Re: [PATCH v2] board: kontron: increase the CONFIG_SYS_MALLOC_F_LEN

[Tom Rini <trini@konsulko.com>]

[-- Attachment #1: Type: text/plain, Size: 2854 bytes --]

On Wed, Mar 23, 2022 at 02:33:12PM -0400, Sean Anderson wrote:
> On 3/23/22 2:26 PM, Heiko Thiery wrote:
> > Hi Simon,
> > 
> > Am Mi., 23. März 2022 um 19:04 Uhr schrieb Simon Glass <sjg@chromium.org>:
> > > 
> > > Hi Heinrich,
> > > 
> > > On Tue, 22 Mar 2022 at 03:25, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote:
> > > > 
> > > > On 3/21/22 15:26, Heiko Thiery wrote:
> > > > > It was observed that enabling additional DM modules the configured
> > > > > malloc value is not sufficient. So lets increase the value.
> > > > > 
> > > > > Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com>
> > > > > ---
> > > > > v2:
> > > > >    - add a more proper commit message to explan why the value was increased
> > > > > 
> > > > >    configs/kontron_pitx_imx8m_defconfig | 1 +
> > > > >    1 file changed, 1 insertion(+)
> > > > > 
> > > > > diff --git a/configs/kontron_pitx_imx8m_defconfig b/configs/kontron_pitx_imx8m_defconfig
> > > > > index 76430213e3..30c3586937 100644
> > > > > --- a/configs/kontron_pitx_imx8m_defconfig
> > > > > +++ b/configs/kontron_pitx_imx8m_defconfig
> > > > > @@ -2,6 +2,7 @@ CONFIG_ARM=y
> > > > >    CONFIG_ARCH_IMX8M=y
> > > > >    CONFIG_SYS_TEXT_BASE=0x40200000
> > > > >    CONFIG_SYS_MALLOC_LEN=0x600000
> > > > > +CONFIG_SYS_MALLOC_F_LEN=0x10000
> > > > 
> > > > @Heiko
> > > > Should we really adjust this on board level? Won't we have the same
> > > > problem on all imx8m boards?
> > > > 
> > > > Why don't you change the default for all i.mx8 boards in /Kconfig?
> > > > 
> > > > @Tom, @Simon
> > > > Shouldn't we replace the default of 0x400 by 0x2000 generally?
> > > 
> > > I don't think that is a good idea. That is a lot of memory! Many
> > > platforms don't need that much.
> > > 
> > > I wonder what is driving this large amount. Is it pinctrl?
> > 
> > The increase comes from the introduction of a clock driver for the
> > imx8mq platform.
> 
> Yes, the problem is that CCF creates a udevice+clk+private data for
> every clock. This runs about 150-200 bytes per clock on a 64-bit
> platform. In addition, many physical clocks are modeled as several
> logical clocks plus a composite. This means a platform with maybe
> 20-30 physical clocks can easily allocate 10k-20k to create
> the clock tree.

And to cycle back to what I mentioned on IRC at some point, I disagree
with the notion many platforms don't need "that" might.  Yes, 0x10000
tends to be on the higher end, but there's larger still boards, but we
should likely set a new default X if DM (and similar, default Y if
SPL_DM, and Z for TPL) and bump the boards up that are below that but
more than current default, to that default.  A value of 0x400 is
unreasonably small for DM and likely anything less than 0x4000 (what
sandbox picks) is going to be problematic.

-- 
Tom

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 659 bytes --]