2024-05-01 16:15:16

by Min Li

Subject: [PATCH net-next v7 3/5] ptp: clockmatrix: dco input-to-output delay is 20 FOD cycles + 8ns

From: Min Li <[email protected]>

Set dco input-to-output delay is 20 FOD cycles + 8ns

Signed-off-by: Min Li <[email protected]>
---
drivers/ptp/ptp_clockmatrix.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c
index d069b6e451ef..21f3a2c179f5 100644
--- a/drivers/ptp/ptp_clockmatrix.c
+++ b/drivers/ptp/ptp_clockmatrix.c
@@ -2165,7 +2165,7 @@ static int configure_channel_pll(struct idtcm_channel *channel)

/*
* Compensate for the PTP DCO input-to-output delay.
- * This delay is 18 FOD cycles.
+ * This delay is 20 FOD cycles + 8ns.
*/
static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
{
@@ -2196,7 +2196,7 @@ static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
fodFreq = (u32)div_u64(m, n);

if (fodFreq >= 500000000)
- return (u32)div_u64(18 * (u64)NSEC_PER_SEC, fodFreq);
+ return (u32)div_u64(20 * (u64)NSEC_PER_SEC, fodFreq) + 8;

return 0;
}
--
2.39.2

2024-05-02 06:51:02

by Horatiu Vultur

Subject: Re: [PATCH net-next v7 3/5] ptp: clockmatrix: dco input-to-output delay is 20 FOD cycles + 8ns

The 05/01/2024 12:03, Min Li wrote:

Hi Min Li,

>
> From: Min Li <[email protected]>
>
> Set dco input-to-output delay is 20 FOD cycles + 8ns

Can you explain why you are doing this change in the commit message?
Is this a fix or just improvement?

>
> Signed-off-by: Min Li <[email protected]>
> ---
> drivers/ptp/ptp_clockmatrix.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c
> index d069b6e451ef..21f3a2c179f5 100644
> --- a/drivers/ptp/ptp_clockmatrix.c
> +++ b/drivers/ptp/ptp_clockmatrix.c
> @@ -2165,7 +2165,7 @@ static int configure_channel_pll(struct idtcm_channel *channel)
>
> /*
> * Compensate for the PTP DCO input-to-output delay.
> - * This delay is 18 FOD cycles.
> + * This delay is 20 FOD cycles + 8ns.
> */
> static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
> {
> @@ -2196,7 +2196,7 @@ static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
> fodFreq = (u32)div_u64(m, n);
>
> if (fodFreq >= 500000000)
> - return (u32)div_u64(18 * (u64)NSEC_PER_SEC, fodFreq);
> + return (u32)div_u64(20 * (u64)NSEC_PER_SEC, fodFreq) + 8;
>
> return 0;
> }
> --
> 2.39.2
>
>

--
/Horatiu

2024-05-03 14:05:20

by Min Li

Subject: RE: [PATCH net-next v7 3/5] ptp: clockmatrix: dco input-to-output delay is 20 FOD cycles + 8ns

>
> Can you explain why you are doing this change in the commit message?
> Is this a fix or just improvement?
>

This is a fix but the first patch of the series is an improvement. But they have
code dependency so I am submitting them together to avoid the hassle

Min