From mboxrd@z Thu Jan 1 00:00:00 1970 From: virtuoso@slind.org Subject: [PATCH 3/6] etm: do a dummy read from OSSRR during initialization Date: Sat, 1 May 2010 20:38:18 +0300 Message-ID: <1272735501-2963-4-git-send-email-virtuoso@slind.org> References: <1272735501-2963-1-git-send-email-virtuoso@slind.org> Return-path: Received: from smtp.nokia.com ([192.100.105.134]:44762 "EHLO mgw-mx09.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751501Ab0EARlR (ORCPT ); Sat, 1 May 2010 13:41:17 -0400 In-Reply-To: <1272735501-2963-1-git-send-email-virtuoso@slind.org> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: tony@atomide.com Cc: linux-omap@vger.kernel.org, khilman@deeprootsystems.com, r-woodruff2@ti.com, Alexander Shishkin From: Alexander Shishkin The first read from ETM OS save and restore register after the power down bit deassertion returns garbage. Signed-off-by: Alexander Shishkin --- 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); -- 1.7.1.1.g15764