netdev - RE: [PATCH net-next 04/13] ravb: Add ptp_cfg_active to struct ravb_hw

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <OS0PR01MB5922F8114A505A33F7A47EB586C79@OS0PR01MB5922.jpnprd01.prod.outlook.com>
Date:   Thu, 26 Aug 2021 10:52:34 +0000
From:   Biju Das <biju.das.jz@...renesas.com>
To:     Sergey Shtylyov <s.shtylyov@....ru>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
CC:     Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@...renesas.com>,
        Andrew Lunn <andrew@...n.ch>,
        Sergei Shtylyov <sergei.shtylyov@...il.com>,
        Geert Uytterhoeven <geert+renesas@...der.be>,
        Adam Ford <aford173@...il.com>,
        Yoshihiro Shimoda <yoshihiro.shimoda.uh@...esas.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-renesas-soc@...r.kernel.org" 
        <linux-renesas-soc@...r.kernel.org>,
        Chris Paterson <Chris.Paterson2@...esas.com>,
        Biju Das <biju.das@...renesas.com>
Subject: RE: [PATCH net-next 04/13] ravb: Add ptp_cfg_active to struct
 ravb_hw_info

Hi Sergei,

> Subject: Re: [PATCH net-next 04/13] ravb: Add ptp_cfg_active to struct
> ravb_hw_info
> 
> On 26.08.2021 13:34, Biju Das wrote:
> 
> [...]
> >>>>> There are some H/W differences for the gPTP feature between R-Car
> >>>>> Gen3, R-Car Gen2, and RZ/G2L as below.
> >>>>>
> >>>>> 1) On R-Car Gen3, gPTP support is active in config mode.
> >>>>> 2) On R-Car Gen2, gPTP support is not active in config mode.
> >>>>> 3) RZ/G2L does not support the gPTP feature.
> >>>>>
> >>>>> Add a ptp_cfg_active hw feature bit to struct ravb_hw_info for
> >>>>> supporting gPTP active in config mode for R-Car Gen3.
> >>>>
> >>>>      Wait, we've just done this ion the previous patch!
> >>>>
> >>>>> This patch also removes enum ravb_chip_id, chip_id from both
> >>>>> struct ravb_hw_info and struct ravb_private, as it is unused.
> >>>>>
> >>>>> Signed-off-by: Biju Das <biju.das.jz@...renesas.com>
> >>>>> Reviewed-by: Lad Prabhakar
> >>>>> <prabhakar.mahadev-lad.rj@...renesas.com>
> >>>>> ---
> >>>>>    drivers/net/ethernet/renesas/ravb.h      |  8 +-------
> >>>>>    drivers/net/ethernet/renesas/ravb_main.c | 12 +++++-------
> >>>>>    2 files changed, 6 insertions(+), 14 deletions(-)
> >>>>>
> >>>>> diff --git a/drivers/net/ethernet/renesas/ravb.h
> >>>>> b/drivers/net/ethernet/renesas/ravb.h
> >>>>> index 9ecf1a8c3ca8..209e030935aa 100644
> >>>>> --- a/drivers/net/ethernet/renesas/ravb.h
> >>>>> +++ b/drivers/net/ethernet/renesas/ravb.h
> >>>>> @@ -979,17 +979,11 @@ struct ravb_ptp {
> >>>>>    	struct ravb_ptp_perout perout[N_PER_OUT];  };
> >>>>>
> >>>>> -enum ravb_chip_id {
> >>>>> -	RCAR_GEN2,
> >>>>> -	RCAR_GEN3,
> >>>>> -};
> >>>>> -
> >>>>>    struct ravb_hw_info {
> >>>>>    	const char (*gstrings_stats)[ETH_GSTRING_LEN];
> >>>>>    	size_t gstrings_size;
> >>>>>    	netdev_features_t net_hw_features;
> >>>>>    	netdev_features_t net_features;
> >>>>> -	enum ravb_chip_id chip_id;
> >>>>>    	int stats_len;
> >>>>>    	size_t max_rx_len;
> >>>>
> >>>>      I would put the above in a spearte patch...
> >>
> >>      Separate. :-)
> >>
> >>>>>    	unsigned aligned_tx: 1;
> >>>>> @@ -999,6 +993,7 @@ struct ravb_hw_info {
> >>>>>    	unsigned tx_counters:1;		/* E-MAC has TX counters */
> >>>>>    	unsigned multi_irqs:1;		/* AVB-DMAC and E-MAC has
> >> multiple
> >>>> irqs */
> >>>>>    	unsigned no_ptp_cfg_active:1;	/* AVB-DMAC does not support
> >> gPTP
> >>>> active in config mode */
> >>>>> +	unsigned ptp_cfg_active:1;	/* AVB-DMAC has gPTP support
> active in
> >>>> config mode */
> >>>>
> >>>>      Huh?
> >>>>
> >>>>>    };
> >>>>>
> >>>>>    struct ravb_private {
> >>>> [...]
> >>>>> @@ -2216,7 +2213,7 @@ static int ravb_probe(struct platform_device
> >>>> *pdev)
> >>>>>    	INIT_LIST_HEAD(&priv->ts_skb_list);
> >>>>>
> >>>>>    	/* Initialise PTP Clock driver */
> >>>>> -	if (info->chip_id != RCAR_GEN2)
> >>>>> +	if (info->ptp_cfg_active)
> >>>>>    		ravb_ptp_init(ndev, pdev);
> >>>>
> >>>>      What's that? Didn't you touch this lie in patch #3?
> >>>>
> >>>>      This seems lie a NAK bait... :-(
> >>>
> >>> Please refer the original patch[1] which introduced gPTP support
> >>> active
> >> in config mode.
> >>> I am sure this will clear all your doubts.
> >>
> >>      It hasn't. Why do we need 2 bit fields (1 "positive" and 1
> >> "negative") for the same feature is beyond me.
> >
> > The reason is mentioned in commit description, Do you agree 1, 2 and 3
> mutually exclusive?
> >
> > 1) On R-Car Gen3, gPTP support is active in config mode.
> > 2) On R-Car Gen2, gPTP support is not active in config mode.
> > 3) RZ/G2L does not support the gPTP feature.
> 
>     No, (1) includes (2).

patch[1] is for supporting gPTP support active in config mode.

Do you agree GAC register(gPTP active in Config) bit in AVB-DMAC mode register(CCC) present only in R-Car Gen3?

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/net/ethernet/renesas/ravb_main.c?h=next-20210825&id=f5d7837f96e53a8c9b6c49e1bc95cf0ae88b99e8

Regards,
Biju

> 
> [...]
> 
> > Regards,
> > Biju
> 
> [...]
> 
> MBR, Sergey