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path: root/drivers/rapidio/devices/tsi721_dma.c
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2014-07-30rapidio/tsi721_dma: fix failure to obtain transaction descriptorAlexandre Bounine
This is a bug fix for the situation when function tsi721_desc_get() fails to obtain a free transaction descriptor. The bug usually results in a memory access crash dump when data transfer scatter-gather list has more entries than size of hardware buffer descriptors ring. This fix ensures that error is properly returned to a caller instead of an invalid entry. This patch is applicable to kernel versions starting from v3.5. 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> Cc: <stable@vger.kernel.org> [3.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07drivers/rapidio/devices/tsi721_dma.c: optimize use of BDMA descriptorsAlexandre Bounine
Combine SG entries describing single contiguous memory block into one Tsi721 BDMA descriptor. This reduces number of hardware descriptors required for large data transfers and improves performance on the PCIe side by reducing number of descriptor fetch requests. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-04rapidio/tsi721: fix tasklet termination in dma channel releaseAlexandre Bounine
This patch is a modification of the patch originally proposed by Xiaotian Feng <xtfeng@gmail.com>: https://lkml.org/lkml/2012/11/5/413 This new version disables DMA channel interrupts and ensures that the tasklet wil not be scheduled again before calling tasklet_kill(). Unfortunately the updated patch was not released at that time due to planned rework of Tsi721 mport driver to use threaded interrupts (which has yet to happen). Recently the issue was reported again: https://lkml.org/lkml/2014/2/19/762. Description from the original Xiaotian's patch: "Some drivers use tasklet_disable in device remove/release process, tasklet_disable will inc tasklet->count and return. If the tasklet is not handled yet under some softirq pressure, the tasklet will be placed on the tasklet_vec, never have a chance to be excuted. This might lead to a heavy loaded ksoftirqd, wakeup with pending_softirq, but tasklet is disabled. tasklet_kill should be used in this case." This patch is applicable to kernel versions starting from v3.5. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Xiaotian Feng <xtfeng@gmail.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <bitbucket@online.de> Cc: <stable@vger.kernel.org> [3.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-28rapidio: remove use of __devinitBill Pemberton
CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: Matt Porter <mporter@kernel.crashing.org> Acked-by: Alexandre Bounine <alexandre.bounine@idt.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-31rapidio/tsi721: add DMA engine supportAlexandre Bounine
Adds support for DMA Engine API into Tsi721 mport driver. Includes following changes for Tsi721 driver: - Modifies BDMA register offset definitions to support per-channel handling - Separates BDMA channel reserved for RIO Maintenance requests - Adds DMA Engine callback routines Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Li Yang <leoli@freescale.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>