From patchwork Tue May 13 09:15:26 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun Kumar K X-Patchwork-Id: 4163841 Return-Path: X-Original-To: patchwork-linux-samsung-soc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 42ABBBFF02 for ; Tue, 13 May 2014 09:15:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 65FE420340 for ; Tue, 13 May 2014 09:15:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22F9920155 for ; Tue, 13 May 2014 09:15:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759949AbaEMJPi (ORCPT ); Tue, 13 May 2014 05:15:38 -0400 Received: from mail-pb0-f49.google.com ([209.85.160.49]:43651 "EHLO mail-pb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759947AbaEMJPg (ORCPT ); Tue, 13 May 2014 05:15:36 -0400 Received: by mail-pb0-f49.google.com with SMTP id jt11so49601pbb.36 for ; Tue, 13 May 2014 02:15:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id; bh=MO5cOTYHb8n0ck5nwiB4qVhqUW+krePxNjTpmTx5LMc=; b=AK+3mGUkagUzZfDM7PiyPiQeX4ujvvrQk5rtDvPDiClLK7NzCWNioz1vK2qssRZBW6 vpoWkTi1yAlYcvBnrjYIY68a5X1IkdWi4CuzSkpN/OzazLSTFtnh8CYF2DS5JVII82Ov KOXqLNs0CaNCLQzyY/1aN8tQh1U0lrZCa7wsYJtEDeRLbF6Er3YCQ8Mj5Q250PD6xwo/ RKI0Am3MQ4sa7ikSKaBVVsytmeRmcD4zNggPD4QoLaVVJO7jSwF81Lj0DQBwoOcV5LFA Ew+S8yAlIZ43OMZGHEz+0qDHitu/FPzRZ1tKhQgV4rPLq0Ye5wP9InMT8PkP2NAaOLRg Bx0Q== X-Received: by 10.66.156.34 with SMTP id wb2mr55404244pab.83.1399972535868; Tue, 13 May 2014 02:15:35 -0700 (PDT) Received: from localhost.localdomain ([14.140.216.146]) by mx.google.com with ESMTPSA id sv10sm27102260pbc.74.2014.05.13.02.15.32 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 13 May 2014 02:15:35 -0700 (PDT) From: Arun Kumar K To: linux-samsung-soc@vger.kernel.org Cc: kgene.kim@samsung.com, t.figa@samsung.com, tomasz.figa@gmail.com, tushar.behera@linaro.org, shaik.ameer@samsung.com Subject: [PATCH] ARM: dts: Remove g2d_pd node for exynos5420 Date: Tue, 13 May 2014 14:45:26 +0530 Message-Id: <1399972526-20828-1-git-send-email-arun.kk@samsung.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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>; }; };