linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: tixy@linaro.org (Jon Medhurst (Tixy))
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] arm64: dts: juno: Enable some SMMUs
Date: Thu, 18 May 2017 14:13:59 +0100	[thread overview]
Message-ID: <1495113239.3174.11.camel@linaro.org> (raw)
In-Reply-To: <eeb81dbbd7ddfbbccb961c0f20c5cb90f120e89f.1495110010.git.robin.murphy@arm.com>

On Thu, 2017-05-18 at 13:23 +0100, Robin Murphy wrote:
> The IOMMU-backed DMA API support has now been in place for a while and
> proven stable, so there's no real need to keep most of Juno's SMMUs
> disabled. The USB, HDLCDs, and CoreSight ETR all just need to map RAM
> buffers for DMA - enabling their SMMUs obviates CPU bounce buffering for
> USB's streaming DMA to the upper memory bank, and lets the other two
> allocate their relatively large coherent buffers without pressuring CMA.
> 
> Some more software work is still needed for the DMA-330 and PCIe before
> those can accommodate SMMU translation correctly in all cases, so we
> leave those alone for now.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---

For those that don't already know, status = "disabled" for smmu is
broken in Linux 4.12-rc1, and this fixes it...
https://lkml.org/lkml/2017/5/17/344

>  arch/arm64/boot/dts/arm/juno-base.dtsi | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi b/arch/arm64/boot/dts/arm/juno-base.dtsi
> index bfe7d683a42e..02aea43238fc 100644
> --- a/arch/arm64/boot/dts/arm/juno-base.dtsi
> +++ b/arch/arm64/boot/dts/arm/juno-base.dtsi
> @@ -53,7 +53,6 @@
>  		#global-interrupts = <1>;
>  		dma-coherent;
>  		power-domains = <&scpi_devpd 0>;
> -		status = "disabled";
>  	};
>  
>  	gic: interrupt-controller at 2c010000 {
> @@ -546,7 +545,6 @@
>  			     <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>;
>  		#iommu-cells = <1>;
>  		#global-interrupts = <1>;
> -		status = "disabled";
>  	};
>  
>  	smmu_hdlcd0: iommu at 7fb20000 {
> @@ -556,7 +554,6 @@
>  			     <GIC_SPI 97 IRQ_TYPE_LEVEL_HIGH>;
>  		#iommu-cells = <1>;
>  		#global-interrupts = <1>;
> -		status = "disabled";
>  	};
>  
>  	smmu_usb: iommu at 7fb30000 {
> @@ -567,7 +564,6 @@
>  		#iommu-cells = <1>;
>  		#global-interrupts = <1>;
>  		dma-coherent;
> -		status = "disabled";
>  	};
>  
>  	dma at 7ff00000 {

  reply	other threads:[~2017-05-18 13:13 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-18 12:23 [PATCH] arm64: dts: juno: Enable some SMMUs Robin Murphy
2017-05-18 13:13 ` Jon Medhurst (Tixy) [this message]
2017-05-18 13:20   ` Liviu Dudau
2017-05-18 14:30   ` Robin Murphy
2017-05-18 13:21 ` Liviu Dudau
2017-05-19 17:42 ` Sudeep Holla
2017-06-06 15:45 ` Jean-Philippe Brucker
2017-06-06 15:59   ` Robin Murphy
2017-06-06 16:16     ` Jean-Philippe Brucker

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=1495113239.3174.11.camel@linaro.org \
    --to=tixy@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.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;
as well as URLs for NNTP newsgroup(s).