From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr2-f35.google.com (mail-wr2-f35.google.com [74.125.225.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C8A82547059 for ; Thu, 1 Oct 2026 06:54:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.225.99 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790837661; cv=none; b=InIRt7j6D3QDuObEwP1P8VAwl0edfA2eHuMh0JRKYTX/Wgn2Abe9L8s+b9f4FuRJzojy2q+cvgHrjIAlcyT1SaIe+d/TPD8LzB+8LDILIa4UOEo3q8F6dstQjB1nS7XTSHT1mvCizb8+6Hd6MwQCMLqk8bVPjVTGo7LGlFuDiQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790837661; c=relaxed/simple; bh=OQGFboAIgaxsHZXP29Wd9s2vQCVrfmH798k2j+zX9Gs=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=nNcAxXhS3QOQVa+soYkM2F2UJtqzDhcEFf4H8bQrUT+olm8aEqzDUwW1+4TbPmZKcf6h0fVTK948o18AscQflHl6CCyoRjQo6r/BVFISXagZyBYbV+z4eB1JLmCIuBC9g49y9OuB6OpoIssqIJvm99DtkkM3svOO9+wUY5jMfLs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=HxtEQIrP; arc=none smtp.client-ip=74.125.225.99 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="HxtEQIrP" Received: by mail-wr2-f35.google.com with SMTP id ffacd0b85a97d-48b05fdb2f9so649788f8f.0 for ; Wed, 30 Sep 2026 23:54:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790837658; x=1791442458; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:content-type :references:in-reply-to:date:cc:to:from:subject:message-id:from:to :cc:subject:date:message-id:reply-to:content-type; bh=dQM3nzcaHIpaT+Z8HPZx7VZW+Ub3Nz7sGdgKg0hJno4=; b=HxtEQIrPevPbWFEGyq415CdLzCbBgdicvRTVqcjxdTmACiTBZFSvXiehx8qwTGcEME wdw1RWJA1tfBWOTEn5lIpqr/McFl2pTIH1mUb996L4mDsvol2XmBsOjnz1Qm7mEfnRkS V+hsScH9cWAWNS2/ISRy/jse4foUpTnsvFYSt0CChnnx19KiOKvdYmm3gYh2JtZ1xWaZ ICXe2LIESM5oHhnblNqp3a5ulURqW+HU7GiHYaOZ87ItXLqk6rAbneIdw2ZgCYsUbAQs tAN8nkJOSyNkic9oT7TXgHdb/VjVPmM6n1MFPXnKMuXeKSnPTu8a+0hoIjjq8WmMnk94 khRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790837658; x=1791442458; h=mime-version:user-agent:content-transfer-encoding:content-type :references:in-reply-to:date:cc:to:from:subject:message-id:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=dQM3nzcaHIpaT+Z8HPZx7VZW+Ub3Nz7sGdgKg0hJno4=; b=SqCd3wY6lmK+/oW9cwscN9hwEmtN/fwd0dTvljqjpsInL/co94VR+jD20sQiH+XLcQ ufLazJvHDrTcOTjC2inXAVhQDf/Bb8dUjdCk9ARKRHEtsprQV9ZtCAQrkTHArtQUoEQT KSj1BLSSa4rZ0eEgaLr/WBIjKLoA+yEfjAaETxAcfyjzv8KcWPqJjYAh7sJt6pniZwx3 qWZfaEC25ENKgjwtyxOnZydTLOg8rWEQ7zp4c/Mh1te373Wy50qGtCDW/eTCCJU59zDa 81+o0DvuxZKcrOfPjUVandMjpytwhnGWFrQ0d527lAFbJZeALHm3C054sXBDcarxUS8w n2jA== X-Gm-Message-State: AFq9FYJxvIH5lURKUVG/yM+QbVIgC6u52jFEktdAvdFuzS2bBwNDGmY2 Yx9z80hGuBP8scaGWNhePuZ0K1DY/3X9jlWRV8P6fK4ZrXY35+doyoy8 X-Gm-Gg: AYBFou3c+0BYobIX+I8QtfCsZjVfdneEIi207QnkFf/82T9xyIwjE+LBu58nfWGlFIh