Re: [Patch net-next v1 01/12] net: dsa: microchip: ptp: add the posix clock support

[Christian Eggers <ceggers@arri.de>]

On Monday, 28 November 2022, 15:49:33 CET, Pavan Chebbi wrote:
> On Mon, Nov 28, 2022 at 4:03 PM Arun Ramadoss
> <arun.ramadoss@microchip.com> wrote:
> 
> > diff --git a/drivers/net/dsa/microchip/ksz_ptp_reg.h b/drivers/net/dsa/microchip/ksz_ptp_reg.h
> > new file mode 100644
> > index 000000000000..e578a0006ecf
> > --- /dev/null
> > +++ b/drivers/net/dsa/microchip/ksz_ptp_reg.h
> > @@ -0,0 +1,57 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/* Microchip KSZ PTP register definitions
> > + * Copyright (C) 2022 Microchip Technology Inc.
> > + */
> > +
> > +#ifndef __KSZ_PTP_REGS_H
> > +#define __KSZ_PTP_REGS_H
> > +
> > +/* 5 - PTP Clock */
> > +#define REG_PTP_CLK_CTRL               0x0500
> > +
> > +#define PTP_STEP_ADJ                   BIT(6)
> > +#define PTP_STEP_DIR                   BIT(5)
> > +#define PTP_READ_TIME                  BIT(4)
> > +#define PTP_LOAD_TIME                  BIT(3)
> 
> PTP_WRITE_TIME sounds more intuitive than PTP_LOAD_TIME?
PTP_LOAD_TIME has been derived from the data sheet:

-------------8<--------------
PTP Clock Load
--------------
Setting this bit will cause the PTP clock to be loaded with the time value in
registers 0x0502 to 0x050B.
------------->8--------------

I would also prefer PTP_WRITE_TIME. But is it ok to deviate from data sheet?

> Also I see that all the #defines are introduced in this patch, some of
> which are used later. It is a good idea to introduce the #defines in
> the same patches where they are being used for the first time.
> I will be looking at the entire series but am responding to this now.
> 
> > +#define PTP_CLK_ADJ_ENABLE             BIT(2)
> > +#define PTP_CLK_ENABLE                 BIT(1)
> > +#define PTP_CLK_RESET                  BIT(0)
> > +
> > +#define REG_PTP_RTC_SUB_NANOSEC__2     0x0502
> > +
> > +#define PTP_RTC_SUB_NANOSEC_M          0x0007
> > +#define PTP_RTC_0NS                    0x00
> > +
> > +#define REG_PTP_RTC_NANOSEC            0x0504
> > +#define REG_PTP_RTC_NANOSEC_H          0x0504
> > +#define REG_PTP_RTC_NANOSEC_L          0x0506
> > +
> > +#define REG_PTP_RTC_SEC                        0x0508
> > +#define REG_PTP_RTC_SEC_H              0x0508
> > +#define REG_PTP_RTC_SEC_L              0x050A
> > +
> > +#define REG_PTP_SUBNANOSEC_RATE                0x050C
> > +#define REG_PTP_SUBNANOSEC_RATE_H      0x050C
> > +#define PTP_SUBNANOSEC_M               0x3FFFFFFF
> > +
> > +#define PTP_RATE_DIR                   BIT(31)
> > +#define PTP_TMP_RATE_ENABLE            BIT(30)
> > +
> > +#define REG_PTP_SUBNANOSEC_RATE_L      0x050E
> > +
> > +#define REG_PTP_RATE_DURATION          0x0510
> > +#define REG_PTP_RATE_DURATION_H                0x0510
> > +#define REG_PTP_RATE_DURATION_L                0x0512
> > +
> > +#define REG_PTP_MSG_CONF1              0x0514
> > +
> > +#define PTP_802_1AS                    BIT(7)
> > +#define PTP_ENABLE                     BIT(6)
> > +#define PTP_ETH_ENABLE                 BIT(5)
> > +#define PTP_IPV4_UDP_ENABLE            BIT(4)
> > +#define PTP_IPV6_UDP_ENABLE            BIT(3)
> > +#define PTP_TC_P2P                     BIT(2)
> > +#define PTP_MASTER                     BIT(1)
> > +#define PTP_1STEP                      BIT(0)
> > +
> > +#endif
> > --
> > 2.36.1
> >
>