Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752152Ab3F0GCq (ORCPT ); Thu, 27 Jun 2013 02:02:46 -0400 Received: from guitar.tcltek.co.il ([192.115.133.116]:43093 "EHLO sivan.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751003Ab3F0GCp (ORCPT ); Thu, 27 Jun 2013 02:02:45 -0400 Date: Thu, 27 Jun 2013 09:02:34 +0300 From: Baruch Siach To: Maxime Ripard Cc: John Stultz , Thomas Gleixner , Emilio Lopez , linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, sunny@allwinnertech.com, shuge@allwinnertech.com, kevin@allwinnertech.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 2/8] clocksource: sun4i: Add clocksource and sched clock drivers Message-ID: <20130627060234.GD4824@tarshish> References: <1372281421-2099-1-git-send-email-maxime.ripard@free-electrons.com> <1372281421-2099-3-git-send-email-maxime.ripard@free-electrons.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1372281421-2099-3-git-send-email-maxime.ripard@free-electrons.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3066 Lines: 92 Hi Maxime, On Wed, Jun 26, 2013 at 11:16:55PM +0200, Maxime Ripard wrote: > The A10 and the A13 has a 64 bits free running counter that we can use > as a clocksource and a sched clock, that were both not used yet on these > platforms. > > Signed-off-by: Maxime Ripard > --- > drivers/clocksource/sun4i_timer.c | 27 +++++++++++++++++++++++++++ > 1 file changed, 27 insertions(+) > > diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c > index bdf34d9..1d2eaa0 100644 > --- a/drivers/clocksource/sun4i_timer.c > +++ b/drivers/clocksource/sun4i_timer.c > @@ -23,6 +23,8 @@ > #include > #include > > +#include In the tip.git tree (and -next) this header is moved to in 38ff87f77a (sched_clock: Make ARM's sched_clock generic for all architectures). > + > #define TIMER_IRQ_EN_REG 0x00 > #define TIMER_IRQ_EN(val) BIT(val) > #define TIMER_IRQ_ST_REG 0x04 > @@ -34,6 +36,11 @@ > #define TIMER_CNTVAL_REG(val) (0x10 * val + 0x18) > > #define TIMER_SCAL 16 > +#define TIMER_CNT64_CTL_REG 0xa0 > +#define TIMER_CNT64_CTL_CLR BIT(0) > +#define TIMER_CNT64_CTL_RL BIT(1) > +#define TIMER_CNT64_LOW_REG 0xa4 > +#define TIMER_CNT64_HIGH_REG 0xa8 > > static void __iomem *timer_base; > > @@ -96,6 +103,20 @@ static struct irqaction sun4i_timer_irq = { > .dev_id = &sun4i_clockevent, > }; > > +static u32 sun4i_timer_sched_read(void) You commit message mentions "64 bits free running counter", but this one only returns 32 bit. baruch > +{ > + u32 reg = readl(timer_base + TIMER_CNT64_CTL_REG); > + writel(reg | TIMER_CNT64_CTL_RL, timer_base + TIMER_CNT64_CTL_REG); > + while (readl(timer_base + TIMER_CNT64_CTL_REG) & TIMER_CNT64_CTL_REG); > + > + return readl(timer_base + TIMER_CNT64_LOW_REG); > +} > + > +static cycle_t sun4i_timer_clksrc_read(struct clocksource *c) > +{ > + return sun4i_timer_sched_read(); > +} > + > static void __init sun4i_timer_init(struct device_node *node) > { > unsigned long rate = 0; > @@ -117,6 +138,12 @@ static void __init sun4i_timer_init(struct device_node *node) > > rate = clk_get_rate(clk); > > + writel(TIMER_CNT64_CTL_CLR, timer_base + TIMER_CNT64_CTL_REG); > + setup_sched_clock(sun4i_timer_sched_read, 32, clk_get_rate(clk)); > + clocksource_mmio_init(timer_base + TIMER_CNT64_LOW_REG, node->name, > + clk_get_rate(clk), 300, 32, > + sun4i_timer_clksrc_read); > + > writel(rate / (TIMER_SCAL * HZ), > timer_base + TIMER_INTVAL_REG(0)); > -- http://baruch.siach.name/blog/ ~. .~ Tk Open Systems =}------------------------------------------------ooO--U--Ooo------------{= - baruch@tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il - -- 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/