[PATCH v4 1/4] imx9: Add support for saving DDR training data to NVM

[Francesco Dolcini]

Hello Simona,

On Wed, Jun 03, 2026 at 09:24:07AM +0200, Francesco Dolcini wrote:
> Hello Simona,
> 
> On Tue, Jun 02, 2026 at 01:59:39PM +0300, Simona Toaca wrote:
> > On Thu, May 28, 2026 at 10:55:23AM +0530, Kumar, Udit wrote:
> > > On 4/30/2026 2:03 PM, Simona Toaca (OSS) wrote:
> > > > From: Simona Toaca <simona.toaca at nxp.com>
> > > > 
> > > > DDR training data can be saved to NVM and be available
> > > > to OEI at boot time, which will trigger QuickBoot flow.
> > > > 
> > > > U-Boot only checks for data integrity (CRC32), while
> > > > OEI is in charge of authentication when it tries to
> > > > load the data from NVM.
> > > > 
> > > >  
> > [...]
> > > > +#define DDRPHY_QB_PSTATES	0
> > > > +#define DDRPHY_QB_PST_SIZE	(DDRPHY_QB_PSTATES * 4 * 1024)
> > > 
> > > [..]
> > > Sorry for basic question, in case OEI layer changes format due to one of
> > > other reason then how you are making sure, struct ddrphy_qb_state is
> > > aligned
> > > 
> > > + * This structure needs to be aligned with the one in OEI.
> > > 
> > For now, the structure is stable. If anything changes, I will take care
> > to update U-Boot accordingly.
> 
> Did you consider Emanuele's email in which he thinks that what we have today
> should already be changed? 

Following up on this, we moved on with a different approach that does
not require changing this data structure.

You can have a look at our implementation here, https://git.toradex.com/imx-oei-toradex.git/,
if you are interested.

Francesco