From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752196Ab0GYRLh (ORCPT ); Sun, 25 Jul 2010 13:11:37 -0400 Received: from filtteri5.pp.htv.fi ([213.243.153.188]:40778 "EHLO filtteri5.pp.htv.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751942Ab0GYRLK (ORCPT ); Sun, 25 Jul 2010 13:11:10 -0400 From: Alexander Shishkin To: linux-arm-kernel@lists.infradead.org Cc: Alexander Shishkin , Russell King , linux-kernel@vger.kernel.org Subject: [PATCH 4/7] etm: do a dummy read from OSSRR during initialization Date: Sun, 25 Jul 2010 20:05:17 +0300 Message-Id: <1280077520-7538-5-git-send-email-virtuoso@slind.org> X-Mailer: git-send-email 1.7.1 In-Reply-To: <13B9B4C6EF24D648824FF11BE896716203BADA0745@dlee02.ent.ti.com> References: <13B9B4C6EF24D648824FF11BE896716203BADA0745@dlee02.ent.ti.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The first read from ETM OS save and restore register after the power down bit deassertion returns garbage. Signed-off-by: Alexander Shishkin Cc: Russell King Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org --- arch/arm/kernel/etm.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c index d08062b..73b824a 100644 --- a/arch/arm/kernel/etm.c +++ b/arch/arm/kernel/etm.c @@ -558,7 +558,9 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id) t->etm_portsz = 1; etm_unlock(t); - ret = etm_readl(t, ETMMR_PDSR); + (void)etm_readl(t, ETMMR_PDSR); + /* dummy first read */ + (void)etm_readl(&tracer, ETMMR_OSSRR); t->ncmppairs = etm_readl(t, ETMR_CONFCODE) & 0xf; etm_writel(t, 0x440, ETMR_CTRL); -- 1.7.1