Re: [PATCH 1/3] Make the IDE DMA timeout modifiable

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Sergei Shtylyov wrote:
Mark Lord wrote:

O> >> BTW, why the timeout is so damn long? 2*WAIT_CMD is 20 secs, and if DMA is not complete or interrupt pending, it may wait 10 more secs...
..
I've lost the original question from this thread, but the idea of the

The original question concerned specifically the DMA command timeout which is twice more than the usual one, WAIT_CMD (10 seconds).

longish
timeouts was that drive *may* be spun down ("standby"), and thus have to spin up again to complete media commands. Back then, drives were much slower at spinning up than nowadays, and the ATA spec says to allow up to 30 seconds.

   Well, that doesn't explain the DMA case.

When a drive is in standby, we don't send it anything special to wake up.
So even DMA commands have to have a long enough timeout to allow
for spinning up.

Cheers
-
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Filesystems]     [Linux SCSI]     [Linux RAID]     [Git]     [Kernel Newbies]     [Linux Newbie]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Samba]     [Device Mapper]

  Powered by Linux