From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A2F63147C7D for ; Fri, 12 Apr 2024 15:34:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712936080; cv=none; b=n8eRj/8QUaUWqH9Ft/Wq+nglecYH8p62iJgBkBJ3Lyrkbzp7iMhlZqpn90fob6s7tDEvox3lTRZNkRV0QwuzZWTfXsWOExL7arqZXGhT4xXtbK5E5KmyksjL44ZbgE+J096GfW2d/c7BJJLTxuQpSmd+v1JrBMcOPg0Zkq349Vc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712936080; c=relaxed/simple; bh=xkYKPOI498KzpgzVZSU6RZmjpKWXLitmgQGEr4XGiTA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oER6XdOezR0ecqEVt6+lkprs0BI9aMnFUYyklO3dqNHJ05Wxc1H+RPFlxsP1G3PnjtTTrlij1sZg7V4H/yLmVbfyWQIZpe2R4anlVTtPUoAF67p+/N9ib8/Y8o3DwYD8Xyqo2ZDn3VtYE27K79j5T4aVbm6TGPhRT/tcUSGIzDU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JnIhge2z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JnIhge2z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9757C113CC; Fri, 12 Apr 2024 15:34:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712936080; bh=xkYKPOI498KzpgzVZSU6RZmjpKWXLitmgQGEr4XGiTA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JnIhge2zkirUvaSqDrtjBFRL8bG1w/Tqyxqt6VZ0HgH4qdAtP4jL3FkfGfixsVaD2 XyJlSpNBXuGPpuydT87PLgV3JTnAM4pkMMaHDRpzsqlT0L65ZnUuKp2VuyhvekyCJ+ N9HWNmiWcVAej0NEdq3gRIZRR9knaqe2ERhPNnas= Date: Fri, 12 Apr 2024 17:34:34 +0200 From: Greg KH To: Vamsi Krishna Attunuru Cc: "arnd@arndb.de" , "linux-kernel@vger.kernel.org" Subject: Re: [EXTERNAL] Re: [PATCH v5 1/1] misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver Message-ID: <2024041258-reminder-widely-00c0@gregkh> References: <20240412121005.1825881-1-vattunuru@marvell.com> <2024041250-nursing-tidy-db7e@gregkh> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Apr 12, 2024 at 01:56:36PM +0000, Vamsi Krishna Attunuru wrote: > > > > -----Original Message----- > > From: Greg KH > > Sent: Friday, April 12, 2024 5:57 PM > > To: Vamsi Krishna Attunuru > > Cc: arnd@arndb.de; linux-kernel@vger.kernel.org > > Subject: [EXTERNAL] Re: [PATCH v5 1/1] misc: mrvl-cn10k-dpi: add Octeon > > CN10K DPI administrative driver > > > > Prioritize security for external emails: Confirm sender and content safety > > before clicking links or opening attachments > > > > ---------------------------------------------------------------------- > > On Fri, Apr 12, 2024 at 05:10:05AM -0700, Vamsi Attunuru wrote: > > > Adds a misc driver for Marvell CN10K DPI(DMA Engine) device's physical > > > function which initializes DPI DMA hardware's global configuration and > > > enables hardware mailbox channels between physical function (PF) and > > > it's virtual functions (VF). VF device drivers (User space drivers) > > > use this hw mailbox to communicate any required device configuration > > > on it's respective VF device. Accordingly, this DPI PF driver > > > provisions the VF device resources. > > > > > > At the hardware level, the DPI physical function (PF) acts as a > > > management interface to setup the VF device resources, VF devices are > > > only provisioned to handle or control the actual DMA Engine's data transfer > > capabilities. > > > > No pointer to the userspace code that uses this? Why not? How are we > > supposed to be able to review this? > > Userspace code will use two functionalities (mailbox & ioctl) from this driver. DPDK DMA driver uses the mailbox and > the dpdk application uses the ioctl to setup the device attributes. We are waiting for this kernel driver get merged > to update the corresponding support in DPDK driver and applications. I will provide the pointers to both the use > cases in userspace code. > Meanwhile below is the current dpdk dma driver that uses sysfs based scheme to convey mbox requests to > the kernel DPI driver which gets replaced with hardware mailbox scheme once mrvl-cn10k-dpi kernel driver is merged. > https://github.com/DPDK/dpdk/blob/main/drivers/common/cnxk/roc_dpi.c So this is a DPDK thing? Ugh, do the networking people know about this? If not, why aren't they reviewing this? > > > + __u64 update_molr; /* '1' to update engine MOLR */ > > > > You "burn" a whole 64 for 1 bit? That feels wrong, who on your end > > reviewed this api to be correct? > > Just for the explicit alignment, defined all variables as __u64. I will shrink it to minimal sizes > considering any reserved fields if required. The alignment is fine, but wasting 63 bits feels odd, make it a bit field at worst case, or just make it __u8 if you don't want a bitfield. thanks, greg k-h