From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 141D570 for ; Mon, 2 Aug 2021 00:39:47 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B99E1D6E; Sun, 1 Aug 2021 17:39:46 -0700 (PDT) Received: from slackpad.fritz.box (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BE9D03F66F; Sun, 1 Aug 2021 17:39:44 -0700 (PDT) Date: Mon, 2 Aug 2021 01:39:02 +0100 From: Andre Przywara To: Jernej =?UTF-8?B?xaBrcmFiZWM=?= Cc: Maxime Ripard , Chen-Yu Tsai , Rob Herring , Icenowy Zheng , Samuel Holland , linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org, Ondrej Jirman , Alessandro Zummo , Alexandre Belloni , linux-rtc@vger.kernel.org Subject: Re: [PATCH v8 05/11] rtc: sun6i: Add support for broken-down alarm registers Message-ID: <20210802013902.7164876f@slackpad.fritz.box> In-Reply-To: <35374855.gLGPhMbAMS@kista> References: <20210723153838.6785-1-andre.przywara@arm.com> <20210723153838.6785-6-andre.przywara@arm.com> <35374855.gLGPhMbAMS@kista> Organization: Arm Ltd. X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.31; x86_64-slackware-linux-gnu) Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Sun, 25 Jul 2021 08:11:49 +0200 Jernej =C5=A0krabec wrote: Hi Jernej, > Dne petek, 23. julij 2021 ob 17:38:32 CEST je Andre Przywara napisal(a): > > Newer versions of the Allwinner RTC, for instance as found in the H616 > > SoC, not only store the current day as a linear number, but also change > > the way the alarm is handled: There are now two registers, that > > explicitly store the wakeup time, in the same format as the current > > time. > >=20 > > Add support for that variant by writing the requested wakeup time > > directly into the registers, instead of programming the seconds left, as > > the old SoCs required. > >=20 > > Signed-off-by: Andre Przywara > > --- > > drivers/rtc/rtc-sun6i.c | 60 +++++++++++++++++++++++++++++------------ > > 1 file changed, 43 insertions(+), 17 deletions(-) > >=20 > > diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c > > index a02be8bca6f3..f0ee20bfdccb 100644 > > --- a/drivers/rtc/rtc-sun6i.c > > +++ b/drivers/rtc/rtc-sun6i.c > > @@ -48,7 +48,8 @@ > > =20 > > /* Alarm 0 (counter) */ > > #define SUN6I_ALRM_COUNTER 0x0020 > > -#define SUN6I_ALRM_CUR_VAL 0x0024 > > +/* This holds the remaining alarm seconds on older SoCs (current value= ) */ > > +#define SUN6I_ALRM_COUNTER_HMS 0x0024 > > #define SUN6I_ALRM_EN 0x0028 > > #define SUN6I_ALRM_EN_CNT_EN BIT(0) > > #define SUN6I_ALRM_IRQ_EN 0x002c > > @@ -523,32 +524,57 @@ static int sun6i_rtc_setalarm(struct device *dev,= =20 > struct rtc_wkalrm *wkalrm) > > struct sun6i_rtc_dev *chip =3D dev_get_drvdata(dev); > > struct rtc_time *alrm_tm =3D &wkalrm->time; > > struct rtc_time tm_now; > > - time64_t time_now, time_set; > > + time64_t time_set; > > + u32 counter_val, counter_val_hms; > > int ret; > > =20 > > - ret =3D sun6i_rtc_gettime(dev, &tm_now); > > - if (ret < 0) { > > - dev_err(dev, "Error in getting time\n"); > > - return -EINVAL; > > - } > > - > > time_set =3D rtc_tm_to_time64(alrm_tm); > > - time_now =3D rtc_tm_to_time64(&tm_now); > > - if (time_set <=3D time_now) { > > - dev_err(dev, "Date to set in the past\n"); > > - return -EINVAL; > > - } > > =20 > > - if ((time_set - time_now) > U32_MAX) { > > - dev_err(dev, "Date too far in the future\n"); > > - return -EINVAL; > > + if (chip->flags & RTC_LINEAR_DAY) { > > + time64_t seconds; > > + > > + /* > > + * The alarm registers hold the actual alarm time, =20 > encoded > > + * in the same way (linear day + HMS) as the current =20 > time. > > + */ > > + counter_val_hms =3D SUN6I_TIME_SET_SEC_VALUE(alrm_tm- > >tm_sec) | > > + =20 > SUN6I_TIME_SET_MIN_VALUE(alrm_tm->tm_min) | > > + =20 > SUN6I_TIME_SET_HOUR_VALUE(alrm_tm->tm_hour); > > + seconds =3D mktime64(alrm_tm->tm_year + 1900, alrm_tm- > >tm_mon, > > + alrm_tm->tm_mday, 0, 0, 0); =20 >=20 > While above line should work, it's confusing why you're adding 1900 to ye= ars.=20 > In my opinion it would be better to use same trick you used in patch 4 -= =20 > rtc_tm_to_time64() with hours, minutes and seconds set to 0. IIRC setalarm does not want the time struct to be changed, but this is OK in settime. But anyway ... > Or maybe you=20 > don't even need to do that, since division by SECS_PER_DAY will round dow= n=20 > anyway. In such way you hide RTC internal representation detail which doe= sn't=20 > need to be exposed here. That is indeed a very clever idea! I changed both settime and setalarm accordingly now, adding a comment about this. >=20 > Once fixed: > Reviewed by: Jernej Skrabec Many thanks for the reviews! Cheers, Andre > > + counter_val =3D div_u64(seconds, SECS_PER_DAY); > > + } else { > > + /* The alarm register holds the number of seconds left. =20 > */ > > + time64_t time_now; > > + > > + ret =3D sun6i_rtc_gettime(dev, &tm_now); > > + if (ret < 0) { > > + dev_err(dev, "Error in getting time\n"); > > + return -EINVAL; > > + } > > + > > + time_now =3D rtc_tm_to_time64(&tm_now); > > + if (time_set <=3D time_now) { > > + dev_err(dev, "Date to set in the past\n"); > > + return -EINVAL; > > + } > > + if ((time_set - time_now) > U32_MAX) { > > + dev_err(dev, "Date too far in the future\n"); > > + return -EINVAL; > > + } > > + > > + counter_val =3D time_set - time_now; > > } > > =20 > > sun6i_rtc_setaie(0, chip); > > writel(0, chip->base + SUN6I_ALRM_COUNTER); > > + if (chip->flags & RTC_LINEAR_DAY) > > + writel(0, chip->base + SUN6I_ALRM_COUNTER_HMS); > > usleep_range(100, 300); > > =20 > > - writel(time_set - time_now, chip->base + SUN6I_ALRM_COUNTER); > > + writel(counter_val, chip->base + SUN6I_ALRM_COUNTER); > > + if (chip->flags & RTC_LINEAR_DAY) > > + writel(counter_val_hms, chip->base + =20 > SUN6I_ALRM_COUNTER_HMS); > > chip->alarm =3D time_set; > > =20 > > sun6i_rtc_setaie(wkalrm->enabled, chip); > > --=20 > > 2.17.6 > >=20 > > =20 >=20 >=20 >=20