Re: [PATCH] PCI: keystone: add a pci quirk to limit mrrs

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

 



On 08/06/2014 12:58 PM, Jason Gunthorpe wrote:
On Wed, Aug 06, 2014 at 12:56:04PM -0400, Murali Karicheri wrote:
On 08/06/2014 12:30 PM, Jason Gunthorpe wrote:
On Wed, Aug 06, 2014 at 11:18:20AM -0400, Murali Karicheri wrote:
Keystone PCI controller has a limitation that memory read request
size must not exceed 256 bytes. This is a hardware limitation and
add a quirk to force this limit on all downstream devices by
updating mrrs.

Does this still work if the tuning is enabled, or does the tuning run
after this?

Yes it works with tuning enabled. Tuning happens afterwards. The
'limiting mrrs to 256' below is from my patch.

That seems backwards to me...
Rational? The tuning is reading mrrs and set mps to less than or equal to mrss. So adding this before make sure mrrs used is below keystones's limit.

Murali

Jason

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




[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux