Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1628081 > unrolled thread

Re: [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable Mark Rutland <mark.rutland@arm.com> - 2017-04-21 11:30 +0200

#1628081 — Re: [PATCH 3/3] bus: fsl-mc: dpio: change CENA regs to be cacheable

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

[toc] | [standalone]

Back to top | Article view | linux.kernel

csiph-web