Messages in this thread | | | From | Shenwei Wang <> | Subject | RE: [EXT] Re: [PATCH v3 net 2/2] net: stmmac: dwmac-imx: pause the TXC clock in fixed-link | Date | Tue, 1 Aug 2023 17:06:46 +0000 |
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> -----Original Message----- > From: Russell King <linux@armlinux.org.uk> > Sent: Tuesday, August 1, 2023 7:57 AM > To: Johannes Zink <j.zink@pengutronix.de> > Cc: Shenwei Wang <shenwei.wang@nxp.com>; David S. Miller > <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub > Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Maxime > Coquelin <mcoquelin.stm32@gmail.com>; Shawn Guo <shawnguo@kernel.org>; > Sascha Hauer <s.hauer@pengutronix.de>; Neil Armstrong > <neil.armstrong@linaro.org>; Kevin Hilman <khilman@baylibre.com>; Vinod > Koul <vkoul@kernel.org>; Chen-Yu Tsai <wens@csie.org>; Jernej Skrabec > <jernej.skrabec@gmail.com>; Samuel Holland <samuel@sholland.org>; > Giuseppe Cavallaro <peppe.cavallaro@st.com>; Alexandre Torgue > <alexandre.torgue@foss.st.com>; Jose Abreu <joabreu@synopsys.com>; > Pengutronix Kernel Team <kernel@pengutronix.de>; Fabio Estevam > <festevam@gmail.com>; dl-linux-imx <linux-imx@nxp.com>; Jerome Brunet > <jbrunet@baylibre.com>; Martin Blumenstingl > <martin.blumenstingl@googlemail.com>; Bhupesh Sharma > <bhupesh.sharma@linaro.org>; Nobuhiro Iwamatsu > <nobuhiro1.iwamatsu@toshiba.co.jp>; Simon Horman > <simon.horman@corigine.com>; Andrew Halaney <ahalaney@redhat.com>; > Bartosz Golaszewski <bartosz.golaszewski@linaro.org>; Wong Vee Khee > <veekhee@apple.com>; Revanth Kumar Uppala <ruppala@nvidia.com>; Jochen > Henneberg <jh@henneberg-systemdesign.com>; netdev@vger.kernel.org; linux- > stm32@st-md-mailman.stormreply.com; linux-arm-kernel@lists.infradead.org; > linux-kernel@vger.kernel.org; linux-amlogic@lists.infradead.org; > imx@lists.linux.dev; Frank Li <frank.li@nxp.com> > Subject: [EXT] Re: [PATCH v3 net 2/2] net: stmmac: dwmac-imx: pause the TXC > clock in fixed-link > > Caution: This is an external email. Please take care when clicking links or > opening attachments. When in doubt, report the message using the 'Report this > email' button > > > On Tue, Aug 01, 2023 at 02:47:46PM +0200, Johannes Zink wrote: > > Hi Shenwei, > > > > thanks for your patch. > > > > On 7/31/23 18:19, Shenwei Wang wrote: > > > When using a fixed-link setup, certain devices like the SJA1105 > > > require a small pause in the TXC clock line to enable their internal > > > tunable delay line (TDL). > > > > If this is only required for some devices, is it safe to enforce this > > behaviour unconditionally for any kind of fixed link devices connected > > to the MX93 EQOS or could this possibly break for other devices? > > This same point has been raised by Andrew Halaney in message-id > <4govb566nypifbtqp5lcbsjhvoyble5luww3onaa2liinboguf@4kgihys6vhrg> > and Fabio Estevam in message-id > > <CAOMZO5ANQmVbk_jy7qdVtzs3716FisT2c72W+3WZyu7FoAochw@mail.gmail. > com> > but we don't seem to have any answer for it. > Hi Russell,
I hope you have thoroughly read all of my earlier responses, as I believe I already addressed this question. I'm happy to clarify further, but kindly avoid unsubstantiated comments.
https://lore.kernel.org/imx/20230727152503.2199550-1-shenwei.wang@nxp.com/T/#m08da3797a056d4d8ea4c1d8956b445ae967e7cfa " Yes, that's the purpose because it won't hurt even the other side is not SJA1105."
> Also, the patch still uses wmb() between the write and the delay, and as Will > Deacon pointed out in his message, message-id > <20230728153611.GH21718@willie-the-truck> > this is not safe, yet still a new version was sent. >
Can we conclude that even without the wmb() here, the desired delay time between operations can still be ensured?
Thanks, Shenwei
> It seems the author of these patches is pretty resistant to comments, and has > shown that when I was requesting changes - it was an awful struggle to get > changes made. I'm now of the opinion that I really can't be bothered to review > these patches, precisely because feedback is clearly not welcome or if welcome, > apparently acted upon. > > -- > RMK's Patch system: > https://www.ar/ > mlinux.org.uk%2Fdeveloper%2Fpatches%2F&data=05%7C01%7Cshenwei.wang > %40nxp.com%7Ce65ab380ff5b4748da5308db928ec751%7C686ea1d3bc2b4c6fa > 92cd99c5c301635%7C0%7C0%7C638264914150592989%7CUnknown%7CTWFp > bGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6 > Mn0%3D%7C3000%7C%7C%7C&sdata=%2FzSqRqJFRQljX6ky3XJvfkMH9PwgOstb > w8HpEppYOIM%3D&reserved=0 > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
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