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 B91183DBD46; Tue, 26 May 2026 10:25:57 +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=1779791159; cv=none; b=Sx+T+tWurw0bABM8SWtLIlytht0eEkMg+g/MEQasvM2HFeNppZpjyjeGm6GzDl2E9ulFSir7ikU6lZtROaQUOLF+FJ1rBKCMBMaRqoCW4C0R02gwbJYrtD7kuBqDcIoRXuhOFrZjDfo89R3CeySTCfmtTzJTrwuqqE7Fm5NXzq8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779791159; c=relaxed/simple; bh=gmQoQzsMPjGR/xUNYZs6D4VENZ7rn3xPTVp/FXyI4t0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ZWjH/Hd9svHbmBNg3Uows1lrGWdYPqpucx4Hf1xCUcwZpAVu/Aic9ybB+7lRYZ3SC244UyypY6n7L8nVbx6g8tBhb8htmqXW4/3IlaNSMmzwF13EShZCxeK9siU6E01cXQZvJRRvkw7cFkQgMTjo5BXNucpDd+X6irHRfyVJpRo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oIMni9ar; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oIMni9ar" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1603D1F000E9; Tue, 26 May 2026 10:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779791157; bh=t9FK9F0ke4Xrw2vcz0cJ/gpSi8fMZ+REQg2xafa71aQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=oIMni9arI4j1O+RUC0GS8hzWwEwGMcAUb1O9umjBUzW+9W+XgkIK3cbjbLU94CBWF pteGlsMocMOifalk+AoTzboPWohTKlcqnEL7oqvgKuwEsnLS12h1pg6gRydJYmQR5C lnJlAt9j5+mjWgi8Re6XyDMron/+MGAQu8NdZHVdt1DwfB1vTm6lEiDGXby8BgIJLk fIfu1vzPk0lOJgVUSptv5R/Fkr44TrMA/iOMQ65IvStY06NpwwOsF9OlUdEAR8Vwq5 MF3lG/K5sqOZ4/4QF0TzzAMhfY5ShTyKAD0SSzG3ewuPsOevZ0mDNOUsymwiwLsnsF R+lC2dvAiQ3PQ== Message-ID: Date: Tue, 26 May 2026 13:25:51 +0300 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 01/18] dmaengine: sh: rz-dmac: Move interrupt request after everything is set up To: Biju Das , "vkoul@kernel.org" , "Frank.Li@kernel.org" , "lgirdwood@gmail.com" , "broonie@kernel.org" , "perex@perex.cz" , "tiwai@suse.com" , Prabhakar Mahadev Lad , "p.zabel@pengutronix.de" , "geert+renesas@glider.be" , Kuninori Morimoto , Long Luu Cc: "Claudiu.Beznea" , "dmaengine@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-sound@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , Claudiu Beznea , "stable@vger.kernel.org" , Frank Li , John Madieu References: <20260526084710.3491480-1-claudiu.beznea@kernel.org> <20260526084710.3491480-2-claudiu.beznea@kernel.org> <8dcf50ee-94b7-4b27-895d-2448eb772c08@kernel.org> Content-Language: en-US From: Claudiu Beznea In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/26/26 12:51, Biju Das wrote: > Hi Claudiu, > >> -----Original Message----- >> From: Claudiu Beznea >> Sent: 26 May 2026 10:46 >> Subject: Re: [PATCH v6 01/18] dmaengine: sh: rz-dmac: Move interrupt request after everything is set >> up >> >> >> >> On 5/26/26 11:54, Biju Das wrote: >>> Hi Claudiu, >>> >>>> -----Original Message----- >>>> From: Claudiu Beznea >>>> Sent: 26 May 2026 09:47 >>>> Subject: [PATCH v6 01/18] dmaengine: sh: rz-dmac: Move interrupt >>>> request after everything is set up >>>> >>>> From: Claudiu Beznea >>>> >>>> Once the interrupt is requested, the interrupt handler may run immediately. >>> >>> Do you mean spurious interrupt? >>> >>> After DMA driver probe only, consumer device can access the DMA handle >>> right? or am I missing something here? >> >> In theory there could be pending interrupts not yet served (e.g. due to the previous usage of the >> controller, HW behavior, etc). Those could trigger the execution of the IRQ handler once the interrupt >> is requested. > > You mean DMA consumers configured by bootloader and linux probing the DMA driver can > trigger IRQ? DMA used by bootloaders may be a valid scenario, even though may not currently be used in the setups this IP is used. Please check the documentation of request_threaded_irq(): https://elixir.bootlin.com/linux/v7.1-rc4/source/kernel/irq/manage.c#L2089 "* ... From the point this call is made your handler function * may be invoked. Since your handler function must clear any interrupt the * board raises, you must take care both to initialise your hardware and to * set up the interrupt handler in the right order" -- Thank you, Claudiu