From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: Re: [PATCH 2/7] dt-bindings: add binding for the Allwinner A64 DE2 bus Date: Mon, 26 Mar 2018 17:22:58 -0500 Message-ID: <20180326222258.uxpgj4bk4pg56b7o@rob-hp-laptop> References: <20180316175354.21437-1-icenowy@aosc.io> <20180320184646.dynqv6qubzabroe4@flea> <2866474.lRHIcLtROC@jernej-laptop> <9520BDDE-BFE3-4220-B48D-01A00CFA94DE@aosc.io> Reply-To: robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Content-Disposition: inline In-Reply-To: <9520BDDE-BFE3-4220-B48D-01A00CFA94DE-h8G6r0blFSE@public.gmane.org> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Icenowy Zheng Cc: jernej.skrabec-gGgVlfcn5nU@public.gmane.org, linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Maxime Ripard , Chen-Yu Tsai , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On Thu, Mar 22, 2018 at 02:08:43PM +0800, Icenowy Zheng wrote: >=20 >=20 > =E4=BA=8E 2018=E5=B9=B43=E6=9C=8822=E6=97=A5 GMT+08:00 =E4=B8=8A=E5=8D=88= 1:13:42, "Jernej =C5=A0krabec" =E5=86=99=E5=88=B0= : > >Hi all, > > > >Dne sreda, 21. marec 2018 ob 03:18:13 CET je Icenowy Zheng napisal(a): > >> =E4=BA=8E 2018=E5=B9=B43=E6=9C=8821=E6=97=A5 GMT+08:00 =E4=B8=8A=E5=8D= =882:46:46, Maxime Ripard > >=20 > >=E5=86=99=E5=88=B0: > >> >On Sat, Mar 17, 2018 at 01:53:49AM +0800, Icenowy Zheng wrote: > >> >> All the sub-blocks of Allwinner A64 DE2 needs the SRAM C on A64 > >SoC > >> > > >> >to > >> > > >> >> be claimed, otherwise the whole DE2 space is inaccessible. > >> >>=20 > >> >> Add a device tree binding of the DE2 part as a sub-bus. > >> > > >> >Where did you get the info that it was a bus? > >>=20 > >> There's no direct evidence, just some guess. > >>=20 > >> The DE2 is a whole part that is just allocated a memory > >> space at the user manual, and the SRAM controls the > >> access to all modules in the DE2. > >>=20 > >> So it might be a bus. > >>=20 > >> Implement it as a bus is a clear representation on A64. > > > >Since there is already syscon for same mmio region, we migh as well use > >it=20 > >when loading ccu-sun8i-de2 driver on A64. > > > >Other options, like SRAM driver or bus driver, might better represent > >HW, but=20 >=20 > I think the device tree should properly represent the HW, > it's a basic requirment. >=20 > >then we would have two DT nodes covering same mmio region, which I > >think is=20 > >not really acceptable. >=20 > It's acceptable, and DE2 is not the only user of SRAM controller so far. No, it's not acceptable. Don't create overlapping mmio regions in DT. >=20 > VE will also need a SRAM region to be claimed. >=20 > > > >Any suggestions? > > > >BTW, H6 has same design in this regard. > > > >Best regards, > >Jernej > -- > 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 --=20 You received this message because you are subscribed to the Google Groups "= linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to linux-sunxi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit https://groups.google.com/d/optout.