On Thursday 17 February 2022 12:42:58 Stefan Roese wrote:
> On 2/17/22 12:37, Pali Rohár wrote:
> > On Thursday 17 February 2022 01:08:48 Marek Behún wrote:
> > > From: Marek Behún <marek.be...@nic.cz>
> > >
> > > Some boards may occacionally fail DDR training. Currently we hang() in
> > > this case. Add an option that makes the board do an immediate reset in
> > > such a case, so that a new training is tried as soon as possible,
> > > instead of hanging and possibly waiting for watchdog to reset the board.
> > >
> > > Signed-off-by: Marek Behún <marek.be...@nic.cz>
> > > Reviewed-by: Stefan Roese <s...@denx.de>
> > > ---
> > > arch/arm/mach-mvebu/Kconfig | 9 +++++++++
> > > arch/arm/mach-mvebu/spl.c | 6 +++++-
> > > 2 files changed, 14 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
> > > index d23cc0c760..ed957be6e1 100644
> > > --- a/arch/arm/mach-mvebu/Kconfig
> > > +++ b/arch/arm/mach-mvebu/Kconfig
> > > @@ -213,6 +213,15 @@ config DDR_LOG_LEVEL
> > > At level 3, rovides the windows margin of each DQ as a
> > > results of
> > > DQS centeralization.
> > > +config DDR_RESET_ON_TRAINING_FAILURE
> > > + bool "Reset the board on DDR training failure instead of hanging"
> > > + depends on ARMADA_38X || ARMADA_XP
> > > + help
> > > + If DDR training fails in SPL, reset the board instead of hanging.
> > > + Some boards are known to fail DDR training occasionally and an
> > > + immediate reset may be preferable to waiting until the board is
> > > + reset by watchdog (if there even is one).
> > > +
> > > config SYS_BOARD
> > > default "clearfog" if TARGET_CLEARFOG
> > > default "helios4" if TARGET_HELIOS4
> > > diff --git a/arch/arm/mach-mvebu/spl.c b/arch/arm/mach-mvebu/spl.c
> > > index 273ecb8bd6..d3c3bdc74d 100644
> > > --- a/arch/arm/mach-mvebu/spl.c
> > > +++ b/arch/arm/mach-mvebu/spl.c
> > > @@ -4,6 +4,7 @@
> > > */
> > > #include <common.h>
> > > +#include <cpu_func.h>
> > > #include <dm.h>
> > > #include <fdtdec.h>
> > > #include <hang.h>
> > > @@ -330,7 +331,10 @@ void board_init_f(ulong dummy)
> > > ret = ddr3_init();
> > > if (ret) {
> > > printf("ddr3_init() failed: %d\n", ret);
> > > - hang();
> > > + if (IS_ENABLED(CONFIG_DDR_RESET_ON_TRAINING_FAILURE))
> > > + reset_cpu();
> >
> > You should not call reset_cpu() from SPL loaded via UART. This will
> > confuse x-modem software. Either return failure to BootROM or hang()
> > like it was before.
>
> I see that this might confuse the kwboot / x-modem use-case. But AFAIU,
> this is more targeted to the normal use-case, that the board boots from
> SPI NOR (etc).
But kwb image is universal for both UART and SPI booting. So it target
both use cases.
> And here, a complete re-start could be helpful to at
> least get the board up and running after a few retries.
Of course, for SPI boot source it is required.
> Or am I missing something?
Just reset_cpu() call should be skipped when SPL is loaded via UART.
> Thanks,
> Stefan
