From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [REPOST PATCH 1/4] ARM: dts: DRA7: Add dsp1_system syscon node Date: Mon, 12 Oct 2015 15:50:02 -0700 Message-ID: <20151012225001.GK23801@atomide.com> References: <1443828205-18706-1-git-send-email-s-anna@ti.com> <1443828205-18706-2-git-send-email-s-anna@ti.com> <20151012214304.GD23801@atomide.com> <561C351B.3060307@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <561C351B.3060307-l0cyMroinI0@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Suman Anna Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org * Suman Anna [151012 15:37]: > Hi Tony, > > On 10/12/2015 04:43 PM, Tony Lindgren wrote: > > * Suman Anna [151002 16:27]: > >> The DSP_SYSTEM sub-module is a dedicated system control logic > >> module present within a DRA7 DSP processor sub-system. This > >> module is responsible for power management, clock generation > >> and connection to the device PRCM module. > >> > >> Add a syscon node for this module for the DSP1 processor > >> sub-system. This is added as a syscon node as it is a common > >> configuration module that can be used by the different IOMMU > >> instances and the corresponding remoteproc device. > >> > >> The node is added to the common dra7.dtsi file, as the DSP1 > >> processor sub-system is mostly common across all the variants > >> of the DRA7 SoC family. > >> > >> Signed-off-by: Suman Anna > >> --- > >> arch/arm/boot/dts/dra7.dtsi | 5 +++++ > >> 1 file changed, 5 insertions(+) > >> > >> diff --git a/arch/arm/boot/dts/dra7.dtsi b/arch/arm/boot/dts/dra7.dtsi > >> index e289c706d27d..62055094e8d5 100644 > >> --- a/arch/arm/boot/dts/dra7.dtsi > >> +++ b/arch/arm/boot/dts/dra7.dtsi > >> @@ -292,6 +292,11 @@ > >> #thermal-sensor-cells = <1>; > >> }; > >> > >> + dsp1_system: dsp_system@40d00000 { > >> + compatible = "syscon"; > >> + reg = <0x40d00000 0x100>; > >> + }; > >> + > >> sdma: dma-controller@4a056000 { > >> compatible = "ti,omap4430-sdma"; > >> reg = <0x4a056000 0x1000>; > > > > Hmm so why would you want to set up a complete device as a syscon > > mapping rather than just doing ioremap on it? > > > > What drivers will be sharing access to these registers? > > Two different instances of the MMU for now, both get probed > independently. But there are other registers which a remoteproc driver > will mostly be interested in (like DSP_SYS_STAT for knowing the C66x > idle/active status). OK makes sense to me then. Thanks, Tony