From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kukjin Kim Subject: Re: [PATCH] ARM: dts: Remove g2d_pd node for exynos5420 Date: Thu, 15 May 2014 04:09:11 +0900 Message-ID: <5373BF57.6040109@samsung.com> References: <1399972526-20828-1-git-send-email-arun.kk@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f50.google.com ([209.85.160.50]:50410 "EHLO mail-pb0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750906AbaENTJR (ORCPT ); Wed, 14 May 2014 15:09:17 -0400 Received: by mail-pb0-f50.google.com with SMTP id ma3so2058049pbc.9 for ; Wed, 14 May 2014 12:09:16 -0700 (PDT) In-Reply-To: <1399972526-20828-1-git-send-email-arun.kk@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Arun Kumar K Cc: linux-samsung-soc@vger.kernel.org, kgene.kim@samsung.com, t.figa@samsung.com, tomasz.figa@gmail.com, tushar.behera@linaro.org, shaik.ameer@samsung.com On 05/13/14 18:15, Arun Kumar K wrote: > G2D power domain also controls the CMU block of G2D. > Since clock registers can be accessed anytime for viewing > clk_summary, it can cause a system crash if g2d power domain > is disabled. > > Signed-off-by: Arun Kumar K > --- > Please also refer to the existing discussion on removal of > mau_pd node. > http://comments.gmane.org/gmane.linux.kernel.samsung-soc/29718 > > This patch also fixes a similar issue of the power domian being > linked to the CMU block. AFAIK, only MAU and G2D power domains > has this problem in 5420. > > The issue is more critical now with the merging of following > patches in Tomasz's clk tree - > clk: samsung exynos5250/5420: Add gate clock for SSS module > clk: exynos5420: update clocks for G2D and G3D blocks > > With these patches, I get the following crash on kernel booting - > [8.971209] Unhandled fault: imprecise external abort (0x1406) at 0x00000000 > [8.993044] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000007 > > For fixing this, either g2d_pd has to be removed or we need to make all > GATE clocks touching the GATE_IP_G2D as CLK_IGNORE_UNUSED. > I believe removing g2d_pd is the better solution as we get almost the > same power saving by gating off these clocks and keeping the domain ON. > --- > arch/arm/boot/dts/exynos5420.dtsi | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi > index 2f6da50..47d3f17 100644 > --- a/arch/arm/boot/dts/exynos5420.dtsi > +++ b/arch/arm/boot/dts/exynos5420.dtsi > @@ -242,11 +242,6 @@ > reg =<0x100440E0 0x20>; > }; > > - g2d_pd: power-domain@10044100 { > - compatible = "samsung,exynos4210-pd"; > - reg =<0x10044100 0x20>; > - }; > - > msc_pd: power-domain@10044120 { > compatible = "samsung,exynos4210-pd"; > reg =<0x10044120 0x20>; > @@ -755,6 +750,5 @@ > interrupts =<0 112 0>; > clocks =<&clock 471>; > clock-names = "secss"; > - samsung,power-domain =<&g2d_pd>; > }; > }; OK, applied. Thanks, Kukjin