From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yingjoe Chen Subject: Re: [PATCH 1/5] soc: mediatek: Add SMI driver Date: Tue, 10 Mar 2015 14:17:22 +0800 Message-ID: <1425968242.4871.136.camel@mtksdaap41> References: <1425638900-24989-1-git-send-email-yong.wu@mediatek.com> <1425638900-24989-2-git-send-email-yong.wu@mediatek.com> <1425641445.24292.280.camel@x220> <1425902271.13300.18.camel@mhfsdcap03> <1425923977.2317.4.camel@tiscali.nl> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1425923977.2317.4.camel-IWqWACnzNjzz+pZb47iToQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Paul Bolle Cc: Yong Wu , Mark Rutland , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, srv_heupstream-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, Catalin Marinas , Joerg Roedel , Will Deacon , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Tomasz Figa , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Rob Herring , Daniel Kurtz , Sasha Hauer , Matthias Brugger , linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Robin Murphy , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Lucas Stach List-Id: devicetree@vger.kernel.org On Mon, 2015-03-09 at 18:59 +0100, Paul Bolle wrote: > Hi Yong, > > Yong Wu schreef op ma 09-03-2015 om 19:57 [+0800]: > > On Fri, 2015-03-06 at 12:30 +0100, Paul Bolle wrote: > > > On Fri, 2015-03-06 at 18:48 +0800, yong.wu-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org wrote: > > > > --- a/drivers/soc/mediatek/Kconfig > > > > +++ b/drivers/soc/mediatek/Kconfig > > > > @@ -20,3 +20,10 @@ config MT8173_PMIC_WRAP > > > > PMIC wrapper is a proprietary hardware in MT8173 to make > > > > communication protocols to access PMIC device. > > > > This driver implement access protocols for MT8173. > > > > + > > > > +config MTK_SMI > > > > + bool > > > > > > Nit: make this one tab instead of 8 spaces, please. > > > > > > > + help > > > > + Smi help enable/disable iommu in mt8173 and control the > > > > + clock of each local arbiter. > > > > + It should be true while MTK_IOMMU enable. > > > > > > I don't think anyone using the *config tools will ever see this text, as > > > there's no prompt. So you might as well make this a comment or drop it > > > altogether. > > > > > We could search it in the tool even though we don't see it. In next > > version, I will try to make it a comment. > > > Is this selected by more than just MTK_IOMMU (see 2/5)? If not, I think > > > MTK_SMI will be set and unset in lockstep with MTK_IOMMU. In other > > > words, you could as well use one Kconfig symbol. > > > > > if we disable MTK_IOMMU, the MTK_SMI also should be selected.That is because > > if the multimedia h/w want to work, the clock of the local arbiters always should be opened. > > This is a bit confusing, I'm afraid. Do you mean to say that it ought to > be possible for MTK_SMI to be 'y' even if MTK_IOMMU would be 'n'? The SMI can be configured to bypass IOMMU and send traffic directly to memory interface. It is possible to not use IOMMU and have display/MM to use continuous memory only. Besides MTK_IOMMU, we expect DRM, VDEC driver to select MTK_SMI as well. Joe.C -- 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