From: "Jernej Škrabec" <jernej.skrabec@gmail.com>
To: Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
iommu@lists.linux-foundation.org,
Samuel Holland <samuel@sholland.org>
Cc: Heiko Stuebner <heiko@sntech.de>,
Palmer Dabbelt <palmer@dabbelt.com>,
linux-riscv@lists.infradead.org,
Samuel Holland <samuel@sholland.org>,
Chen-Yu Tsai <wens@csie.org>,
Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
Maxime Ripard <mripard@kernel.org>,
Philipp Zabel <p.zabel@pengutronix.de>,
Rob Herring <robh+dt@kernel.org>,
devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, linux-sunxi@lists.linux.dev
Subject: Re: [PATCH 3/5] iommu/sun50i: Ensure bypass is disabled
Date: Thu, 28 Apr 2022 07:43:25 +0200 [thread overview]
Message-ID: <1922960.8hb0ThOEGa@jernej-laptop> (raw)
In-Reply-To: <20220428010401.11323-4-samuel@sholland.org>
Dne četrtek, 28. april 2022 ob 03:03:58 CEST je Samuel Holland napisal(a):
> The H6 variant of the hardware disables bypass by default. The D1
> variant of the hardware enables bypass for all masters by default.
>
> Since the driver expects bypass to be disabled, ensure that is the case.
>
> Signed-off-by: Samuel Holland <samuel@sholland.org>
Actually, it would be better to set bypass to 0xff and in
sun50i_iommu_attach_device() clear bypass bit for that particular device. As
you might notice, index in phandle is currently not used. This would also help
expose bugs, like missing second iommu channel for Cedrus on H6, but that's
easy to fix.
Best regards,
Jernej
> ---
>
> drivers/iommu/sun50i-iommu.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c
> index ec07b60016d3..b9e644b93637 100644
> --- a/drivers/iommu/sun50i-iommu.c
> +++ b/drivers/iommu/sun50i-iommu.c
> @@ -374,6 +374,8 @@ static int sun50i_iommu_enable(struct sun50i_iommu
> *iommu)
>
> spin_lock_irqsave(&iommu->iommu_lock, flags);
>
> + iommu_write(iommu, IOMMU_BYPASS_REG, 0);
> +
> iommu_write(iommu, IOMMU_TTB_REG, sun50i_domain->dt_dma);
> iommu_write(iommu, IOMMU_TLB_PREFETCH_REG,
> IOMMU_TLB_PREFETCH_MASTER_ENABLE(0) |
_______________________________________________
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:[~2022-04-28 5:44 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-28 1:03 [PATCH 0/5] iommu/sun50i: Allwinner D1 support Samuel Holland
2022-04-28 1:03 ` [PATCH 1/5] dt-bindings: iommu: sun50i: Add compatible for Allwinner D1 Samuel Holland
2022-04-28 7:19 ` Krzysztof Kozlowski
2022-04-28 1:03 ` [PATCH 2/5] iommu/sun50i: Support variants without an external reset Samuel Holland
2022-04-28 5:34 ` Jernej Škrabec
2022-04-28 7:43 ` Philipp Zabel
2022-04-28 1:03 ` [PATCH 3/5] iommu/sun50i: Ensure bypass is disabled Samuel Holland
2022-04-28 5:43 ` Jernej Škrabec [this message]
2022-04-28 1:03 ` [PATCH 4/5] iommu/sun50i: Add support for the D1 variant Samuel Holland
2022-04-28 5:34 ` Jernej Škrabec
2022-04-28 1:04 ` [PATCH 5/5] iommu/sun50i: Ensure the IOMMU can be used for DMA Samuel Holland
2022-04-28 5:35 ` Jernej Škrabec
2022-04-28 11:12 ` Robin Murphy
2022-04-28 5:45 ` [PATCH 0/5] iommu/sun50i: Allwinner D1 support Jernej Škrabec
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=1922960.8hb0ThOEGa@jernej-laptop \
--to=jernej.skrabec@gmail.com \
--cc=devicetree@vger.kernel.org \
--cc=heiko@sntech.de \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=linux-sunxi@lists.linux.dev \
--cc=mripard@kernel.org \
--cc=p.zabel@pengutronix.de \
--cc=palmer@dabbelt.com \
--cc=robh+dt@kernel.org \
--cc=samuel@sholland.org \
--cc=wens@csie.org \
--cc=will@kernel.org \
/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