From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Lechner Subject: Re: [PATCH] ARM: dts: da850-evm: add clock properties to the nand node Date: Tue, 6 Feb 2018 12:16:48 -0600 Message-ID: <794024f3-f87a-58ed-2722-a4a2d09df3ce@lechnology.com> References: <20180205155222.22189-1-brgl@bgdev.pl> <3f171f6a-bcea-65ec-d56d-f6ae24660f34@ti.com> <54dbdb98-e0e4-c8c9-fec4-2f050745d9be@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <54dbdb98-e0e4-c8c9-fec4-2f050745d9be-l0cyMroinI0@public.gmane.org> Content-Language: en-US Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sekhar Nori , Bartosz Golaszewski Cc: Bartosz Golaszewski , Kevin Hilman , Rob Herring , Mark Rutland , Russell King , arm-soc , linux-devicetree , LKML List-Id: devicetree@vger.kernel.org On 02/06/2018 07:51 AM, Sekhar Nori wrote: > On Tuesday 06 February 2018 06:38 PM, Bartosz Golaszewski wrote: >> 2018-02-06 12:07 GMT+01:00 Sekhar Nori : >>> On Monday 05 February 2018 09:22 PM, Bartosz Golaszewski wrote: >>>> From: Bartosz Golaszewski >>>> >>>> Make nand work with the common clock framework by specifying which >>>> clock should be used and what name to look up. >>>> >>>> Signed-off-by: Bartosz Golaszewski >>>> --- >>>> arch/arm/boot/dts/da850-evm.dts | 3 +++ >>>> 1 file changed, 3 insertions(+) >>>> >>>> diff --git a/arch/arm/boot/dts/da850-evm.dts b/arch/arm/boot/dts/da850-evm.dts >>>> index a86a8a1816f2..2602ad8e99ee 100644 >>>> --- a/arch/arm/boot/dts/da850-evm.dts >>>> +++ b/arch/arm/boot/dts/da850-evm.dts >>>> @@ -296,6 +296,9 @@ >>>> reg = <0 0x02000000 0x02000000 >>>> 1 0x00000000 0x00008000>; >>>> >>>> + clocks = <&psc0 3>; >>>> + clock-names = "aemif"; >>> >>> Looks like this is being added only to satisfy the devm_clk_get() call >>> in nand_davinci_probe() which I think is superfluous since we also >>> enable the same clock in aemif_probe(). >>> >>> Perhaps the better solution is to drip the clk code in >>> drivers/mtd/nand/davinci_nand.c and shift legacy code to start using >>> drivers/memory/aemif.c as well? This way we can also drop >>> arch/arm/mach-davinci/aemif.c >>> >>> Thanks, >>> Sekhar >> >> Yes, this sounds good, but I think we should leave it for later as an >> additional improvement, once everything else is in place. I think >> these patches should be applied together with David's series in order >> to not break the support on davinci boards and the aemif work would go >> in later as a follow-up. How about that? > > No, I dont think we should add temporary hacks to DT to work around > driver issues (I do think its a hack since the clock belongs to aemif > module not NAND flash). > > An easier driver hack might be to not treat devm_clk_get() failure in > davinci_nand.c as catastrophic. It will safely fail in DT case and we > should get the clock in legacy boot case. > > I think we are looking at a driver update dependency anyway. It looks like keystone.dtsi is using the clock-ranges property in the aemif node to pass the clock to child nodes. Could we not do the same in da850.dtsi? > >> >> Also: I don't have any keystone board to test whether such changes >> don't break the nand support there. Would you be able to test this? > > Yes, I have access to those boards. > > Thanks, > Sekhar > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html