From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932211AbdDPU2v (ORCPT ); Sun, 16 Apr 2017 16:28:51 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:36331 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756974AbdDPU2b (ORCPT ); Sun, 16 Apr 2017 16:28:31 -0400 From: Daniel Lezcano To: tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, Russell King Subject: [PATCH 20/29] clocksource/drivers/orion: Add delay_timer implementation Date: Sun, 16 Apr 2017 22:27:10 +0200 Message-Id: <1492374441-23336-20-git-send-email-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1492374441-23336-1-git-send-email-daniel.lezcano@linaro.org> References: <20170416202542.GV2078@mai> <1492374441-23336-1-git-send-email-daniel.lezcano@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Russell King Add an implementation for the ARM delay timer, which is used for udelay(). This provides less CPU dependent and more accurate delays - the CPU loop on Marvell Dove appears to calibrate to around 6% too short. Signed-off-by: Russell King Signed-off-by: Daniel Lezcano --- drivers/clocksource/time-orion.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c index c4818a5..7eb2ab0 100644 --- a/drivers/clocksource/time-orion.c +++ b/drivers/clocksource/time-orion.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -36,6 +37,21 @@ static void __iomem *timer_base; +static unsigned long notrace orion_read_timer(void) +{ + return ~readl(timer_base + TIMER0_VAL); +} + +static struct delay_timer orion_delay_timer = { + .read_current_timer = orion_read_timer, +}; + +static void orion_delay_timer_init(unsigned long rate) +{ + orion_delay_timer.freq = rate; + register_current_timer_delay(&orion_delay_timer); +} + /* * Free-running clocksource handling. */ @@ -168,6 +184,9 @@ static int __init orion_timer_init(struct device_node *np) clockevents_config_and_register(&orion_clkevt, rate, ORION_ONESHOT_MIN, ORION_ONESHOT_MAX); + + orion_delay_timer_init(rate); + return 0; } CLOCKSOURCE_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init); -- 2.7.4