine, .adjtime = e1000e_phc_adjtime, .gettimex64 = e1000e_phc_gettimex, .settime64 = e1000e_phc_settime, |