[PATCH net-next 2/7] net: stmmac: Use NSEC_PER_SEC for hwtstamp calculations

Andrew Halaney ahalaney at redhat.com
Thu Aug 24 11:32:53 PDT 2023


This makes it more clear what unit conversions are happening.

Signed-off-by: Andrew Halaney <ahalaney at redhat.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c | 6 +++---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c     | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
index 6dcf8582a70e..29fd51bb853d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
@@ -36,12 +36,12 @@ static void config_sub_second_increment(void __iomem *ioaddr,
 	 * to mid-range = 2^31 when the remainder of this division is zero,
 	 * which will make the accumulator overflow once every 2 ptp_clock
 	 * cycles, adding twice the number of nanoseconds of a clock cycle :
-	 * 2000000000ULL / ptp_clock.
+	 * 2 * NSEC_PER_SEC / ptp_clock.
 	 */
 	if (value & PTP_TCR_TSCFUPDT)
-		data = (2000000000ULL / ptp_clock);
+		data = (2 * NSEC_PER_SEC / ptp_clock);
 	else
-		data = (1000000000ULL / ptp_clock);
+		data = (NSEC_PER_SEC / ptp_clock);
 
 	/* 0.465ns accuracy */
 	if (!(value & PTP_TCR_TSCTRLSSR))
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 67e4f65f0f68..ba38ca284e26 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -849,7 +849,7 @@ int stmmac_init_tstamp_counter(struct stmmac_priv *priv, u32 systime_flags)
 	stmmac_config_sub_second_increment(priv, priv->ptpaddr,
 					   priv->plat->clk_ptp_rate,
 					   xmac, &sub_second_inc);
-	temp = div_u64(1000000000ULL, sub_second_inc);
+	temp = div_u64(NSEC_PER_SEC, sub_second_inc);
 
 	/* Store sub second increment for later use */
 	priv->sub_second_inc = sub_second_inc;

-- 
2.41.0




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