From: Robin Murphy <robin.murphy@arm.com>
To: Yong Wu <yong.wu@mediatek.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
Joerg Roedel <joro@8bytes.org>, Will Deacon <will.deacon@arm.com>
Cc: youlin.pei@mediatek.com, anan.sun@mediatek.com,
Nicolas Boichat <drinkcat@chromium.org>,
cui.zhang@mediatek.com, srv_heupstream@mediatek.com,
chao.hao@mediatek.com, edison.hsieh@mediatek.com,
linux-kernel@vger.kernel.org, Evan Green <evgreen@chromium.org>,
Tomasz Figa <tfiga@google.com>,
iommu@lists.linux-foundation.org,
linux-mediatek@lists.infradead.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 6/7] iommu/mediatek: Use writel for TLB range invalidation
Date: Mon, 14 Oct 2019 15:04:42 +0100 [thread overview]
Message-ID: <c87e2a9c-5ed3-e44c-3b17-067db173eae9@arm.com> (raw)
In-Reply-To: <1571035101-4213-7-git-send-email-yong.wu@mediatek.com>
On 14/10/2019 07:38, Yong Wu wrote:
> Use writel for the register F_MMU_INV_RANGE which is for triggering the
> HW work. We expect all the setting(iova_start/iova_end...) have already
> been finished before F_MMU_INV_RANGE.
For Arm CPUs, these registers should be mapped as Device memory,
therefore the same-peripheral rule should implicitly enforce that the
accesses are made in program order, hence you're unlikely to have seen a
problem in reality. However, the logical reasoning for the change seems
valid in general, so I'd argue that it's still worth making if only for
the sake of good practice:
Acked-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Anan.Sun <anan.sun@mediatek.com>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> ---
> drivers/iommu/mtk_iommu.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index dbbacc3..d285457 100644
> --- a/drivers/iommu/mtk_iommu.c
> +++ b/drivers/iommu/mtk_iommu.c
> @@ -187,8 +187,7 @@ static void mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size,
> writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
> writel_relaxed(iova + size - 1,
> data->base + REG_MMU_INVLD_END_A);
> - writel_relaxed(F_MMU_INV_RANGE,
> - data->base + REG_MMU_INVALIDATE);
> + writel(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
>
> /* tlb sync */
> ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-10-14 14:04 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-14 6:38 [PATCH v3 0/7] Improve tlb range flush Yong Wu
2019-10-14 6:38 ` [PATCH v3 1/7] iommu/mediatek: Correct the flush_iotlb_all callback Yong Wu
2019-10-14 14:06 ` Robin Murphy
2019-10-14 6:38 ` [PATCH v3 2/7] iommu/mediatek: Add pgtlock in the iotlb_sync Yong Wu
2019-10-14 6:38 ` [PATCH v3 3/7] iommu/mediatek: Use gather to achieve the tlb range flush Yong Wu
2019-10-14 14:21 ` Robin Murphy
2019-10-15 5:26 ` Yong Wu
2019-10-15 11:38 ` Robin Murphy
2019-10-14 6:38 ` [PATCH v3 4/7] iommu/mediatek: Delete the leaf in the tlb flush Yong Wu
2019-10-14 14:22 ` Robin Murphy
2019-10-15 5:25 ` Yong Wu
2019-10-15 11:24 ` Robin Murphy
2019-10-14 6:38 ` [PATCH v3 5/7] iommu/mediatek: Move the tlb_sync into tlb_flush Yong Wu
2019-10-14 6:38 ` [PATCH v3 6/7] iommu/mediatek: Use writel for TLB range invalidation Yong Wu
2019-10-14 14:04 ` Robin Murphy [this message]
2019-10-15 5:25 ` Yong Wu
2019-10-14 6:38 ` [PATCH v3 7/7] iommu/mediatek: Reduce the tlb flush timeout value Yong Wu
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=c87e2a9c-5ed3-e44c-3b17-067db173eae9@arm.com \
--to=robin.murphy@arm.com \
--cc=anan.sun@mediatek.com \
--cc=chao.hao@mediatek.com \
--cc=cui.zhang@mediatek.com \
--cc=drinkcat@chromium.org \
--cc=edison.hsieh@mediatek.com \
--cc=evgreen@chromium.org \
--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=srv_heupstream@mediatek.com \
--cc=tfiga@google.com \
--cc=will.deacon@arm.com \
--cc=yong.wu@mediatek.com \
--cc=youlin.pei@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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).