From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 49592E776F4 for ; Wed, 4 Oct 2023 09:11:06 +0000 (UTC) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 941C786E7C; Wed, 4 Oct 2023 11:11:03 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=andestech.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by phobos.denx.de (Postfix, from userid 109) id 23C2486E95; Wed, 4 Oct 2023 11:11:02 +0200 (CEST) Received: from Atcsqr.andestech.com (60-248-80-70.hinet-ip.hinet.net [60.248.80.70]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id BFE7286E77 for ; Wed, 4 Oct 2023 11:10:58 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=andestech.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=ycliang@andestech.com Received: from mail.andestech.com (ATCPCS16.andestech.com [10.0.1.222]) by Atcsqr.andestech.com with ESMTP id 3949AcdD009385; Wed, 4 Oct 2023 17:10:38 +0800 (+08) (envelope-from ycliang@andestech.com) Received: from swlinux02 (10.0.15.183) by ATCPCS16.andestech.com (10.0.1.222) with Microsoft SMTP Server id 14.3.498.0; Wed, 4 Oct 2023 17:10:37 +0800 Date: Wed, 4 Oct 2023 17:08:37 +0800 From: Leo Liang To: Chanho Park CC: "'Heinrich Schuchardt'" , "'Simon Glass'" , , "'Rick Chen'" Subject: Re: [PATCH v3 3/3] timer: riscv_aclint_timer: add timer_get_boot_us for BOOTSTAGE Message-ID: References: <20230906051814.1393464-1-chanho61.park@samsung.com> <20230906051814.1393464-4-chanho61.park@samsung.com> <641ab172-256a-4d38-84d8-bdf871adddd1@canonical.com> <000001d9e156$1e85e9f0$5b91bdd0$@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <000001d9e156$1e85e9f0$5b91bdd0$@samsung.com> User-Agent: Mutt/2.2.10 (e0e92c31) (2023-03-25) X-Originating-IP: [10.0.15.183] X-DNSRBL: X-MAIL: Atcsqr.andestech.com 3949AcdD009385 X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.8 at phobos.denx.de X-Virus-Status: Clean Hi On Thu, Sep 07, 2023 at 03:39:57PM +0900, Chanho Park wrote: > Hi, > > > -----Original Message----- > > From: Heinrich Schuchardt > > Sent: Thursday, September 7, 2023 2:27 AM > > To: Chanho Park ; Simon Glass > > > > Cc: u-boot@lists.denx.de; Rick Chen ; Leo > > > > Subject: Re: [PATCH v3 3/3] timer: riscv_aclint_timer: add > > timer_get_boot_us for BOOTSTAGE > > > > On 06.09.23 07:18, Chanho Park wrote: > > > timer_get_boot_us function is required to record the boot stages as > > > us-based timestamp. > > > To get a micro-second time from a timer tick, this converts the > > > formula like below to avoid zero result of (tick / rate) part. > > > > > > From: time(us) = (tick / rate) * 10000000 > Still typo 10000000 -> 1000000 > > > > Where is the old implementation that you refer to? > > I referred it from timer_get_boot_us function of lib/time.c > > lib/time.c > 55 else if (timer_rate > 1000000) > 56 return lldiv(count, timer_rate / 1000000); > 57 else > 58 return (unsigned long long)count * 1000000 / timer_rate; > > > > > > To : time(us) = (tick * 1000) / (rate / 1000) > > > > > > Signed-off-by: Chanho Park > > > --- > > > drivers/timer/riscv_aclint_timer.c | 23 +++++++++++++++++++++++ > > > 1 file changed, 23 insertions(+) > > > > > > diff --git a/drivers/timer/riscv_aclint_timer.c > > b/drivers/timer/riscv_aclint_timer.c > > > index e29d527c8d77..73fb87912851 100644 > > > --- a/drivers/timer/riscv_aclint_timer.c > > > +++ b/drivers/timer/riscv_aclint_timer.c > > > @@ -6,6 +6,7 @@ > > > > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -44,6 +45,28 @@ u64 notrace timer_early_get_count(void) > > > } > > > #endif > > > > > > +#if CONFIG_IS_ENABLED(RISCV_MMODE) && CONFIG_IS_ENABLED(BOOTSTAGE) > > > +ulong timer_get_boot_us(void) > > > +{ > > > + int ret; > > > + u64 ticks = 0; > > > + u32 rate; > > > + > > > + ret = dm_timer_init(); > > > + if (!ret) { > > > + rate = timer_get_rate(gd->timer); > > > + timer_get_count(gd->timer, &ticks); > > > + } else { > > > + rate = RISCV_MMODE_TIMER_FREQ; > > > + ticks = readq((void __iomem > > *)MTIME_REG(RISCV_MMODE_TIMERBASE, > > > + RISCV_MMODE_TIMEROFF)); > > > + } > > > + > > > + /* Below is converted from time(us) = (tick / rate) * 10000000 */ > > > + return lldiv(ticks * 1000, (rate / 1000));i Reviewed-by: Leo Yu-Chi Liang > > > > I found similar code in drivers/timer/cadence-ttc.c and > > drivers/timer/omap-timer.c with > > > > us = (ticks * 1000) / rate; > > return us. > > > > Either their code or yours must be wrong. > > > > What I am missing in include/timer.h is a documentation that defines if > > timer_dev_priv.clock_rate and timer_get_rate() yield the frequency in Hz > > or kHz. > > 'rate' seems to be Hz not kHz. So, I think they need to be corrected. > > > > > Once we have added the missing information in the include we can start > > reviewing this patch. > > > > I really dislike that we have code per architecture and don't update and > > use a implementation in lib/time.c (where we also have an > > implementation) or drivers/timer/timer-uclass.c. Can't we have a single > > implementation which is driver model based and eliminate all others? > > Actually, I tried to use lib/time.c's implementation or make a generic function in timer-uclass.c as you mentioned. > However, there are different implementations in cadence-ttc.c, rockchip_timer.c, tegra-timer.c, omap-timer.c and tsc_timer.c. > The basic codes seems to be almost identical if we can get a DM timer successfully but fallback codes look different. > If timer_get_boot_us can be implement in the timer-uclass.c, we still need per-driver callback function for supporting these different fallback codes. > I think we could merge this patch set first, and then think more thoroghly about how we are going to clean this up. Best regards, Leo > Best Regards, > Chanho Park >