From: David Brownell <david-b@pacbell.net>
To: Baruch Siach <baruch@tkos.co.il>
Cc: spi-devel-general@lists.sourceforge.net,
Claudio Lanconelli <lanconelli.claudio@eptar.com>,
Shachar Shemesh <shachar@lingnu.com>,
Network development list <netdev@vger.kernel.org>
Subject: Re: [spi-devel-general] [PATCH] enc28j60: Fix sporadic packet loss (correction)
Date: Tue, 2 Dec 2008 13:05:05 -0800 [thread overview]
Message-ID: <200812021305.06083.david-b@pacbell.net> (raw)
In-Reply-To: <20081202085947.GB24490@diamond.tkos.co.il>
On Tuesday 02 December 2008, Baruch Siach wrote:
> Packet data read from the RX buffer the when the RSV is at the end of the RX
> buffer does not warp around. This causes packet loss, as the actual data is
> never read. Fix this by calculating the right packet data location.
>
> Thanks to Shachar Shemesh for suggesting the fix.
>
> Signed-off-by: Baruch Siach <baruch@tkos.co.il>
>
> ---
Seems plausible to me, but network patches should be submitted
to the netdev list. :)
I CC'd them on this reply ... if nobody gives any feedback, I'll
suggest you resubmit there on Friday.
- Dave
p.s. Just for info ... what kind of Linux system are you using
this driver on?
>
> --- drivers/net/enc28j60.c-git 2008-12-02 09:08:24.000000000 +0200
> +++ drivers/net/enc28j60.c 2008-12-02 09:38:33.000000000 +0200
> @@ -568,6 +568,17 @@ static u16 erxrdpt_workaround(u16 next_p
> return erxrdpt;
> }
>
> +/*
> + * Calculate wrap around when reading beyond the end of the RX buffer
> + */
> +static u16 rx_packet_start(u16 ptr)
> +{
> + if (ptr + RSV_SIZE > RXEND_INIT)
> + return (ptr + RSV_SIZE) - RXEND_INIT - 1;
> + else
> + return ptr + RSV_SIZE;
> +}
> +
> static void nolock_rxfifo_init(struct enc28j60_net *priv, u16 start, u16 end)
> {
> u16 erxrdpt;
> @@ -938,8 +949,9 @@ static void enc28j60_hw_rx(struct net_de
> skb->dev = ndev;
> skb_reserve(skb, NET_IP_ALIGN);
> /* copy the packet from the receive buffer */
> - enc28j60_mem_read(priv, priv->next_pk_ptr + sizeof(rsv),
> - len, skb_put(skb, len));
> + enc28j60_mem_read(priv,
> + rx_packet_start(priv->next_pk_ptr),
> + len, skb_put(skb, len));
> if (netif_msg_pktdata(priv))
> dump_packet(__func__, skb->len, skb->data);
> skb->protocol = eth_type_trans(skb, ndev);
>
> --
> ~. .~ Tk Open Systems
> =}------------------------------------------------ooO--U--Ooo------------{=
> - baruch@tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -
>
>
next prev parent reply other threads:[~2008-12-02 21:05 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-12-02 8:59 [PATCH] enc28j60: Fix sporadic packet loss (correction) Baruch Siach
2008-12-02 21:05 ` David Brownell [this message]
2008-12-02 21:35 ` [spi-devel-general] " Baruch Siach
2008-12-02 22:44 ` David Brownell
2008-12-03 6:22 ` [spi-devel-general] " Baruch Siach
2008-12-03 7:04 ` David Brownell
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=200812021305.06083.david-b@pacbell.net \
--to=david-b@pacbell.net \
--cc=baruch@tkos.co.il \
--cc=lanconelli.claudio@eptar.com \
--cc=netdev@vger.kernel.org \
--cc=shachar@lingnu.com \
--cc=spi-devel-general@lists.sourceforge.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).