[U-Boot] [PATCH v2 1/2] ARM: Move SYS_CACHELINE_SIZE over to Kconfig

Tom Rini trini at konsulko.com
Mon Aug 22 15:39:02 CEST 2016


On Mon, Aug 22, 2016 at 09:24:04PM +0800, Chin Liang See wrote:
> Hi Tom,
> 
> On Mon, 2016-08-22 at 08:22 -0400, Tom Rini wrote:
> > This series moves the CONFIG_SYS_CACHELINE_SIZE.  First, in nearly
> > all
> > cases we are mirroring the values used by the Linux Kernel here. 
> >  Also,
> > so long as (and in this case, it is true) we implement flushes in
> > hunks
> > that are no larger than the smallest implementation (and given that
> > we
> > mirror the Linux Kernel, again we are fine) it is OK to align higher.
> > The biggest changes here are that we always use 64 bytes for CPU_V7
> > even
> > if for example the underlying core is only 32 bytes (this mirrors
> > Linux).  Second, we say ARM64 uses 64 bytes not 128 (as found in the
> > Linux Kernel) as we do not need multi-platform support (to this
> > degree)
> > and only the Cavium ThunderX 88xx series has a use for such large
> > alignment.
> > 
> > 
> ...
> 
> >  arch/arm/Kconfig                                  | 27
> 
> > ... 
> 
> > 
> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > index aef901c3f448..e6d4a2043854 100644
> > --- a/arch/arm/Kconfig
> > +++ b/arch/arm/Kconfig
> > @@ -7,6 +7,7 @@ config SYS_ARCH
> > 
> 
> ...
> 
> >  
> >  config CPU_V7
> >          bool
> >          select HAS_VBAR
> >          select HAS_THUMB2
> > +	select SYS_CACHE_SHIFT_6
> >  
> 
> CPU_V7 should use SYS_CACHE_SHIFT_5 which is 32 bytes cache lines.

No, some V7 are 32 and some are 64, for example Cortex-A8.

-- 
Tom
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: Digital signature
URL: <http://lists.denx.de/pipermail/u-boot/attachments/20160822/23b00404/attachment.sig>


More information about the U-Boot mailing list