Re: [PATCH v3 35/77] ncr5380: Dont wait for BUS FREE after disconnect

Hannes Reinecke
2015-12-22T07:31:11Z

On 12/22/2015 02:18 AM, Finn Thain wrote:
> When there is a queued command and no connected command, NCR5380_select()
> is called and arbitration begins. The chip waits for BUS FREE once the
> MR_ARBITRATE bit in the mode register is enabled. That means there is
> no need to wait for BUS FREE after disconnecting.
>
> There is presently no polling for BUS FREE after sending an ABORT or
> other message that might lead to disconnection. It only happens after
> COMMAND COMPLETE or DISCONNECT messages, which seems inconsistent.
> Remove the polling for !BSY in the COMMAND COMPLETE and DISCONNECT
> cases.
>
> BTW, the comments say "avoid nasty timeouts" and perhaps BUS FREE polling
> was somehow helpful back in Linux v0.99.14u, when it was introduced.
> The relevant timeout is presently 1 second (for bus arbitration).
>
> Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
>
> ---
> drivers/scsi/NCR5380.c | 7 -------
> drivers/scsi/atari_NCR5380.c | 11 -----------
> 2 files changed, 18 deletions(-)
>
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
--
Dr. Hannes Reinecke zSeries & Storage
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