From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout09.his.huawei.com (canpmsgout09.his.huawei.com [113.46.200.224]) (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 7811429DB64; Mon, 20 Oct 2025 03:46:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.224 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760932008; cv=none; b=eeRMGCdy4NhOY88RL70L+IwkVZZHiFTrye227Vz9LTT25qjcQYjh9sIsj8Qisvqs/UDbSIfZllhhLsZKIjBXUGnm4ZAZ/Ow07u3Ue0/hrk2HBw2nrAQLIvcFHXY9OJcLBbawLdu6YS+17k3OxBQjbe6ges72Tqyfe9Kw6PloQk0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760932008; c=relaxed/simple; bh=iABrdS59ZBU4YHTm5ISf0PfyxAAqtPHL1MA1HLeuBqE=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=dwSOLDbt2SaO1DTZH+GMhAZYlqytJNe/VqDlC5tI5yB/SQPmHfHIrcomA3yBvHuZ6XPTiuMKulBM8HVsyOwzGBctxnDF+NywCordMyAJ5zbqwOjQ01z9FaGuOzPWrzB00Ha03EdOcsPmd7N1lYxh5wl7QH+gv+pzOkHd0+TGUxU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=h-partners.com; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b=oJPTzsWT; arc=none smtp.client-ip=113.46.200.224 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=h-partners.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b="oJPTzsWT" dkim-signature: v=1; a=rsa-sha256; d=h-partners.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=bDZQiErnIgzXG7MxUHsOCjYVCCcjyBfq4X2AfDHmv7U=; b=oJPTzsWTk2+N6N+1nrMFIqWn+foijoQW6PZTsAv2la39dooU9ZBzjqlc8d/Z7WybLEfZn7HVA S+jV+KgD5zpMQyzjkhDczOS+oGMse3hbeJjYo5GSvMB3cwC7dWkKyHoMKfkmg0yZsX5dBkx5mk2 pnwljSBYQunvAlVDM9kjclQ= Received: from mail.maildlp.com (unknown [172.19.88.234]) by canpmsgout09.his.huawei.com (SkyGuard) with ESMTPS id 4cqhDW1HR5z1cyQv; Mon, 20 Oct 2025 11:46:19 +0800 (CST) Received: from dggemv706-chm.china.huawei.com (unknown [10.3.19.33]) by mail.maildlp.com (Postfix) with ESMTPS id 5FA62140142; Mon, 20 Oct 2025 11:46:42 +0800 (CST) Received: from kwepemn100009.china.huawei.com (7.202.194.112) by dggemv706-chm.china.huawei.com (10.3.19.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 20 Oct 2025 11:46:42 +0800 Received: from [10.67.121.59] (10.67.121.59) by kwepemn100009.china.huawei.com (7.202.194.112) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 20 Oct 2025 11:46:41 +0800 Message-ID: <6b3ca901-025d-44b8-9558-6ad5a491807e@huawei.com> Date: Mon, 20 Oct 2025 11:46:37 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/6] Revert "mailbox/pcc: support mailbox management of the shared buffer" To: Sudeep Holla , , CC: Adam Young , Robbie King , Jassi Brar , "Cristian Marussi" References: <20251016-pcc_mb_updates-v1-0-0fba69616f69@arm.com> <20251016-pcc_mb_updates-v1-1-0fba69616f69@arm.com> From: "lihuisong (C)" In-Reply-To: <20251016-pcc_mb_updates-v1-1-0fba69616f69@arm.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems100001.china.huawei.com (7.221.188.238) To kwepemn100009.china.huawei.com (7.202.194.112) 在 2025/10/17 3:08, Sudeep Holla 写道: > This reverts commit 5378bdf6a611a32500fccf13d14156f219bb0c85. > > Commit 5378bdf6a611 ("mailbox/pcc: support mailbox management of the shared buffer") > attempted to introduce generic helpers for managing the PCC shared memory, > but it largely duplicates functionality already provided by the mailbox > core and leaves gaps: > > 1. TX preparation: The mailbox framework already supports this via > ->tx_prepare callback for mailbox clients. The patch adds > pcc_write_to_buffer() and expects clients to toggle pchan->chan.manage_writes, > but no drivers set manage_writes, so pcc_write_to_buffer() has no users. > > 2. RX handling: Data reception is already delivered through > mbox_chan_received_data() and client ->rx_callback. The patch adds an > optional pchan->chan.rx_alloc, which again has no users and duplicates > the existing path. > > 3. Completion handling: While adding last_tx_done is directionally useful, > the implementation only covers Type 3/4 and fails to handle the absence > of a command_complete register, so it is incomplete for other types. > > Given the duplication and incomplete coverage, revert this change. Any new > requirements should be addressed in focused follow-ups rather than bundling > multiple behavioral changes together. > > Fixes: 5378bdf6a611 ("mailbox/pcc: support mailbox management of the shared buffer") > Signed-off-by: Sudeep Holla Yeah, there are some duplications. I remember I also mentioned before. Acked-by: lihuisong@huawei.com