From patchwork Fri Dec 10 20:01:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Mateusz_Jo=C5=84czyk?= X-Patchwork-Id: 1566638 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=o2.pl header.i=@o2.pl header.a=rsa-sha256 header.s=1024a header.b=qxnUntqh; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by bilbo.ozlabs.org (Postfix) with ESMTP id 4J9hdp2Nzdz9s3q for ; Sat, 11 Dec 2021 07:02:38 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240626AbhLJUGM (ORCPT ); Fri, 10 Dec 2021 15:06:12 -0500 Received: from mx-out.tlen.pl ([193.222.135.142]:31313 "EHLO mx-out.tlen.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343976AbhLJUGJ (ORCPT ); Fri, 10 Dec 2021 15:06:09 -0500 Received: (wp-smtpd smtp.tlen.pl 599 invoked from network); 10 Dec 2021 21:02:32 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=o2.pl; s=1024a; t=1639166552; bh=0HUvyNzB/Qh98ao9Qn1RSPIaWiEazGlrC7sQMYoP7Xw=; h=From:To:Cc:Subject; b=qxnUntqh30cDJuJmwautFkASwQspt6o2RU0MMQ+XE+/t20hAZpB832RKK4Rp8snyF Cpk3/JS99GJIQXCwLlP3FMhsKRXWfFpwqv5BWOC2ByfJ3F3HTs2Tr5YaPy8AX7MdpR t101ik8C/nX2JmgwRzZ/AxYm1O3uouG7stdz7gDo= Received: from aaff136.neoplus.adsl.tpnet.pl (HELO localhost.localdomain) (mat.jonczyk@o2.pl@[83.4.135.136]) (envelope-sender ) by smtp.tlen.pl (WP-SMTPD) with SMTP for ; 10 Dec 2021 21:02:32 +0100 From: =?utf-8?q?Mateusz_Jo=C5=84czyk?= To: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: =?utf-8?q?Mateusz_Jo=C5=84czyk?= , Alessandro Zummo , Alexandre Belloni Subject: [PATCH v4 6/9] rtc-mc146818-lib: refactor mc146818_get_time Date: Fri, 10 Dec 2021 21:01:28 +0100 Message-Id: <20211210200131.153887-7-mat.jonczyk@o2.pl> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211210200131.153887-1-mat.jonczyk@o2.pl> References: <20211210200131.153887-1-mat.jonczyk@o2.pl> MIME-Version: 1.0 X-WP-MailID: 8192778acea93e0ec07c262b1754b881 X-WP-AV: skaner antywirusowy Poczty o2 X-WP-SPAM: NO 0000000 [0WME] Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org Refactor mc146818_get_time() so that it uses mc146818_avoid_UIP(). Signed-off-by: Mateusz Jończyk Cc: Alessandro Zummo Cc: Alexandre Belloni --- I'm sorry that the diff is so unreadable, but I was unable to fix this easily. drivers/rtc/rtc-mc146818-lib.c | 109 +++++++++++++-------------------- 1 file changed, 42 insertions(+), 67 deletions(-) diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c index b20f4ebb2f3a..15604b7f164d 100644 --- a/drivers/rtc/rtc-mc146818-lib.c +++ b/drivers/rtc/rtc-mc146818-lib.c @@ -103,49 +103,20 @@ bool mc146818_does_rtc_work(void) } EXPORT_SYMBOL_GPL(mc146818_does_rtc_work); -unsigned int mc146818_get_time(struct rtc_time *time) -{ +struct mc146818_get_time_callback_param { + struct rtc_time *time; unsigned char ctrl; - unsigned long flags; - unsigned int iter_count = 0; - unsigned char century = 0; - bool retry; - +#ifdef CONFIG_ACPI + unsigned char century; +#endif #ifdef CONFIG_MACH_DECSTATION unsigned int real_year; #endif +}; -again: - if (iter_count > 10) { - memset(time, 0, sizeof(*time)); - return -EIO; - } - iter_count++; - - spin_lock_irqsave(&rtc_lock, flags); - - /* - * Check whether there is an update in progress during which the - * readout is unspecified. The maximum update time is ~2ms. Poll - * every msec for completion. - * - * Store the second value before checking UIP so a long lasting NMI - * which happens to hit after the UIP check cannot make an update - * cycle invisible. - */ - time->tm_sec = CMOS_READ(RTC_SECONDS); - - if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) { - spin_unlock_irqrestore(&rtc_lock, flags); - mdelay(1); - goto again; - } - - /* Revalidate the above readout */ - if (time->tm_sec != CMOS_READ(RTC_SECONDS)) { - spin_unlock_irqrestore(&rtc_lock, flags); - goto again; - } +static void mc146818_get_time_callback(unsigned char seconds, void *param_in) +{ + struct mc146818_get_time_callback_param *p = param_in; /* * Only the values that we read from the RTC are set. We leave @@ -153,39 +124,39 @@ unsigned int mc146818_get_time(struct rtc_time *time) * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated * by the RTC when initially set to a non-zero value. */ - time->tm_min = CMOS_READ(RTC_MINUTES); - time->tm_hour = CMOS_READ(RTC_HOURS); - time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); - time->tm_mon = CMOS_READ(RTC_MONTH); - time->tm_year = CMOS_READ(RTC_YEAR); + p->time->tm_sec = seconds; + p->time->tm_min = CMOS_READ(RTC_MINUTES); + p->time->tm_hour = CMOS_READ(RTC_HOURS); + p->time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); + p->time->tm_mon = CMOS_READ(RTC_MONTH); + p->time->tm_year = CMOS_READ(RTC_YEAR); #ifdef CONFIG_MACH_DECSTATION - real_year = CMOS_READ(RTC_DEC_YEAR); + p->real_year = CMOS_READ(RTC_DEC_YEAR); #endif #ifdef CONFIG_ACPI if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID && - acpi_gbl_FADT.century) - century = CMOS_READ(acpi_gbl_FADT.century); + acpi_gbl_FADT.century) { + p->century = CMOS_READ(acpi_gbl_FADT.century); + } else { + p->century = 0; + } #endif - ctrl = CMOS_READ(RTC_CONTROL); - /* - * Check for the UIP bit again. If it is set now then - * the above values may contain garbage. - */ - retry = CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP; - /* - * A NMI might have interrupted the above sequence so check whether - * the seconds value has changed which indicates that the NMI took - * longer than the UIP bit was set. Unlikely, but possible and - * there is also virt... - */ - retry |= time->tm_sec != CMOS_READ(RTC_SECONDS); - spin_unlock_irqrestore(&rtc_lock, flags); + p->ctrl = CMOS_READ(RTC_CONTROL); +} - if (retry) - goto again; +unsigned int mc146818_get_time(struct rtc_time *time) +{ + struct mc146818_get_time_callback_param p = { + .time = time + }; + + if (!mc146818_avoid_UIP(mc146818_get_time_callback, &p)) { + memset(time, 0, sizeof(*time)); + return -EIO; + } - if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) + if (!(p.ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { time->tm_sec = bcd2bin(time->tm_sec); time->tm_min = bcd2bin(time->tm_min); @@ -193,15 +164,19 @@ unsigned int mc146818_get_time(struct rtc_time *time) time->tm_mday = bcd2bin(time->tm_mday); time->tm_mon = bcd2bin(time->tm_mon); time->tm_year = bcd2bin(time->tm_year); - century = bcd2bin(century); +#ifdef CONFIG_ACPI + p.century = bcd2bin(p.century); +#endif } #ifdef CONFIG_MACH_DECSTATION - time->tm_year += real_year - 72; + time->tm_year += p.real_year - 72; #endif - if (century > 20) - time->tm_year += (century - 19) * 100; +#ifdef CONFIG_ACPI + if (p.century > 20) + time->tm_year += (p.century - 19) * 100; +#endif /* * Account for differences between how the RTC uses the values