From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ADDED3ECBDA; Fri, 4 Sep 2026 06:04:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788501878; cv=none; b=BgnNm95ycK8T63NVLAQfgnDNGBqlKcCE5UkHvOqufiEz7euVPKdCGiUEmjbwfY9O21KZCEI0qt5krdtX7kcUIPxPzF82R0FmC9GDMhzJve7QHMUiZUkLl6WsKPYw1Vip3yDTnw32+ZZq75ZX3xlBW/Es4supHinVY5u8rSP1jio= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788501878; c=relaxed/simple; bh=G4VAdgTj+f+2apfGI2xjIX+w3GjqiC4FP3cOYvm6pl4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dzHP+9USqYiWqETDVPQ1MCeR9wtwLlsH2Al/fL6g663KOttlUrz6fw3MNEAzZxIGmGaoyttAwt8flZws/S3UpKbWrL6e+OXf3Snp84ZFP/Ez+vUE1PyGFbDAPK2eD1ctZIomeWNwm3DqcvP7/W5U3dz++EiC8vxPTlUGrCcsEfc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cGwq6D7q; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cGwq6D7q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12EB21F00A3D; Fri, 4 Sep 2026 06:04:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788501877; bh=SL7sQw2XA1TQj34D8OdNEZqEOavaJEoUymsiW3/up4c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cGwq6D7qPMgb0BqRB5XrFBRgNBUTAkRWVBBXjMDLez6X2mBiQxL/TWvqoz1cVQkku 54VbFnudtMhruIQCMzwyTQ0SQ2kiwBT1L/Im8upFj03zXaj4XUmPU+3j+mlh1pU81+ 3HWcMVKpRPNwa/1RGGYLxpemv3FV77iIuYAk2tLE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Indrek Kruusa , Felix Yan , Daniel Lezcano , Jernej Skrabec Subject: [PATCH 6.12 012/403] clocksource/drivers/timer-sun4i: Advertise a real minimum delta Date: Fri, 4 Sep 2026 06:56:55 +0200 Message-ID: <20260904045735.090870322@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045734.806166532@linuxfoundation.org> References: <20260904045734.806166532@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Felix Yan commit d21808328225ab8cee46885bf9a0dffcefbe630e upstream. sun4i_clkevt_next_event() compensates for the timer stop/start synchronization delay by programming evt - TIMER_SYNC_TICKS into the hardware interval register. The clockevent device currently advertises TIMER_SYNC_TICKS as min_delta_ticks, so the clockevents core is allowed to call set_next_event() with evt == TIMER_SYNC_TICKS. That programs a zero-tick interval. With oneshot/highres/nohz timer operation this can leave the next event stuck, which was observed as a boot hang on Allwinner D1 after the clockevents core started reusing forced minimum-delta events. Advertise one extra tick instead, so the smallest event accepted by the core still programs at least one hardware tick after the synchronization compensation. Fixes: 12e1480bcb49 ("clocksource: sun4i: Report the minimum tick that we can program") Reported-by: Indrek Kruusa Closes: https://lore.kernel.org/linux-riscv/CA+fTLhgLmTY+exGujKf8OYYQvcEW5X5NJ_5sLq2AYL6zER2c0A@mail.gmail.com/ Assisted-by: Codex:gpt-5.5 Signed-off-by: Felix Yan Signed-off-by: Daniel Lezcano Tested-by: Indrek Kruusa Acked-by: Jernej Skrabec Cc: stable@vger.kernel.org Link: https://lore.kernel.org/linux-riscv/CA+fTLhgLmTY+exGujKf8OYYQvcEW5X5NJ_5sLq2AYL6zER2c0A@mail.gmail.com/ Link: https://patch.msgid.link/20260624220434.4183732-1-felixonmars@archlinux.org Signed-off-by: Greg Kroah-Hartman --- drivers/clocksource/timer-sun4i.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/clocksource/timer-sun4i.c +++ b/drivers/clocksource/timer-sun4i.c @@ -208,7 +208,7 @@ static int __init sun4i_timer_init(struc sun4i_timer_clear_interrupt(timer_of_base(&to)); clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), - TIMER_SYNC_TICKS, 0xffffffff); + TIMER_SYNC_TICKS + 1, 0xffffffff); /* Enable timer0 interrupt */ val = readl(timer_of_base(&to) + TIMER_IRQ_EN_REG);