Linux-mediatek Archive on lore.kernel.org
 help / color / Atom feed
From: chao hao <Chao.Hao@mediatek.com>
To: Matthias Brugger <matthias.bgg@gmail.com>
Cc: devicetree@vger.kernel.org, FY Yang <fy.yang@mediatek.com>,
	wsd_upstream@mediatek.com, Joerg Roedel <joro@8bytes.org>,
	linux-kernel@vger.kernel.org, Evan Green <evgreen@chromium.org>,
	Chao Hao <chao.hao@mediatek.com>,
	iommu@lists.linux-foundation.org,
	Rob Herring <robh+dt@kernel.org>,
	linux-mediatek@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	Yong Wu <yong.wu@mediatek.com>
Subject: Re: [PATCH v5 09/10] iommu/mediatek: Modify MMU_CTRL register setting
Date: Tue, 30 Jun 2020 19:02:21 +0800
Message-ID: <1593514941.13270.6.camel@mbjsdccf07> (raw)
In-Reply-To: <e063a5d2-8edc-9cf9-4872-d3f4abb1e481@gmail.com>

On Mon, 2020-06-29 at 12:28 +0200, Matthias Brugger wrote:
> 
> On 29/06/2020 09:13, Chao Hao wrote:
> > MT8173 is different from other SoCs for MMU_CTRL register.
> > For mt8173, its bit9 is in_order_write_en and doesn't use its
> > default 1'b1.> For other SoCs, bit[12] represents victim_tlb_en feature and
> > victim_tlb is enable defaultly(bit[12]=1), if we use
> > "regval = F_MMU_TF_PROT_TO_PROGRAM_ADDR", victim_tlb will be
> > disabled, it will drop iommu performace.
> > So we need to deal with the setting of MMU_CTRL separately
> > for mt8173 and others.
> > 
> 
> My proposal to rewrite the commit message:
> 
> The MMU_CTRL regiser of MT8173 is different from other SoCs. The in_order_wr_en
> is bit[9] which is zero by default.
> Other SoCs have the vitcim_tlb_en feature mapped to bit[12]. This bit is set to
> one by default. We need to preserve the bit when setting
> F_MMU_TF_PROT_TO_PROGRAM_ADDR as otherwise the bit will be cleared and IOMMU
> performance will drop.

got it, thanks for your advice very much.

> 
> 
> > Suggested-by: Matthias Brugger <matthias.bgg@gmail.com>
> > Suggested-by: Yong Wu <yong.wu@mediatek.com>
> > Signed-off-by: Chao Hao <chao.hao@mediatek.com>
> > ---
> >  drivers/iommu/mtk_iommu.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> > index 8299a3299090..e46e2deee3fd 100644
> > --- a/drivers/iommu/mtk_iommu.c
> > +++ b/drivers/iommu/mtk_iommu.c
> > @@ -543,11 +543,12 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
> >  		return ret;
> >  	}
> >  
> > +	regval = readl_relaxed(data->base + REG_MMU_CTRL_REG);
> 
> The read is only needed in the else branch.
> 
ok, thanks

> >  	if (data->plat_data->m4u_plat == M4U_MT8173)
> >  		regval = F_MMU_PREFETCH_RT_REPLACE_MOD |
> >  			 F_MMU_TF_PROT_TO_PROGRAM_ADDR_MT8173;
> >  	else
> > -		regval = F_MMU_TF_PROT_TO_PROGRAM_ADDR;
> > +		regval |= F_MMU_TF_PROT_TO_PROGRAM_ADDR;
> >  	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
> >  
> >  	regval = F_L2_MULIT_HIT_EN |
> > 

_______________________________________________
Linux-mediatek mailing list
Linux-mediatek@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-mediatek

  reply index

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-29  7:13 [PATCH v5 00/10] MT6779 IOMMU SUPPORT Chao Hao
2020-06-29  7:13 ` [PATCH v5 01/10] dt-bindings: mediatek: Add bindings for MT6779 Chao Hao
2020-06-29  7:13 ` [PATCH v5 02/10] iommu/mediatek: Rename the register STANDARD_AXI_MODE(0x48) to MISC_CTRL Chao Hao
2020-07-01  2:17   ` Yong Wu
2020-07-03  2:36     ` chao hao
2020-06-29  7:13 ` [PATCH v5 03/10] iommu/mediatek: Modify the usage of mtk_iommu_plat_data structure Chao Hao
2020-06-29  9:11   ` Matthias Brugger
2020-06-30 10:56   ` Yong Wu
2020-06-30 11:55     ` chao hao
2020-06-29  7:13 ` [PATCH v5 04/10] iommu/mediatek: Setting MISC_CTRL register Chao Hao
2020-06-29  9:28   ` Matthias Brugger
2020-06-30 10:53     ` chao hao
2020-07-01 14:58       ` Matthias Brugger
2020-07-03  2:38         ` chao hao
2020-06-29  7:13 ` [PATCH v5 05/10] iommu/mediatek: Move inv_sel_reg into the plat_data Chao Hao
2020-06-29  7:13 ` [PATCH v5 06/10] iommu/mediatek: Add sub_comm id in translation fault Chao Hao
2020-06-30 10:55   ` Yong Wu
2020-06-30 11:07     ` chao hao
2020-06-29  7:13 ` [PATCH v5 07/10] iommu/mediatek: Add REG_MMU_WR_LEN register definition Chao Hao
2020-06-29 10:16   ` Matthias Brugger
2020-06-30 10:59     ` chao hao
2020-07-01 15:00       ` Matthias Brugger
2020-06-29  7:13 ` [PATCH v5 08/10] iommu/mediatek: Extend protect pa alignment value Chao Hao
2020-06-29 10:17   ` Matthias Brugger
2020-06-29  7:13 ` [PATCH v5 09/10] iommu/mediatek: Modify MMU_CTRL register setting Chao Hao
2020-06-29 10:28   ` Matthias Brugger
2020-06-30 11:02     ` chao hao [this message]
2020-06-29  7:13 ` [PATCH v5 10/10] iommu/mediatek: Add mt6779 basic support Chao Hao
2020-06-29 10:29   ` Matthias Brugger

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1593514941.13270.6.camel@mbjsdccf07 \
    --to=chao.hao@mediatek.com \
    --cc=devicetree@vger.kernel.org \
    --cc=evgreen@chromium.org \
    --cc=fy.yang@mediatek.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=joro@8bytes.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=matthias.bgg@gmail.com \
    --cc=robh+dt@kernel.org \
    --cc=wsd_upstream@mediatek.com \
    --cc=yong.wu@mediatek.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-mediatek Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mediatek/0 linux-mediatek/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mediatek linux-mediatek/ https://lore.kernel.org/linux-mediatek \
		linux-mediatek@lists.infradead.org
	public-inbox-index linux-mediatek

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-mediatek


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git