Re: [PATCH] ata_piix: kill spurious assignment in piix_sata_probe()

[Jeff Garzik <jgarzik@pobox.com>]

Tejun Heo wrote:
> In piix_sata_probe(), mask gets assigned unnecessarily at the
> beginning of the function.  Kill the assignment.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> 
> ---
> 
> This patch is against
> the current upstream (bef4a456b8dc8b3638f4d49a25a89e1467da9483)
> + http://article.gmane.org/gmane.linux.ide/7967
> + http://article.gmane.org/gmane.linux.ide/7968 (2 patches)

applied, though this function needs a further look:

1) We should really:

* enable port X via PCS, if not already
* delay a bit, for SATA device detection
* check 'present' bit
* if nothing present, disable port X via PCS


2) In ICH6 and later, according to the docs:  PCS enable bits should 
always be set, and the port should be controlled via SATA phy registers. 
  As I noted in another email, ICH6+ should support SATA PHY registers 
even if AHCI is disabled.  See bit 9 of SIR (94h) register in ICH6 and 
ICH7, which enables access to SATA PHY regs.


I am hoping that we can make all ICH6/7 use SATA PHY registers, but I am 
worried that in some cases the AHCI BAR may not have been assigned a value.

	Jeff