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From: Marek Vasut <marex@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH v2 2/2] net: fec_mxc: Do not error out when FEC_TBD_READY
Date: Thu, 21 Aug 2014 07:02:28 +0200	[thread overview]
Message-ID: <201408210702.29047.marex@denx.de> (raw)
In-Reply-To: <b637ef6996e84270bf8ebbc8b43a0c07@BN1PR0301MB0723.namprd03.prod.outlook.com>

On Thursday, August 21, 2014 at 06:11:16 AM, Ye Li wrote:
> The TDAR bit is set when the descriptors are all out from TX ring, but the
> descriptor properly is in transmitting not READY.

I don't quite understand this, can you please rephrase ?

> These are two signals,
> and in Ic simulation, we found the TDAR always clear prior than the READY
> bit of last BD. In mx6solox, we use a latest version of FEC IP. It looks
> the intrinsic behave of TDAR bit is changed in this FEC version, not any
> bug in mx6sx.

OK, so this behavior is isolated to MX6SX and newer. Then any adjustment should 
focus solely on MX6SX and newer.

> There are some solutions for this problem. Which would be acceptable?
> 1. Change the TDAR polling to checking the READY bit in BD.

This would return the cache-grinding, so this is not nice.

> 2. Add polling the READY bit of BD after the TDAR polling.

If this would be isolated to MX6SX only, then that is doable.

> 3. Add a delay after the TDAR polling.

This is just work.

> 
> Best regards,
> Ye Li

Thanks for clarifying. Also, can you please stop top-posting when sending to 
mailing lists ?

Best regards,
Marek Vasut

  reply	other threads:[~2014-08-21  5:02 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-20 21:24 [U-Boot] [PATCH v2 1/2] net: fec_mxc: Adjust RX DMA alignment for mx6solox Fabio Estevam
2014-08-20 21:24 ` [U-Boot] [PATCH v2 2/2] net: fec_mxc: Do not error out when FEC_TBD_READY Fabio Estevam
2014-08-20 21:34   ` Otavio Salvador
2014-08-21  3:47     ` Marek Vasut
2014-08-21  3:53   ` Marek Vasut
2014-08-21  4:11     ` Ye Li
2014-08-21  5:02       ` Marek Vasut [this message]
2014-08-21  7:57         ` Stefano Babic
2014-08-21  8:35           ` Li Ye-B37916
2014-08-21 11:39           ` Marek Vasut
2014-08-21  3:44 ` [U-Boot] [PATCH v2 1/2] net: fec_mxc: Adjust RX DMA alignment for mx6solox Li Ye-B37916
2014-08-21  3:51 ` Marek Vasut
2014-08-21  6:03 ` Stefan Roese
2014-08-21 12:08   ` Fabio Estevam
2014-08-21  8:01 ` Stefano Babic
2014-08-21 11:55   ` Fabio Estevam

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