Re: [PATCH] Add pci class code for SATA

[Conke Hu]

On 12/20/06, Jeff Garzik <jeff@xxxxxxxxxx> wrote:
> Conke Hu wrote:
> > Add pci class code 0x0106 for SATA to pci_ids.h
> >
> > signed-off-by: conke.hu@xxxxxxxxx
> > --------------------
> > --- linux-2.6.20-rc1/include/linux/pci_ids.h.orig     2006-12-20
> > 01:58:30.000000000 +0800
> > +++ linux-2.6.20-rc1/include/linux/pci_ids.h  2006-12-20
> > 01:59:07.000000000 +0800
> > @@ -15,6 +15,7 @@
> >  #define PCI_CLASS_STORAGE_FLOPPY     0x0102
> >  #define PCI_CLASS_STORAGE_IPI                0x0103
> >  #define PCI_CLASS_STORAGE_RAID               0x0104
> > +#define PCI_CLASS_STORAGE_SATA               0x0106
> >  #define PCI_CLASS_STORAGE_SAS                0x0107
> >  #define PCI_CLASS_STORAGE_OTHER              0x0180
>
> Two comments:
>
> 1) I think "_SATA" is an inaccurate description.  It should be _AHCI AFAICS.
>
> 2) Typically we don't add constants unless they are used somewhere...
>
>         Jeff

Hi Jeff,
   According to PCI spec 3.0, 0x0106 means SATA controller, 0x010601
means AHCI and 0x010600 means vendor specific SATA controller. Pls see
the following table (PCI spec 3.0 P296):

Base Class 	Sub-Class 	Interface 	Meaning
--------------------------------------------------------
		00h		00h 		SCSI bus controller
		------------------------------------------------
		01h 		xxh 		IDE controller
		-----------------------------------------------
		02h 		00h 		Floppy disk controller
		-----------------------------------------------------
		03h 		00h 		IPI bus controller
		--------------------------------------------------
		04h 		00h 		RAID controller
01h		------------------------------------------------
				20h 		ATA controller with ADMA interface
		05h		---------------------------------------------------
				30h 		ATA controller with ADMA interface
		-------------------------------------------------------------------
				00h 		Serial ATA controller–vendor specific interface
		06h		-----------------------------------------------------------------
		 		01h 		Serial ATA controller–AHCI 1.0 interface
		-------------------------------------------------------------------------
		07h 		00h 		Serial Attached SCSI (SAS) controller
		---------------------------------------------------------------------
		80h 		00h 		Other mass storage controller
------------------------------------------------------------------------------


So, I think, the following macro is correct:
#define PCI_CLASS_STORAGE_SATA               0x0106
If you would define AHCI class code, it should be 0x010601, not 0x0106:
#define PCI_CLASS_STORAGE_SATA_AHCI               0x010601

And, I think that PCI_CLASS_STORAGE_SATA had better be added to
pci_ids.h since the class code 0x0106 is used more than once. e.g.
ahci.c uses the magic number 0x0106 twice, and it might be used more
in future.

Best regards,
Conke
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