From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [[PATCH] 8/9] DMA-UART-Driver-for-AST2500 Date: Fri, 19 Oct 2018 10:32:24 +1100 Message-ID: References: <1539749466-3912-1-git-send-email-open.sudheer@gmail.com> <1539749466-3912-9-git-send-email-open.sudheer@gmail.com> <20181017060531.GU2400@vkoul-mobl> <351eecd5b1b21893e94f76b34c058c6257b7f837.camel@kernel.crashing.org> <20181018095507.GC2400@vkoul-mobl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181018095507.GC2400@vkoul-mobl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Vinod Cc: Mark Rutland , Kate Stewart , linux-aspeed@lists.ozlabs.org, Hendrik Brueckner , Thomas Gleixner , Michael Moese , Russell King , Christian Borntraeger , Joel Stanley , linux-serial@vger.kernel.org, Jiri Slaby , devicetree@vger.kernel.org, Marc Zyngier , ShivahShankar Shakarnarayan rao , Rob Herring , Dan Williams , linux-arm-kernel@lists.infradead.org, Sudheer V , Andrew Jeffery , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, "sudheer.v" , Philippe List-Id: devicetree@vger.kernel.org On Thu, 2018-10-18 at 15:25 +0530, Vinod wrote: > > > It's not a dmaengine driver. It's a serial UART driver that happens to > > use a dedicated DMA engine. > > Then I see no reason for it to use dmaengine APIs. The framework allows > people to share a controller for many clients, but if you have dedicated > one then you may use it directly Well... the engine is shared by a few UARTs, they have dedicated rings but there's a common set of regs for interrupt handling etc. That said, I still think it could be contained within a UART driver, there's little benefit in adding the framework overhead, esp since these are really weak cores, any overhead will be felt. Ben. > > It's unclear whether it should be split into two drivers, or just have > > the serial driver directly use the dma engine since that engine is > > dedicated in HW to only work on those UARTs and nothing else... > > > > Cheers, > > Ben. > > > > > > > While doing resubmission please take some time to understand subsystem > > > tags to use. (hint git log will tell you) > > > > > > Also series has [[PATCH] 8/9] whereas it should be [PATCH 8/9] please > > > let git generate that for you (hint git format-patch start..end does a > > > good job) > > > > > > > @@ -0,0 +1,1594 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > +/* > > > > + * drivers/tty/serial/8250/8250_aspeed_uart_dma.c > > > > + * 1. 2018/07/01 Shivah Shankar created > > > > + * 2. 2018/08/25 sudheer.veliseti modified > > > > > > we dont use this log in kernel. I do not see s-o-b by Shivah, that > > > should be added. I think he should be author and you need to list > > > changes you did.. > > > > >