Re: [PATCH 1/2] sata_promise: issue ATAPI commands as normal packets

[Jeff Garzik <jeff@garzik.org>]

Mikael Pettersson wrote:
> This patch (against libata #upstream + the ATAPI cleanup patch)
> reimplements sata_promise's ATAPI support to format ATAPI DMA
> commands as normal packets, and to issue them via the hardware's
> normal packet machinery.
> 
> It turns out that the only reason for issuing ATAPI DMA
> commands via the pdc_issue_atapi_pkt_cmd() procedure was to
> perform two interrupt-fiddling steps for ATA_DFLAG_CDB_INTR
> devices. But these steps aren't needed because sata_promise
> sets ATA_FLAG_PIO_POLLING, which disables DMA for those devices.
> The remaining steps can easily be done in ATA taskfile packets.
> 
> Concrete changes:
> - pdc_atapi_dma_pkt() is extended to program all packet setup
>   steps, and not just contain the CDB; the sequence of steps
>   exactly mirrors what pdc_issue_atapi_pkt_cmd() did
> - pdc_atapi_dma_pkt() needed more parameters: simplify it by
>   just passing 'qc' and having it extract the data it needs
> - pdc_issue_atai_pkt_cmd() and its two helper procedures
>   pdc_wait_for_drq() and pdc_wait_on_busy() are removed
> 
> Tested on first- and second-generation chips, SATAPI and PATAPI,
> with no observable regressions.
> 
> Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>

Applied patches 1-2.

ATAPI handling looks _so_ much better, now that you're using packets, 
doesn't it?  :)

	Jeff