From mboxrd@z Thu Jan 1 00:00:00 1970 From: houlong wei Subject: Re: FW: [PATCH v20 2/4] mailbox: mediatek: Add Mediatek CMDQ driver Date: Thu, 18 Jan 2018 16:31:53 +0800 Message-ID: <1516264313.16602.30.camel@mhfsdcap03> References: <1483499169-16329-1-git-send-email-hs.liao@mediatek.com> <1483499169-16329-3-git-send-email-hs.liao@mediatek.com> <1485419833.990.1.camel@mtksdaap41> <1486359476.11424.33.camel@mtksdaap41> <1487733150.15869.11.camel@mtksdaap41> <1487854104.17813.1.camel@mtksdaap41> <497f8e4ef7ae4c8a9b7b4ab259801306@mtkmbs01n1.mediatek.inc> <1515400735.21044.35.camel@mhfsdcap03> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jassi Brar Cc: Rob Herring , Matthias Brugger , Daniel Kurtz , Sascha Hauer , Devicetree List , Linux Kernel Mailing List , linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, srv_heupstream , Sascha Hauer , Philipp Zabel , Nicolas Boichat , CK Hu =?UTF-8?Q?=28=E8=83=A1=E4=BF=8A=E5=85=89=29?= , Cawa Cheng =?UTF-8?Q?=28=E9=84=AD=E6=9B=84=E7=A6=A7=29?= , Bibby Hsieh =?UTF-8?Q?=28=E8=AC=9D=E6=BF=9F=E9=81=A0=29?= Y List-Id: devicetree@vger.kernel.org Hi Jassi, There is one request for one GCE h/w buffer which contains a list of registers operation. I will resubmit a version and please review again. Thanks, Houlong On Thu, 2018-01-18 at 16:01 +0800, Jassi Brar wrote: > On Mon, Jan 8, 2018 at 2:08 PM, houlong wei wrote: > > Hi Jassi, > > > > Sorry for reply so late. > > According to previous discussion, there are two methods to move > > dma_map_single() outside of spin_lock. > > (1) put in mtk-cmdq-helper.c, as described by HS on 2017-02-09. > > > I think a trade-off solution is to put in mtk-cmdq-helper.c. > > > Although it is a mailbox client, it is not a CMDQ client. > > > We can include mailbox_controller.h in mtk-cmdq-helper.c (instead of > > mtk-cmdq.h), and then map dma at cmdq_pkt_flush_async before > > mbox_send_message. > > > > > pkt->pa_base = dma_map_single(client->chan->mbox->dev, pkt->va_base, > > > pkt->cmd_buf_size, DMA_TO_DEVICE); > > (2) schedule a tasklet in send_data(). > > > > After internal discussion with HS and other experts, now we prefer > > method (1). > > How do you think about it? > > > I don't exactly see how you mean but please remember send_data() > callback is supposed to be atomic ... it is protected by > spin_lock_irqsave/restore in drivers/mailbox/mailbox.c:msg_submit() > > BTW, how many requests max can be queued in the GCE h/w buffer? > And since it's been over a year now, could you please resubmit after > checking for checkpatch with the --strict option? > > Thanks. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html