Re: [PATCH v2 3/3] ARM: shmobile: gose: Add QSPI device to DT

[Simon Horman <horms@verge.net.au>]

On Thu, Nov 12, 2015 at 11:44:15AM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Thu, Nov 12, 2015 at 2:29 AM, Simon Horman
> <horms+renesas@verge.net.au> wrote:
> > Enable the QSPI controller in the gose device tree.
> >
> > Based similar work for the silk board by by Vladimir Barinov and
> > Sergei Shtylyov.
> >
> > Cc: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
> > Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> 
> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
> 
> > ---
> > Tested: Read /dev/mtd0 with 512K blocks at 1.7MB/s
> 
> That's slow: I get 6.7 MB/s on koelsch (69.9 Mbps for Quad Read according
> to my in-kernel QSPI debug code). Is this with SYS-DMAC enabled?

Yes it does seem very small.

I think that the problem is that /dev/mtd0 is very small, only 262kB.
And I do not see any interrupts for dma-controllers when reading from hit.

/dev/mdt1 is much later, 4.2MB.
dd reads that at ~7MB/s using 512kB blocks.
In that test I see interrupts for one of the dma-controllers.

I plan to go ahead and apply this series.