From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomeu Vizoso Subject: Re: [PATCH v3 04/13] of: document new emc-timings subnode in nvidia,tegra124-car Date: Fri, 07 Nov 2014 14:03:51 +0100 Message-ID: <545CC337.4020409@collabora.com> References: <1414599796-30597-1-git-send-email-tomeu.vizoso@collabora.com> <1414599796-30597-5-git-send-email-tomeu.vizoso@collabora.com> <545B172C.4060105@nvidia.com> <545C5927.3010001@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <545C5927.3010001-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alexandre Courbot , Rob Herring Cc: "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Javier Martinez Canillas , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Stephen Warren , Thierry Reding , Alexandre Courbot , Peter De Schrijver , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: devicetree@vger.kernel.org On 11/07/2014 06:31 AM, Alexandre Courbot wrote: > On 11/07/2014 12:12 AM, Rob Herring wrote: >> On Thu, Nov 6, 2014 at 12:37 AM, Alexandre Courbot wrote: >>> On 10/30/2014 01:22 AM, Tomeu Vizoso wrote: >>>> >>>> The EMC clock needs some extra information for changing its rate. >>>> >>>> Signed-off-by: Tomeu Vizoso >>>> --- >>>> .../bindings/clock/nvidia,tegra124-car.txt | 46 >>>> +++++++++++++++++++++- >>>> 1 file changed, 44 insertions(+), 2 deletions(-) >>>> >>>> diff --git >>>> a/Documentation/devicetree/bindings/clock/nvidia,tegra124-car.txt >>>> b/Documentation/devicetree/bindings/clock/nvidia,tegra124-car.txt >>>> index ded5d62..42e0588 100644 >>>> --- a/Documentation/devicetree/bindings/clock/nvidia,tegra124-car.txt >>>> +++ b/Documentation/devicetree/bindings/clock/nvidia,tegra124-car.txt >>>> @@ -19,12 +19,35 @@ Required properties : >>>> In clock consumers, this cell represents the bit number in the CAR's >>>> array of CLK_RST_CONTROLLER_RST_DEVICES_* registers. >>>> >>>> +The node should contain a "emc-timings" subnode for each supported RAM >>>> type (see >>>> +field RAM_CODE in register PMC_STRAPPING_OPT_A), with its unit address >>>> being its >>>> +RAM_CODE. >>>> + >>>> +Required properties for "emc-timings" nodes : >>>> +- nvidia,ram-code : Should contain the value of RAM_CODE this timing set >>>> + is used for. >>>> + >>>> +Each "emc-timings" node should contain a "timing" subnode for every >>>> supported >>>> +EMC clock rate. The "timing" subnodes should have the clock rate in Hz as >>>> their >>>> +unit address. >>> >>> >>> This seems to be a quite liberal use of unit addresses (same in the next >>> patch) - is this allowed by DT? >> >> No, unit address should match a reg property. > > Mmm, would you have any suggestion as to how this can be fixed? Right > now what I can think of is either to replace the "clock-frequency" > property by "reg" (which would be confusing), or to use a different > naming scheme, e.g. timing-12750000. IIUC the naming is not essential > for properly parsing these nodes, so maybe the second solution is the > way to go? Yeah, there seems to be a precedent for embedding the frequency in the node name in the TI DTs, e.g.: virt_12000000_ck. Thanks, Tomeu