[U-Boot] [PATCHv2] block: Have BLOCK_CACHE default to y in some cases

[Adam Ford]

On Fri, Jun 8, 2018 at 2:15 PM Tom Rini <trini at konsulko.com> wrote:
>
> On Fri, Jun 08, 2018 at 10:30:36AM -0500, Adam Ford wrote:
> > On Tue, May 22, 2018 at 11:24 AM Tom Rini <trini at konsulko.com> wrote:
> > >
> > > When dealing with filesystems that come from block devices we can get a
> > > noticeable performance gain in some use cases from having the block
> > > cache enabled.  The code paths are valid in other cases when we have BLK
> > > set and may provide wins in raw reads in some use cases, so have this be
> > > default when BLK is enabled.
> > >
> > Tony,
> >
> > This breaks the AM3517 EVM. It appears to cause issues in MLO which
> > may not have enough RAM to cache, but I can fix it by disabling
> > BLOCK_CACHE.
> > I can submit a patch to disable it on the AM3517, but I am wondering
> > if something can/should be done to disable it or optionally disable it
> > in SPL so it's still
> > available in U-Boot.  I can confirm that when disabled in SPL only, it works.
> >
> > Any opinions on this?
>
> So, we had talked before about bumping SYS_MALLOC_F_LEN to 0x2000 for
> ARCH_OMAP2PLUS, but I see am3517 is already doing that.  Can you see if
> there's enough room to go to say 0x4000 and it works?  Otherwise, we

I tried setting it to 0x4000, but it just hangs:

U-Boot SPL 2018.07-rc1-00040-g71002b508a (Jun 08 2018 - 15:16:44 -0500)
Trying to boot from MMC1

> need to (and I was worried we might) need to add SPL_BLOCK_CACHE and
> have that default off.  Thanks!

Do you want me to work on that patch or did you want to do it?

adam
>
> --
> Tom