Re: [PATCH] dmaengine: nbpfaxi: add optional max-burst property for memory reads/writes

[Rob Herring]

On Mon, Oct 24, 2016 at 03:29:15PM +0200, Niklas Cassel wrote:
> From: Niklas Cassel <niklas.cassel@xxxxxxxx>
> 
> Due to a hardware bug, reading memory (from the Accelerator Coherency Port)
> with a burst size equal to the maximum burst size allowed by the DMA
> hardware's buffer size will cause a hardware hang on the ARTPEC-6 SoC,
> where the only solution is a manual power cycle.
> On ARTPEC-6, this hardware bug does not trigger when writing memory (to the
> Accelerator Coherency Port) with a burst size equal to the maximum burst
> size allowed by the DMA hardware's buffer size.
> 
> To avoid this hardware hang, introduce a new optional max-burst property
> for memory reads. For completeness, also introduce a max-burst property for
> memory writes.
> 
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
> ---
>  Documentation/devicetree/bindings/dma/nbpfaxi.txt |  8 +++++
>  drivers/dma/nbpfaxi.c                             | 38 ++++++++++++++++++++---
>  2 files changed, 42 insertions(+), 4 deletions(-)

Acked-by: Rob Herring <robh@xxxxxxxxxx>