From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1751942AbbCJG1S (ORCPT <rfc822;w@1wt.eu>);
	Tue, 10 Mar 2015 02:27:18 -0400
Received: from mailgw01.mediatek.com ([210.61.82.183]:40602 "EHLO
	mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org
	with ESMTP id S1751277AbbCJG1Q (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Tue, 10 Mar 2015 02:27:16 -0400
X-Listener-Flag: 11101
Subject: Re: [PATCH 1/5] soc: mediatek: Add SMI driver
From: Yingjoe Chen <yingjoe.chen@mediatek.com>
To: Arnd Bergmann <arnd@arndb.de>
CC: <linux-arm-kernel@lists.infradead.org>,
        Mark Rutland <mark.rutland@arm.com>, <devicetree@vger.kernel.org>,
        <linux-mediatek@lists.infradead.org>, <srv_heupstream@mediatek.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will.deacon@arm.com>,
        <linux-kernel@vger.kernel.org>, Tomasz Figa <tfiga@google.com>,
        <iommu@lists.linux-foundation.org>, Rob Herring <robh+dt@kernel.org>,
        Daniel Kurtz <djkurtz@google.com>, Sasha Hauer <kernel@pengutronix.de>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Robin Murphy <robin.murphy@arm.com>, <yong.wu@mediatek.com>,
        Lucas Stach <l.stach@pengutronix.de>
In-Reply-To: <2583132.xxsZocsQta@wuerfel>
References: <1425638900-24989-1-git-send-email-yong.wu@mediatek.com>
	 <1425638900-24989-2-git-send-email-yong.wu@mediatek.com>
	 <1425871612.4871.10.camel@mtksdaap41>  <2583132.xxsZocsQta@wuerfel>
Content-Type: text/plain; charset="UTF-8"
Date: Tue, 10 Mar 2015 14:27:04 +0800
Message-ID: <1425968824.4871.146.camel@mtksdaap41>
MIME-Version: 1.0
X-Mailer: Evolution 2.28.3 
Content-Transfer-Encoding: 7bit
X-MTK: N
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, 2015-03-09 at 22:56 +0100, Arnd Bergmann wrote:
> On Monday 09 March 2015 11:26:52 Yingjoe Chen wrote:
> > On Fri, 2015-03-06 at 18:48 +0800, yong.wu@mediatek.com wrote:
> > > From: Yong Wu <yong.wu@mediatek.com>
> > > 
> > >     This patch add SMI(Smart Multimedia Interface) driver. This driver is
> > > responsible to enable/disable iommu and control the clocks of each
> > > local arbiter.
> > > 
> > > Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> > > ---
> > >  drivers/soc/mediatek/Kconfig      |   7 ++
> > >  drivers/soc/mediatek/Makefile     |   1 +
> > >  drivers/soc/mediatek/mt8173-smi.c | 143 ++++++++++++++++++++++++++++++++++++++
> > >  include/linux/mtk-smi.h           |  40 +++++++++++
> > >  4 files changed, 191 insertions(+)
> > >  create mode 100644 drivers/soc/mediatek/mt8173-smi.c
> > >  create mode 100644 include/linux/mtk-smi.h
> > > 
> > 
> > Hi Arnd, Matthias,
> > 
> > For the SMI driver, we can't find a better place, so we put it in
> > drivers/soc/mediatek now. Please let us know if you have any suggestion
> > or concern. Thanks
> 
> From what I understand from your description, I think it would better
> fit in drivers/iommu. Another option is drivers/memory, which I think
> is where the respective Tegra driver ended up.

Hi Arnd,

The description above only describe what is implemented now. Besides
that, SMI HW also does:

- Prioritize/arbitrate memory requests between different ports & larbs.
- Bandwidth limiter
- Performance monitor

I think drivers/memory make more sense. I can't find info about
drivers/memory in MAINTAINERS. Can this go through ARM SoC tree if we
put SMI driver there?

Joe.C