Re: [PATCH] updates to Vitesse SATA driver

On Wed, Sep 29, 2004 at 11:28:19PM -0400, Jeff Garzik wrote:

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On Wed, 29 Sep 2004 18:19:40 -0400, Jeff Garzik [off-list ref] wrote:

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So where did the discussion on this patch land?

The only part that made sense to me was the LED patch, which should
just be a single line of code.

So maybe you or Dave could be convinced to roll that into a separate 
patch, since we have consensus on that item?

Since I'm just as happy without it, I'll let Dave do it  :-)

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Obviosly if it is working on IA32 or IA64, this code must be only
scanning device 0 per port and not device 1. Not sure why it is only
scanning 1 device on IA platforms, but both on XScale. Either way we
have a corner case here that should be addressed....

Jeff, I don't remember how libata knows how many devices a port
can have.  Which field is it?

By default it only scans device 0, since SATA is a point-to-point 
connection where there is no possibility for more than one device :)

However, some hardware chooses to emulate master/slave mode.  Use of 
this, particularly on Vitesse/Intel, is highly discouraged in favor of 
DPA mode.  I would prefer to not support master/slave mode at all.

Technically speaking, one sets the ATA_FLAG_SLAVE_POSS flag to tell the 
libata core to scan for device 1.

If we are talking about Port Multipliers, those aren't supported at all yet.

	Jeff

So there's something amiss with the XScale, then, it appears.  They
also were having trouble with byte writes to the interrupt mask
register.  That also seems to be a problem unique to that platform.

jeremy