From patchwork Wed Jan 30 13:16:00 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steffen Trumtrar X-Patchwork-Id: 216903 Return-Path: X-Original-To: incoming-imx@patchwork.ozlabs.org Delivered-To: patchwork-incoming-imx@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 52E6B2C0150 for ; Thu, 31 Jan 2013 00:19:35 +1100 (EST) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1U0XXB-0001ri-5t; Wed, 30 Jan 2013 13:17:01 +0000 Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1U0XX6-0001pN-SP for linux-arm-kernel@lists.infradead.org; Wed, 30 Jan 2013 13:16:57 +0000 Received: from dude.hi.pengutronix.de ([2001:6f8:1178:2:21e:67ff:fe11:9c5c]) by metis.ext.pengutronix.de with esmtp (Exim 4.72) (envelope-from ) id 1U0XX1-0000WK-V3; Wed, 30 Jan 2013 14:16:51 +0100 Received: from str by dude.hi.pengutronix.de with local (Exim 4.80) (envelope-from ) id 1U0XX1-0003Jv-Ti; Wed, 30 Jan 2013 14:16:51 +0100 From: Steffen Trumtrar To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2] ARM i.MX25: clk: parent per5_clk to AHB clock Date: Wed, 30 Jan 2013 14:16:00 +0100 Message-Id: <1359551760-28862-1-git-send-email-s.trumtrar@pengutronix.de> X-Mailer: git-send-email 1.7.10.4 X-SA-Exim-Connect-IP: 2001:6f8:1178:2:21e:67ff:fe11:9c5c X-SA-Exim-Mail-From: str@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130130_081657_093598_23A2660F X-CRM114-Status: GOOD ( 13.97 ) X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Steffen Trumtrar , Russell King , stable@vger.kernel.org, Sascha Hauer X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org List-Id: linux-imx-kernel.lists.patchwork.ozlabs.org The mxc-timer on the imx25 needs to be derived from the AHB clock. If a bootloader reparents this clock to the ipg_clk_highfreq, which according to the datasheet is a valid operation, the system can/will produce lockups/ freezes after some time [1]. This can be forced with code like while(1) syscall(SYS_clock_gettime, CLOCK_REALTIME, &tp); This was already fixed with the commit "i.MX25 GPT clock fix: ensure correct the clock source" [2], for 3.1-rc2, but was lost, when i.MX was converted to the common clock framework ("ARM i.MX25: implement clocks using common clock framework") [3] [1]: http://lists.arm.linux.org.uk/lurker/message/20130129.161230.229bda17.en.html [2]: 2012d9ca2a1381ae3e733330a7f0d1d2f1988bba [3]: 6bbaec5676e4f475b0d78743cbd4c70a8804ce14 Signed-off-by: Steffen Trumtrar Cc: stable@vger.kernel.org # v3.5+ --- arch/arm/mach-imx/clk-imx25.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/mach-imx/clk-imx25.c b/arch/arm/mach-imx/clk-imx25.c index 5d34f67..0e6dde6 100644 --- a/arch/arm/mach-imx/clk-imx25.c +++ b/arch/arm/mach-imx/clk-imx25.c @@ -177,6 +177,9 @@ static int __init __mx25_clocks_init(unsigned long osc_rate) pr_err("i.MX25 clk %d: register failed with %ld\n", i, PTR_ERR(clk[i])); + /* Clock source for gpt must be derived from AHB */ + clk_set_parent(clk[per5_sel], clk[ahb]); + clk_register_clkdev(clk[ipg], "ipg", "imx-gpt.0"); clk_register_clkdev(clk[gpt_ipg_per], "per", "imx-gpt.0");