linux/drivers/rapidio
Alexandre Bounine 50835e977b rapidio/tsi721_dma: rework scatter-gather list handling
Rework Tsi721 RapidIO DMA engine support to allow handling data
scatter/gather lists longer than number of hardware buffer descriptors in
the DMA channel's descriptor list.

The current implementation of Tsi721 DMA transfers requires that number of
entries in a scatter/gather list provided by a caller of
dmaengine_prep_rio_sg() should not exceed number of allocated hardware
buffer descriptors.

This patch removes the limitation by processing long scatter/gather lists
by sections that can be transferred using hardware descriptor ring of
configured size.  It also introduces a module parameter
"dma_desc_per_channel" to allow run-time configuration of Tsi721 hardware
buffer descriptor rings.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Stef van Os <stef.van.os@prodrive-technologies.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:24 -07:00
..
devices rapidio/tsi721_dma: rework scatter-gather list handling 2014-08-08 15:57:24 -07:00
switches Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2013-07-13 14:52:21 -07:00
Kconfig rapidio: convert switch drivers to modules 2013-07-03 16:08:04 -07:00
Makefile rapidio: add modular build option for the subsystem core 2013-07-03 16:08:05 -07:00
rio-access.c
rio-driver.c rapidio: rework device hierarchy and introduce mport class of devices 2014-04-07 16:36:07 -07:00
rio-scan.c rapidio: rework device hierarchy and introduce mport class of devices 2014-04-07 16:36:07 -07:00
rio-sysfs.c rapidio: rework device hierarchy and introduce mport class of devices 2014-04-07 16:36:07 -07:00
rio.c rapidio: add new RapidIO DMA interface routines 2014-08-08 15:57:24 -07:00
rio.h rapidio: rework device hierarchy and introduce mport class of devices 2014-04-07 16:36:07 -07:00