Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754924AbcJZI4M (ORCPT ); Wed, 26 Oct 2016 04:56:12 -0400 Received: from foss.arm.com ([217.140.101.70]:34216 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752976AbcJZI4G (ORCPT ); Wed, 26 Oct 2016 04:56:06 -0400 From: Brian Starkey To: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Subject: [RFC PATCH v2 2/9] drm: mali-dp: Clear CVAL when leaving config mode Date: Wed, 26 Oct 2016 09:55:01 +0100 Message-Id: <1477472108-27222-3-git-send-email-brian.starkey@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1477472108-27222-1-git-send-email-brian.starkey@arm.com> References: <1477472108-27222-1-git-send-email-brian.starkey@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1410 Lines: 35 It's possible for CVAL to get set whilst we are in config mode. If this happens, afer we leave config mode the HW will latch whatever configuration is in the registers at the next vsync. Most likely this will be a partial configuration, as we'll be racing against the ongoing atomic_commit. To avoid this, clear CVAL before leaving config mode. Signed-off-by: Brian Starkey --- drivers/gpu/drm/arm/malidp_hw.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/arm/malidp_hw.c b/drivers/gpu/drm/arm/malidp_hw.c index 7f4a0bd..65e667b 100644 --- a/drivers/gpu/drm/arm/malidp_hw.c +++ b/drivers/gpu/drm/arm/malidp_hw.c @@ -125,6 +125,7 @@ static void malidp500_leave_config_mode(struct malidp_hw_device *hwdev) { u32 status, count = 100; + malidp_hw_clearbits(hwdev, MALIDP_CFG_VALID, MALIDP500_CONFIG_VALID); malidp_hw_clearbits(hwdev, MALIDP500_DC_CONFIG_REQ, MALIDP500_DC_CONTROL); while (count) { status = malidp_hw_read(hwdev, hwdev->map.dc_base + MALIDP_REG_STATUS); @@ -271,6 +272,7 @@ static void malidp550_leave_config_mode(struct malidp_hw_device *hwdev) { u32 status, count = 100; + malidp_hw_clearbits(hwdev, MALIDP_CFG_VALID, MALIDP550_CONFIG_VALID); malidp_hw_clearbits(hwdev, MALIDP550_DC_CONFIG_REQ, MALIDP550_DC_CONTROL); while (count) { status = malidp_hw_read(hwdev, hwdev->map.dc_base + MALIDP_REG_STATUS); -- 1.7.9.5