dmaengine: driver for the ARM PL080/PL081 PrimeCells v5

This creates a DMAengine driver for the ARM PL080/PL081 PrimeCells
based on the implementation earlier submitted by Peter Pearse.
This is working like a charm for memcpy and slave DMA to the PL011
PrimeCell on the PB11MPCore.

This DMA controller is used in mostly unmodified form in the ARM
RealView and Versatile platforms, in the ST-Ericsson Nomadik, and
in the ST SPEAr platform.

It has been converted to use the header from the Samsung PL080
derivate instead of its own defintions. The Samsungs have a custom
driver in their mach-* folders though, atleast we can share the
register definitions.

Cc: Peter Pearse <peter.pearse@arm.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Alessandro Rubini <rubini@unipv.it>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
[GFP_KERNEL to GFP_NOWAIT in pl08x_prep_dma_memcpy]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/Kconfig

@@ -49,6 +49,14 @@ config INTEL_MID_DMAC
 config ASYNC_TX_DISABLE_CHANNEL_SWITCH
 	bool
 
+config AMBA_PL08X
+	bool "ARM PrimeCell PL080 or PL081 support"
+	depends on ARM_AMBA && EXPERIMENTAL
+	select DMA_ENGINE
+	help
+	  Platform has a PL08x DMAC device
+	  which can provide DMA engine support
+
 config INTEL_IOATDMA
 	tristate "Intel I/OAT DMA support"
 	depends on PCI && X86

drivers/dma/Makefile

@@ -25,3 +25,4 @@ obj-$(CONFIG_TIMB_DMA) += timb_dma.o
 obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
 obj-$(CONFIG_PL330_DMA) += pl330.o
 obj-$(CONFIG_PCH_DMA) += pch_dma.o
+obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o