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    SubjectRe: [PATCH v2 06/11] ARM: dts: zynq: Add DMAC for Parallella
    On Fri, 2014-07-25 at 10:24AM +0200, Andreas Färber wrote:
    > Am 25.07.2014 10:02, schrieb Michal Simek:
    > > On 07/25/2014 01:28 AM, Sören Brinkmann wrote:
    > >> On Fri, 2014-07-25 at 01:00AM +0200, Andreas Färber wrote:
    > >>> Signed-off-by: Andreas Färber <afaerber@suse.de>
    > >>> ---
    > >>> v2: New
    > >>>
    > >>> arch/arm/boot/dts/zynq-7000.dtsi | 17 +++++++++++++++++
    > >>> arch/arm/boot/dts/zynq-parallella.dts | 4 ++++
    > >>> 2 files changed, 21 insertions(+)
    > >>>
    > >>> diff --git a/arch/arm/boot/dts/zynq-7000.dtsi b/arch/arm/boot/dts/zynq-7000.dtsi
    > >>> index eed3df0..1a70277 100644
    > >>> --- a/arch/arm/boot/dts/zynq-7000.dtsi
    > >>> +++ b/arch/arm/boot/dts/zynq-7000.dtsi
    > >>> @@ -223,6 +223,23 @@
    > >>> };
    > >>> };
    > >>>
    > >>> + dmac_s: dmac@f8003000 {
    > >>> + compatible = "arm,pl330", "arm,primecell";
    > >>> + reg = <0xf8003000 0x1000>;
    > >>> + status = "disabled";
    > >> I think for this IP we can omit the 'status' property since it is always
    > >> enabled. I don't see a reason to override it in each board DT.
    > >
    > > Done this change myself
    >
    > Fine with me, but allow me to point out that the TRM documents the DMAC
    > being mapped as DMAC S at the above address, and as DMAC NS at F800_4000
    > (secure vs. non-secure, ch. 4.6, p. 116). Not sure how this would be
    > handled driver-wise if not through alternative dt nodes?

    The upstream Linux runs in secure state on Zynq, hence I think this is fine. If
    somebody wants to run Linux on Zynq non-secure they have to do some work
    anyhow. This way the standard configuration can use the DMA engine.

    Sören

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