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| author | David S. Miller <davem@davemloft.net> | 2021-03-25 23:31:22 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-25 23:31:22 +0100 |
| commit | efd13b71a3fa31413f8d15342e01d44b60b0a432 (patch) | |
| tree | 2ed1b299e25538c5a60485a1047507b49d3e0ecf /drivers/ptp | |
| parent | hinic: avoid gcc -Wrestrict warning (diff) | |
| parent | Merge branch 'akpm' (patches from Andrew) (diff) | |
| download | linux-efd13b71a3fa31413f8d15342e01d44b60b0a432.tar.xz linux-efd13b71a3fa31413f8d15342e01d44b60b0a432.zip | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/ptp')
| -rw-r--r-- | drivers/ptp/ptp_qoriq.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/ptp/ptp_qoriq.c b/drivers/ptp/ptp_qoriq.c index beb5f74944cd..08f4cf0ad9e3 100644 --- a/drivers/ptp/ptp_qoriq.c +++ b/drivers/ptp/ptp_qoriq.c @@ -189,15 +189,16 @@ int ptp_qoriq_adjfine(struct ptp_clock_info *ptp, long scaled_ppm) tmr_add = ptp_qoriq->tmr_add; adj = tmr_add; - /* calculate diff as adj*(scaled_ppm/65536)/1000000 - * and round() to the nearest integer + /* + * Calculate diff and round() to the nearest integer + * + * diff = adj * (ppb / 1000000000) + * = adj * scaled_ppm / 65536000000 */ - adj *= scaled_ppm; - diff = div_u64(adj, 8000000); - diff = (diff >> 13) + ((diff >> 12) & 1); + diff = mul_u64_u64_div_u64(adj, scaled_ppm, 32768000000); + diff = DIV64_U64_ROUND_UP(diff, 2); tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff; - ptp_qoriq->write(®s->ctrl_regs->tmr_add, tmr_add); return 0; |