From patchwork Tue Apr 12 10:42:55 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Grygorii Strashko X-Patchwork-Id: 8809371 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 [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0DF979F54F for ; Tue, 12 Apr 2016 10:45:32 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5929D2035D for ; Tue, 12 Apr 2016 10:45:27 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5F1CE2035B for ; Tue, 12 Apr 2016 10:45:21 +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 1apvnF-0004rt-02; Tue, 12 Apr 2016 10:43:37 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1apvnB-0004qE-7z for linux-arm-kernel@lists.infradead.org; Tue, 12 Apr 2016 10:43:34 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id u3CAh1L3009953; Tue, 12 Apr 2016 05:43:01 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id u3CAh0Yi028146; Tue, 12 Apr 2016 05:43:00 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.3.224.2; Tue, 12 Apr 2016 05:43:00 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id u3CAgx2J011429; Tue, 12 Apr 2016 05:43:00 -0500 From: Grygorii Strashko To: Subject: [PATCH] ARM: omap2: am437x: rollback to use omap3_gptimer_timer_init() Date: Tue, 12 Apr 2016 13:42:55 +0300 Message-ID: <1460457775-23850-1-git-send-email-grygorii.strashko@ti.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160412_034333_397158_2979BB44 X-CRM114-Status: UNSURE ( 9.92 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -7.9 (-------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Felipe Balbi , Grygorii Strashko , Lokesh Vutla , nsekhar@ti.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 The commit 55ee7017ee31 ("arm: omap2: board-generic: use omap4_local_timer_init for AM437x") unintentionally changes the clocksource devices for AM437x from OMAP GP Timer to SyncTimer32K. Unfortunately, the SyncTimer32K is starving from frequency deviation as mentioned in commit 5b5c01359152 ("ARM: OMAP2+: AM43x: Use gptimer as clocksource") and, as reported by Franklin [1], even its monotonic nature is under question (most probably there is a HW issue, but it's still under investigation). Taking into account above facts It's reasonable to rollback to the use of omap3_gptimer_timer_init(). [1] http://www.spinics.net/lists/linux-omap/msg127425.html Cc: Felipe Balbi Cc: Lokesh Vutla Reported-by: Cooper Jr., Franklin Signed-off-by: Grygorii Strashko Tested-by: Franklin S Cooper Jr. --- arch/arm/mach-omap2/board-generic.c | 2 +- arch/arm/mach-omap2/timer.c | 7 +++++-- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c index bab814d..60f5e83 100644 --- a/arch/arm/mach-omap2/board-generic.c +++ b/arch/arm/mach-omap2/board-generic.c @@ -306,7 +306,7 @@ DT_MACHINE_START(AM43_DT, "Generic AM43 (Flattened Device Tree)") .init_late = am43xx_init_late, .init_irq = omap_gic_of_init, .init_machine = omap_generic_init, - .init_time = omap4_local_timer_init, + .init_time = omap3_gptimer_timer_init, .dt_compat = am43_boards_compat, .restart = omap44xx_restart, MACHINE_END diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index 6261e93..7cc055c 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -500,16 +500,19 @@ void __init omap3_secure_sync32k_timer_init(void) } #endif /* CONFIG_ARCH_OMAP3 */ -#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) +#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \ + defined(CONFIG_SOC_AM43XX) void __init omap3_gptimer_timer_init(void) { __omap_sync32k_timer_init(2, "timer_sys_ck", NULL, 1, "timer_sys_ck", "ti,timer-alwon", true); + if (of_have_populated_dt()) + clocksource_probe(); } #endif #if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) || \ - defined(CONFIG_SOC_DRA7XX) || defined(CONFIG_SOC_AM43XX) + defined(CONFIG_SOC_DRA7XX) static void __init omap4_sync32k_timer_init(void) { __omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",