Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966221AbaFRLbQ (ORCPT ); Wed, 18 Jun 2014 07:31:16 -0400 Received: from mail-pd0-f181.google.com ([209.85.192.181]:44590 "EHLO mail-pd0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933182AbaFRLbO (ORCPT ); Wed, 18 Jun 2014 07:31:14 -0400 From: Amit Daniel Kachhap To: linux-samsung-soc@vger.kernel.org, Kukjin Kim , Daniel Lezcano , Thomas Gleixner Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, David Riley , Doug Anderson , Tomasz Figa Subject: [PATCH] clocksource: exynos-mct: Register the timer for stable udelay Date: Wed, 18 Jun 2014 17:01:00 +0530 Message-Id: <1403091060-5054-1-git-send-email-amit.daniel@samsung.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch register the exynos mct clocksource as the current timer as it has constant clock rate. This will generate correct udelay for the exynos platform and avoid using unnecessary calibrated jiffies. This change have been tested on exynos5420 based board. Signed-off-by: Amit Daniel Kachhap --- Patches from David Riley confirmed that udelay is broken in exynos5420. Link to those patches are, 1) https://patchwork.kernel.org/patch/4344911/ 2) https://patchwork.kernel.org/patch/4344881/ drivers/clocksource/exynos_mct.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c index 8d64200..57cb3dc 100644 --- a/drivers/clocksource/exynos_mct.c +++ b/drivers/clocksource/exynos_mct.c @@ -198,10 +198,21 @@ static u64 notrace exynos4_read_sched_clock(void) return exynos4_frc_read(&mct_frc); } +static struct delay_timer exynos4_delay_timer; + +static unsigned long exynos4_read_current_timer(void) +{ + return exynos4_frc_read(&mct_frc); +} + static void __init exynos4_clocksource_init(void) { exynos4_mct_frc_start(0, 0); + exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer; + exynos4_delay_timer.freq = clk_rate; + register_current_timer_delay(&exynos4_delay_timer); + if (clocksource_register_hz(&mct_frc, clk_rate)) panic("%s: can't register clocksource\n", mct_frc.name); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/