RE: ata4.00: failed to get Identify Device Data, Emask 0x1

From: Huang, Shane
Date: Thu Oct 18 2012 - 05:11:18 EST

> Agree. If NCQ does not imply support of this log page, we should
> definitely refine the check condition used here.
> I suppose Shane will take care of this, but if he doesn't, I'll do that
> at a later time.

I tried word 78 bit 5(Hardware Feature Control) which does not work,
it is 0 on my HDD sample with log 30h page 08h and DevSlp supported.

Seems that word 78 bit 5 is only the sufficient condition, not the
essential condition. Do you guys have suggestion?

Quoting SATA spec:
> Word 78: Serial ATA features supported
> Bit 5 If bit 5 is set to one, then Hardware Feature Control is
> supported (see 13.10). If bit 5 is cleared to zero, then Hardware
> Feature Control is not supported and IDENTIFY DEVICE data
> word 79 bit 5 shall be cleared to zero.
> If Hardware Feature Control is supported, then:
> a) IDENTIFY DEVICE data word 78 bit 5 (see shall be
> set to one;
> b) the SET FEATURES Select Hardware Feature Control subcommand
> shall be supported (see 13.3.8);
> c) page 08h of the Identify Device Data log (see 13.7.7) shall
> be supported;


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