[PATCH u-boot-mvebu 10/10] arm: mvebu: turris_omnia: Support old DDR3 training, selectable via env var

[Marek Behún]

On Wed, 15 May 2024 11:10:09 +0200
Stefan Roese <sr at denx.de> wrote:

> Hi Marek,
> 
> On 5/15/24 10:59, Marek Behún wrote:
> > On Mon, 6 May 2024 12:03:55 +0200
> > Stefan Roese <sr at denx.de> wrote:
> >   
> >> Hi Marek,
> >>
> >> On 4/15/24 18:30, Marek Behún wrote:  
> >>> Support old DDR3 training code on Turris Omnia, selectable by U-Boot
> >>> enviroment variable.
> >>>
> >>> Users experiencing DDR3 initialization failures or random crashes of the
> >>> operating system due to incorrect DDR3 configuration can select the old
> >>> DDR3 training implementation to fix those issues by setting the
> >>> environment variable
> >>>     env set omnia_ddr3_training old
> >>>     env save
> >>>
> >>> Signed-off-by: Marek Behún <kabel at kernel.org>
> >>> ---
> >>>    arch/arm/mach-mvebu/Kconfig                   |  1 +
> >>>    board/CZ.NIC/turris_omnia/Makefile            |  1 +
> >>>    board/CZ.NIC/turris_omnia/old_ddr3_training.c | 79 +++++++++++++++++++
> >>>    board/CZ.NIC/turris_omnia/turris_omnia.c      |  2 +-
> >>>    4 files changed, 82 insertions(+), 1 deletion(-)
> >>>    create mode 100644 board/CZ.NIC/turris_omnia/old_ddr3_training.c  
> >>
> >> For turris_omnia_defconfig, this is dropped when compiled:
> >>
> >> drivers/ddr/marvell/a38x/old/ddr3_debug.c:776:12: warning:
> >> 'ddr3_tip_access_atr' declared 'static' but never defined
> >> [-Wunused-function]
> >>     776 | static int ddr3_tip_access_atr(u32 dev_num, u32 flag_id, u32
> >> value, u32 **ptr);
> >>         |            ^~~~~~~~~~~~~~~~~~~  
> > 
> > And it also seems that there is still something wrong with this
> > old DDR training code port. Some boards still experience random bugs
> > with this, but not with the U-Boot from 2015. :-(  
> 
> Hmmm, strange.
> 
> How to continue? Are these "old DDR training patches" on hold for now?

The first 5 patches should be fine, the "old DDR training" comes in the
second half. Is it possible to merge only the first 5? And also the one
patch I sent on April 30:
  arm: mvebu: turris_omnia: Fix ethernet PHY reset gpio FDT fixup

Marek