All of lore.kernel.org
 help / color / mirror / Atom feed
From: mark.rutland@arm.com (Mark Rutland)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable
Date: Fri, 21 Apr 2017 10:27:06 +0100	[thread overview]
Message-ID: <20170421092706.GC6406@leverpostej> (raw)
In-Reply-To: <1492716858-24509-4-git-send-email-Haiying.Wang@nxp.com>

On Thu, Apr 20, 2017 at 03:34:18PM -0400, Haiying Wang wrote:
> plus non-shareable to meet the performance requirement.
> QMan's CENA region contains registers and structures that
> are 64byte in size and are inteneded to be accessed using a
> single 64 byte bus transaction, therefore this portal
> memory should be configured as cache-enabled. Also because
> the write allocate stash transcations of QBMan should be
> issued as cachable and non-coherent(non-sharable), we
> need to configure this region to be non-shareable.
> 
> Signed-off-by: Haiying Wang <Haiying.Wang@nxp.com>
> ---
>  drivers/staging/fsl-mc/bus/dpio/dpio-driver.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c b/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> index e36da20..97f909c 100644
> --- a/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> +++ b/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> @@ -168,10 +168,10 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
>  	desc.cpu = next_cpu;
>  
>  	/*
> -	 * Set the CENA regs to be the cache inhibited area of the portal to
> -	 * avoid coherency issues if a user migrates to another core.
> +	 * Set the CENA regs to be the cache enalbed area of the portal to
> +	 * archieve the best performance.

Is migrating to another core no longer a concern?

As with my prior comments regarding the Non-Shareable mapping, I do not
thing this makes sense.

Thanks,
Mark.

>  	 */
> -	desc.regs_cena = ioremap_wc(dpio_dev->regions[1].start,
> +	desc.regs_cena = ioremap_cache_ns(dpio_dev->regions[1].start,
>  		resource_size(&dpio_dev->regions[1]));
>  	desc.regs_cinh = ioremap(dpio_dev->regions[1].start,
>  		resource_size(&dpio_dev->regions[1]));
> -- 
> 2.7.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

WARNING: multiple messages have this Message-ID (diff)
From: Mark Rutland <mark.rutland@arm.com>
To: Haiying Wang <Haiying.Wang@nxp.com>
Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org,
	linux-arm-kernel@lists.infradead.org, roy.pledge@nxp.com,
	stuyoder@gmail.com
Subject: Re: [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable
Date: Fri, 21 Apr 2017 10:27:06 +0100	[thread overview]
Message-ID: <20170421092706.GC6406@leverpostej> (raw)
In-Reply-To: <1492716858-24509-4-git-send-email-Haiying.Wang@nxp.com>

On Thu, Apr 20, 2017 at 03:34:18PM -0400, Haiying Wang wrote:
> plus non-shareable to meet the performance requirement.
> QMan's CENA region contains registers and structures that
> are 64byte in size and are inteneded to be accessed using a
> single 64 byte bus transaction, therefore this portal
> memory should be configured as cache-enabled. Also because
> the write allocate stash transcations of QBMan should be
> issued as cachable and non-coherent(non-sharable), we
> need to configure this region to be non-shareable.
> 
> Signed-off-by: Haiying Wang <Haiying.Wang@nxp.com>
> ---
>  drivers/staging/fsl-mc/bus/dpio/dpio-driver.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c b/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> index e36da20..97f909c 100644
> --- a/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> +++ b/drivers/staging/fsl-mc/bus/dpio/dpio-driver.c
> @@ -168,10 +168,10 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
>  	desc.cpu = next_cpu;
>  
>  	/*
> -	 * Set the CENA regs to be the cache inhibited area of the portal to
> -	 * avoid coherency issues if a user migrates to another core.
> +	 * Set the CENA regs to be the cache enalbed area of the portal to
> +	 * archieve the best performance.

Is migrating to another core no longer a concern?

As with my prior comments regarding the Non-Shareable mapping, I do not
thing this makes sense.

Thanks,
Mark.

>  	 */
> -	desc.regs_cena = ioremap_wc(dpio_dev->regions[1].start,
> +	desc.regs_cena = ioremap_cache_ns(dpio_dev->regions[1].start,
>  		resource_size(&dpio_dev->regions[1]));
>  	desc.regs_cinh = ioremap(dpio_dev->regions[1].start,
>  		resource_size(&dpio_dev->regions[1]));
> -- 
> 2.7.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2017-04-21  9:27 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-20 19:34 [PATCH 0/3] bus: fsl-mc: dpio: udpate QMan CENA region Haiying Wang
2017-04-20 19:34 ` Haiying Wang
2017-04-20 19:34 ` [PATCH 1/3] arm64: extend ioremap for cacheable non-shareable memory Haiying Wang
2017-04-20 19:34   ` Haiying Wang
2017-04-21  9:11   ` Mark Rutland
2017-04-21  9:11     ` Mark Rutland
2017-04-21 14:30     ` Roy Pledge
2017-04-21 14:30       ` Roy Pledge
2017-04-25 13:42       ` Mark Rutland
2017-04-25 13:42         ` Mark Rutland
2017-04-20 19:34 ` [PATCH 2/3] bus: fsl-mc: dpio: enable qbman CENA portal memory access Haiying Wang
2017-04-20 19:34   ` Haiying Wang
2017-04-21  9:25   ` Mark Rutland
2017-04-21  9:25     ` Mark Rutland
2017-04-21 14:37   ` Catalin Marinas
2017-04-21 14:37     ` Catalin Marinas
2017-04-20 19:34 ` [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable Haiying Wang
2017-04-20 19:34   ` Haiying Wang
2017-04-21  9:27   ` Mark Rutland [this message]
2017-04-21  9:27     ` Mark Rutland

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=20170421092706.GC6406@leverpostej \
    --to=mark.rutland@arm.com \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.