Re: [PATCH v2 08/11] ARM: dts: zynq: Add VDMA to Parallella

Andreas Färber
2014-07-25T09:47:13Z

Hi Sören,

Am 25.07.2014 01:22, schrieb Sören Brinkmann:
> 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-parallella.dts | 25 +++++++++++++++++++++++++
>> 1 file changed, 25 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/zynq-parallella.dts b/arch/arm/boot/dts/zynq-parallella.dts
>> index e60a0a9..8beaacc 100644
>> --- a/arch/arm/boot/dts/zynq-parallella.dts
>> +++ b/arch/arm/boot/dts/zynq-parallella.dts
>> @@ -32,6 +32,31 @@
>> bootargs = "console=ttyPS0,115200 earlyprintk root=/dev/mmcblk0p2 rootfstype=ext4 rw rootwait";
>> linux,stdout-path = "/amba/serial@e0001000";
>> };
>> +
>> + fpga {
> Do you really want FPGA components in this DT?
> If somebody tries booting with this DT without programming with a
> corresponding bitstream, the whole system might hang.
> Just something to consider.

Well, that's related to a question that remained unanswered on v1:
whether we may need to turn this into a .dtsi to cope with variations.

The Parallella has an on-board µHDMI connector, and two bitstreams are
delivered - one for HDMI and one for headless usage. In my testing I am
using the original HDMI bitstream but serial console for lack of
upstream HDMI drivers. Do you think we need to provide
zynq-parallella-hdmi.dts and zynq-parallella-headless.dts? (It gets
worse if at some point we need to handle variations of the on-board
Epiphany chip plus the bitstreams - at least the Z7010 vs. Z7020 doesn't
affect DT AFAICT.)

Since, as noted in the cover letter, these FPGA patches are not yet
fully testable, I wouldn't mind deferring them, but wanted to get them
out for review early.

http://www.parallella.org/2014/07/14/new-parallella-product-offerings/
indicates there will be a new variation in gen2 without USB/HDMI. Would
it be valid to #include a .dts (rather than .dtsi) to override status
and keep number of Parallella files low?

Regards,
Andreas

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