Re: [PATCH 2.6.20-rc3] sata_promise: ATAPI support

From: Mikael Pettersson
Date: Mon Jan 08 2007 - 03:55:54 EST


On Sun, 07 Jan 2007 20:50:48 -0500, Jeff Garzik wrote:
> > With this patch ATAPI will work on SATA ports on second-generation
> > chips, and on the first-generation PATA-only 20619. ATAPI on the
> > 2057x' PATA port will work automatically when #promise-sata-pata
> > is updated. ATAPI on the 2037x' PATA port is enabled by a followup
> > patch for the #promise-sata-pata branch.
> >
> > Signed-off-by: Mikael Pettersson <mikpe@xxxxxxxx>
>
> No objections, minor revision requests follow.
>
> * general comment: please combine the 'make first gen SATAPI work'
> patch with this one.

Will do.

> > +static unsigned int pdc_wait_for_drq(struct ata_port *ap)
> > +{
> > + void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
> > + unsigned int i;
> > + unsigned int status;
> > +
> > + /* Following pdc-ultra's WaitForDrq() we loop here until BSY
> > + * is clear and DRQ is set in altstatus. We could possibly call
> > + * ata_busy_wait() and loop until DRQ is set, but since we don't
> > + * know how much time a call to ata_busy_wait() took, we don't
> > + * know when to time out the outer loop.
> > + */
> > + for(i = 0; i < 1000; ++i) {
> > + status = readb(port_mmio + 0x38); /* altstatus */
> > + if (status == 0xFF)
> > + break;
> > + if (status & ATA_BUSY)
> > + ;
> > + else if (status & (ATA_DRQ | ATA_ERR))
> > + break;
> > + mdelay(1);
> > + }
>
> This really hurts to do this with spinlocks held. Long term, ponder
> ways to move this to a kernel thread that can sleep [if it takes too long?]

On the TODO list for a later update.

> > +static void pdc_issue_atapi_pkt_cmd(struct ata_queued_cmd *qc)
> > +{
> > + struct ata_port *ap = qc->ap;
> > + void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
> > + void __iomem *host_mmio = ap->host->mmio_base;
> > + unsigned int nbytes;
> > + unsigned int tmp;
> > +
> > + /* disable INTA here, it will be re-enable when CAM use SEQ 0 for packets */
>
> cut-n-pasted comment? This is not CAM :)

Indeed :-) Will fix.

> > + writeb(0x00, port_mmio + PDC_CTLSTAT); /* that the drive INT pass to SEQ 0*/
> > + writeb(0x20, host_mmio + 0); /* but mask SEQ 0 INT */
>
> please create named constants for these magic numbers

Will do (for this and the other places you pointed out).

/Mikael
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