linux/drivers/dma/dw
Serge Semin ca7f285171 dmaengine: dw: Introduce max burst length hw config
IP core of the DW DMA controller may be synthesized with different
max burst length of the transfers per each channel. According to Synopsis
having the fixed maximum burst transactions length may provide some
performance gain. At the same time setting up the source and destination
multi size exceeding the max burst length limitation may cause a serious
problems. In our case the DMA transaction just hangs up. In order to fix
this lets introduce the max burst length platform config of the DW DMA
controller device and don't let the DMA channels configuration code
exceed the burst length hardware limitation.

Note the maximum burst length parameter can be detected either in runtime
from the DWC parameter registers or from the dedicated DT property.
Depending on the IP core configuration the maximum value can vary from
channel to channel so by overriding the channel slave max_burst capability
we make sure a DMA consumer will get the channel-specific max burst
length.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-27 14:30:55 +05:30
..
acpi.c dmaengine: dw: Register ACPI DMA controller for PCI that has companion 2020-06-16 21:54:47 +05:30
core.c dmaengine: dw: Introduce max burst length hw config 2020-07-27 14:30:55 +05:30
dw.c dmaengine: dw: Don't pollute CTL_LO on iDMA 32-bit 2019-01-07 17:57:13 +05:30
idma32.c dmaengine: dw: Don't pollute CTL_LO on iDMA 32-bit 2019-01-07 17:57:13 +05:30
internal.h dmaengine: dw: platform: Split OF helpers to separate module 2019-08-21 09:41:28 +05:30
Kconfig dmaengine: dw: convert to SPDX identifiers 2019-01-07 17:57:13 +05:30
Makefile dmaengine: dw: Replace 'objs' by 'y' 2020-06-16 21:54:47 +05:30
of.c dmaengine: dw: Introduce max burst length hw config 2020-07-27 14:30:55 +05:30
pci.c dmaengine: dw: Register ACPI DMA controller for PCI that has companion 2020-06-16 21:54:47 +05:30
platform.c dmaengine: dw: platform: Mark 'hclk' clock optional 2019-10-14 13:51:44 +05:30
regs.h dmaengine: dw: Introduce max burst length hw config 2020-07-27 14:30:55 +05:30