nXawoJl1eIl1oh9ogRRRGuUdubJIRvqBZqRbV0KQ4KZH5MXD+LhWU0eOPOZ8fjfQS8TuJ0h6iQC RhVe52zpNKRWvraE9BLSYNY9iYmhuCuYxV9E/SDmyALJTd+smD13JrJMRcwVOWBV2Sl1WajYblV LCKK5UL1D8Flr+/LjD8x72u3uDI+xG7OHbE3E/9W1ITduxNUrv5nX0jMLt4vxxF1JrG3KMGXIsh V288H8ImfK4AH0ZJsAMt29nX43hRFnTie/8l9RUaa0Blaz347iydeobBxzvqnuODcD6o2VTUemX d9yNd9MD1m/eJzTH/KnxXcUGDYGsj20vpxflSZo6Oi/6BcG/+PevL3iNRBVFrGw9fwILUwFivXt ma/DcAdfHXo/pvZp7cAipQeYqK99jkOhlgkjvhZC/khE4RzASaTI4bajIGwSIHwBNqfqexn1dHH koo8OVdRBdqIBIteHXQYEkt4INEwZDouNWO/LZphk0KzBBu+ROuyS/XaKjjjTQRtL2OXtvHVEo6 M79k3A== X-Received: by 2002:a5d:5e0f:0:b0:486:e9ab:2b88 with SMTP id ffacd0b85a97d-48b02a9f53bmr3865955f8f.24.1790837657921; Wed, 30 Sep 2026 23:54:17 -0700 (PDT) Received: from ?IPv6:2001:818:ea56:d000:56e0:ceba:7da4:6673? ([2001:818:ea56:d000:56e0:ceba:7da4:6673]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48b068bc944sm4283186f8f.3.2026.09.30.23.54.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Sep 2026 23:54:17 -0700 (PDT) Message-ID: Subject: Re: [PATCH v2 2/2] spi: axi-spi-engine: fix stale SYNC IRQ pending in trigger_enable From: Nuno =?ISO-8859-1?Q?S=E1?= To: Mark Brown , Jonathan Santos Cc: linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, dlechner@baylibre.com, nuno.sa@analog.com, michael.hennerich@analog.com, jonath4nns@gmail.com, andriy.shevchenko@intel.com Date: Thu, 01 Oct 2026 07:55:45 +0100 In-Reply-To: <8ba05b99-36ac-4a76-ac11-e6ad92c631d4@sirena.org.uk> References: <8ba05b99-36ac-4a76-ac11-e6ad92c631d4@sirena.org.uk> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Wed, 2026-09-30 at 14:09 +0100, Mark Brown wrote: > On Tue, Sep 29, 2026 at 11:17:45PM -0300, Jonathan Santos wrote: > > spi_engine_trigger_enable() sends SYNC(1) and polls SYNC_ID, it never > > clears the INT_PENDING[SYNC] bit afterward. This leaves a stale pending > > interrupt that can fire spuriously when INT_SYNC is later enabled. >=20 > > + > > + /* Clear the stale SYNC pending bit so it doesn't fire when the IRQ i= s > > later enabled */ > > + writel_relaxed(SPI_ENGINE_INT_SYNC, spi_engine->base + > > SPI_ENGINE_REG_INT_PENDING); > > + > > =C2=A0 if (ret) > > =C2=A0 return ret; >=20 > I'm not seeing anything here for the issue with ensuring posted writes > are completed before we drop the lock?=C2=A0 The write may not be visible= on > enother CPU, we need a read from the controller or something. Just for my understanding, why would it be an issue? The trigger register s= eems to only be accessible from the trigger callbacks which are protected by a lock= where we have implied barriers. Im sure I'm missing what can go wrong here :) - Nuno S=C3=A1