When the manager is running non-secure, the only channels that can
issue interrupts are the ones that have a 1 in their corresponding bit
in Configuration Register 3. The other ones will generate an abort
when trying to signal the end of the transaction so they are useless
in non-secure mode.

Reference: <1320244259-10496-2-git-send-email-javi.merino@arm.com>
Signed-off-by: NJavi Merino <javi.merino@arm.com>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

If two requests have been submitted and one of them is running, if you
call pl330_chan_ctrl(ch_id, PL330_OP_START), there's a window of time
between the spin_lock_irqsave() and the _state() check in which the
running transaction may finish.  In that case, we don't receive the
interrupt (because they are disabled), but _start() sees that the DMA
is stopped, so it starts it.  The problem is that it sends the
transaction that has just finished again, because pl330_update()
hasn't mark it as done yet.

This patch fixes this race condition by not calling _start() if the
DMA is already executing transactions.  When interrupts are reenabled,
pl330_update() will call _start().

Reference: <1317892206-3600-1-git-send-email-javi.merino@arm.com>
Signed-off-by: NJavi Merino <javi.merino@arm.com>
Acked-by: NJassi Brar <jassi.brar@samsung.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

The driver can handle different revisions of the core
which vary only minorly.
Signed-off-by: NJassi Brar <jassi.brar@samsung.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

PL330 is a configurable DMA controller PrimeCell device.
The register map of the device is well defined.
The configuration of a particular implementation can be
read from the six configuration registers CR0-4,Dn.

This patch implements a driver for the specification:-
http://infocenter.arm.com/help/topic/com.arm.doc.ddi0424a/DDI0424A_dmac_pl330_r0p0_trm.pdf

The exported interface should be sufficient to implement
a driver for any DMA API.
Signed-off-by: NJassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>