[RFC PATCH] edac: zynq: Added EDAC support for zynq ddr ecc controller

[Sören Brinkmann]

On Tue, 2014-03-11 at 09:32AM +0100, Michal Simek wrote:
> On 03/10/2014 11:32 PM, Sören Brinkmann wrote:
> > On Mon, 2014-03-10 at 12:58PM +0100, Michal Simek wrote:
> >> On 03/10/2014 11:56 AM, Mark Rutland wrote:
> >>> On Sun, Mar 09, 2014 at 02:57:16AM +0000, Punnaiah Choudary Kalluri wrote:
> >>>> Added EDAC support for reporting the ecc errors of zynq ddr controller.
> >>>> The ddr ecc controller corrects single bit errors and detects double bit
> >>>> errors
> >>>>
> >>>> Signed-off-by: Punnaiah Choudary Kalluri <punnaia at xilinx.com>
> >>>> ---
> >>>>  .../devicetree/bindings/edac/zynq_edac.txt         |   18 +
> >>>>  drivers/edac/Kconfig                               |    7 +
> >>>>  drivers/edac/Makefile                              |    1 +
> >>>>  drivers/edac/zynq_edac.c                           |  613 ++++++++++++++++++++
> >>>>  4 files changed, 639 insertions(+), 0 deletions(-)
> >>>>  create mode 100644 Documentation/devicetree/bindings/edac/zynq_edac.txt
> >>>>  create mode 100644 drivers/edac/zynq_edac.c
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/edac/zynq_edac.txt b/Documentation/devicetree/bindings/edac/zynq_edac.txt
> >>>> new file mode 100644
> >>>> index 0000000..c21ff83
> >>>> --- /dev/null
> >>>> +++ b/Documentation/devicetree/bindings/edac/zynq_edac.txt
> >>>> @@ -0,0 +1,18 @@
> >>>> +Zynq EDAC driver, it does reports the DDR ECC single bit errors that are
> >>>> +corrected and double bit ecc errors that are detected by the DDR ECC controller.
> >>>> +ECC support for DDR is available in half-bus width(16 bit) configuration only.
> >>>> +
> >>>> +Required properties:
> >>>> +- compatible: Should be "xlnx,ps7-ddrc" or "xlnx,ps7-ddrc-1.00.a"
> >>>
> >>> Is this an or or a xor?
> >>
> >> Compatible string should be just xlnx,zynq-ddrc-1.00.a.
> >> Nothing with ps7.
> > 
> > Isn't this vendor IP? IMHO, this should be something completely
> > different. Or if you want some Zynq-specific compat string it should
> > refer to an actual version string associated with Zynq. 1.00.a is not,
> > AFAIK.
> 
> I have checked with Punnaiah that this is Synopsys DDR memory controller.
> Zynq is based on 1.4 version with some customization.
> It means I think reasonable solution is
> call it drivers/edac/synopsys_edac.c
> rename zynq_ in driver to synopsys_ and
> use xlnx,zynq-ddrc-1.00.a compatible string because zynq is not using
> clean synopsys version.
> 
> I am not getting point why you don't like 1.00.a suffix here.
> Because of historical point of view compatible strings should be different
> for early silicon, silicon v1, silicon v2, silicon v3, etc
> but we haven't used it at all that's why we can use xilinx scheme
> which we are using for our soft IPs.

Well, but you refer to Zynq which has silicon revisions you can use to
refer to a specific Zynq version. That matches data sheets. Zynq-1.00.a
is just completely made up and wouldn't be found in any data sheet.

	Sören