treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dmaengine: pxa: use a dma slave map

In order to remove the specific knowledge of the dma mapping from PXA
drivers, add a default slave map for pxa architectures.

This won't impact MMP architecture, but is aimed only at all PXA boards.

This is the first step, and once all drivers are converted,
pxad_filter_fn() will be made static, and the DMA resources removed from
device.c.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vinod Koul <vkoul@kernel.org>

dmaengine: mmp-pdma: add number of requestors

The DMA chip has a fixed number of requestor lines used for flow
control. This number is platform dependent. The pxa_dma dma driver will
use this value to activate or not the flow control.

There won't be any impact on mmp_pdma driver.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>

dmaengine: mmp-pdma support

1. virtual channel vs. physical channel
Virtual channel is managed by dmaengine
Physical channel handling resource, such as irq
Physical channel is alloced dynamically as descending priority,
freed immediately when irq done.
The availble highest priority physically channel will alwayes be alloced

Issue pending list -> alloc highest dma physically channel available -> dma done -> free physically channel

2. list: running list & pending list
submit: desc list -> pending list
issue_pending_list: if (IDLE) pending list -> running list; free pending list (RUN)
irq: free running list (IDLE)
check pendlist -> pending list -> running list; free pending list (RUN)

3. irq:
Each list generate one irq, calling callback
One list may contain several desc chain, in such case, make sure only the last desc list generate irq.

4. async
Submit will add desc chain to pending list, which can be multi-called
If multi desc chain is submitted, only the last desc would generate irq -> call back
If IDLE, issue_pending_list start pending_list, transforming pendlist to running list
If RUN, irq will start pending list

5. test
5.1 pxa3xx_nand on pxa910
5.2 insmod dmatest.ko (threads_per_chan=y)
By default drivers/dma/dmatest.c test every channel and test memcpy with 1 threads per channel

Signed-off-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>