From patchwork Tue May 13 14:39:26 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Santosh Shilimkar X-Patchwork-Id: 4168281 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 77F029F334 for ; Tue, 13 May 2014 14:43:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 876B32020E for ; Tue, 13 May 2014 14:43:53 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AED6F20145 for ; Tue, 13 May 2014 14:43:52 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WkDs5-0004TR-0g; Tue, 13 May 2014 14:39:57 +0000 Received: from bear.ext.ti.com ([192.94.94.41]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WkDs2-0004S6-0F for linux-arm-kernel@lists.infradead.org; Tue, 13 May 2014 14:39:54 +0000 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id s4DEdV89009060; Tue, 13 May 2014 09:39:31 -0500 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id s4DEdUQn019360; Tue, 13 May 2014 09:39:30 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.174.1; Tue, 13 May 2014 09:39:30 -0500 Received: from ula0393909.am.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id s4DEdTBf017834; Tue, 13 May 2014 09:39:29 -0500 From: Santosh Shilimkar To: , Subject: [PATCH] ARM: OMAP4: Fix the boot regression with CPU_IDLE enabled Date: Tue, 13 May 2014 10:39:26 -0400 Message-ID: <1399991966-14582-1-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140513_073954_128535_78F43B0C X-CRM114-Status: GOOD ( 12.63 ) X-Spam-Score: -5.7 (-----) Cc: linux-omap@vger.kernel.org, Santosh Shilimkar , Daniel Lezcano , linux-arm-kernel@lists.infradead.org, Roger Quadros X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable 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 On OMAP4 panda board, there have been several bug reports about boot hang and lock-ups with CPU_IDLE enabled. The root cause of the issue is missing interrupts while in idle state. Commit cb7094e8 {cpuidle / omap4 : use CPUIDLE_FLAG_TIMER_STOP flag} moved the broadcast notifiers to common code for right reasons but on OMAP4 which suffers from a nasty ROM code bug with GIC, commit ff999b8a {ARM: OMAP4460: Workaround for ROM bug ..}, we loose interrupts which leads to issues like lock-up, hangs etc. Patch reverts commit cb7094 {cpuidle / omap4 : use CPUIDLE_FLAG_TIMER_STOP flag} to avoid the issue. With this change, OMAP4 panda boards, the mentioned issues are getting fixed. We no longer loose interrupts which was the cause of the regression. Cc: Roger Quadros Cc: Kevin Hilman Cc: Tony Lindgren Cc: Daniel Lezcano Reported-tested-by: Roger Quadros Reported-tested-by: Kevin Hilman Tested-by: Tony Lindgren Signed-off-by: Santosh Shilimkar --- arch/arm/mach-omap2/cpuidle44xx.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c index 01fc710..3e169d9 100644 --- a/arch/arm/mach-omap2/cpuidle44xx.c +++ b/arch/arm/mach-omap2/cpuidle44xx.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -83,6 +84,7 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, { struct idle_statedata *cx = state_ptr + index; u32 mpuss_can_lose_context = 0; + int cpu_id = smp_processor_id(); /* * CPU0 has to wait and stay ON until CPU1 is OFF state. @@ -110,6 +112,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, mpuss_can_lose_context = (cx->mpu_state == PWRDM_POWER_RET) && (cx->mpu_logic_state == PWRDM_POWER_OFF); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu_id); + /* * Call idle CPU PM enter notifier chain so that * VFP and per CPU interrupt context is saved. @@ -165,6 +169,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, if (dev->cpu == 0 && mpuss_can_lose_context) cpu_cluster_pm_exit(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu_id); + fail: cpuidle_coupled_parallel_barrier(dev, &abort_barrier); cpu_done[dev->cpu] = false; @@ -189,8 +195,7 @@ static struct cpuidle_driver omap4_idle_driver = { /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */ .exit_latency = 328 + 440, .target_residency = 960, - .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED | - CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED, .enter = omap_enter_idle_coupled, .name = "C2", .desc = "CPUx OFF, MPUSS CSWR", @@ -199,8 +204,7 @@ static struct cpuidle_driver omap4_idle_driver = { /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */ .exit_latency = 460 + 518, .target_residency = 1100, - .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED | - CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED, .enter = omap_enter_idle_coupled, .name = "C3", .desc = "CPUx OFF, MPUSS OSWR",