[U-Boot] [PATCH v3 1/8] da850: indicate cache usage disable in config file

[Netagunte, Nagabhushana]

Gentlemen,

If you have no further comments, can you please ACK patches?

Regards,
Nag

On Mon, Aug 29, 2011 at 16:26:57, Netagunte, Nagabhushana wrote:
> Gentlemen,
> 
> We will address cache coherency issues soon after these patches.
> Earlier also, chache was disabled. Only due to new cache management Framework which was added recently, it is explicitly needed to be Indicated to turn off cache. 
> 
> Since fixing the cache coherency issues with EMAC will take some time, I want this patch to go in mainline so that issue doesn't crop up for People who use u-boot.
> 
> Regards,
> Nag
> -----Original Message-----
> From: Laurence Withers [mailto:lwithers at guralp.com]
> Sent: Thursday, August 18, 2011 8:50 PM
> To: Ben Gardiner
> Cc: Netagunte, Nagabhushana; u-boot at lists.denx.de; Rajashekhara, Sudhakar; Hadli, Manjunath; Stefan Roese
> Subject: Re: [U-Boot] [PATCH v3 1/8] da850: indicate cache usage disable in config file
> 
> On Thu, Aug 18, 2011 at 11:13:19AM -0400, Ben Gardiner wrote:
> > I understand that both Laurence and Stefan (cc'd) have confirmed that 
> > there dcache issues with the EMA; I am assuming that the 'issue'
> > results in a delay in tftp'ing...
> 
> No; the issue was that packets were being sent on to the wire with incorrect IP checksums. It twigged that the problem was cache coherency when I put a full hexdump of each outgoing packet in and suddenly the outbound packets started being valid.
> 
> > Disabling the caches will slow down decompression which will slow down 
> > boot overall when booting from flash.
> > 
> > Rather than masking the issue by disabling caches and slowing down 
> > u-boot for it's users perhaps TI should be fixing the EMAC drivers'
> > cache bugs instead?
> 
> Indeed, the correct solution is to properly manage the net buffers with respect to the cache, although I have not attempted that change myself. I have seen some patches start to flow that make changes in drivers to work correctly with caches enabled, such as http://lists.denx.de/pipermail/u-boot/2011-August/098484.html .
> 
> Bye for now,
> -- 
> Laurence Withers, <lwithers at guralp.com>                http://www.guralp.com/
> Direct tel:+447753988197 or tel:+443333408643               Software Engineer
> General support queries: <support at guralp.com>         CMG-DCM CMG-EAM CMG-NAM
>