On Thu Jun 25, 2026 at 3:21 AM CDT, Anshul Dalal wrote: > On Thu Jun 25, 2026 at 4:59 AM IST, Randolph Sapp wrote: >> On Wed Jun 24, 2026 at 4:19 PM CDT, rs wrote: >>> From: Randolph Sapp <[email protected]> >>> >>> Take Phytec's current DDR fixup functions and utilize them to >>> dynamically adjust for variants in the pocketbeagle2. There are >>> currently 3 skews, two of which are both 512MB with the same memory >>> configuration, and one which is 1GB using the same CWL and CL settings >>> but a modified density [1]. >>> >>> Based off of Bryan Brattlof's patch [2]. >>> >>> [1] >>> https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/5411/8G%20Bits%20DDR4%20SDRAM.pdf >>> [2] >>> https://github.com/bryanbrattlof/beagleboot/commit/fb2f022e27427e990d7a33fd001ffb571e13cfc3 >>> >>> Signed-off-by: Randolph Sapp <[email protected]> >>> --- >>> board/beagle/pocketbeagle2/Kconfig | 26 +++++ >>> board/beagle/pocketbeagle2/Makefile | 2 + >>> board/beagle/pocketbeagle2/pocketbeagle2.c | 103 +++++++++++++++++- >>> .../beagle/pocketbeagle2/pocketbeagle2_ddr.h | 50 +++++++++ >>> configs/am62_pocketbeagle2_r5_defconfig | 5 +- >>> 5 files changed, 184 insertions(+), 2 deletions(-) >>> create mode 100644 board/beagle/pocketbeagle2/pocketbeagle2_ddr.h >>> >>> [snip] >> >> Just thinking out loud here, but maybe we shouldn't take this patch. The >> industrial version, on top of having more memory, also has eMMC. That already >> mandates a new device tree and configuration if people are going to use it >> as a >> boot method. >> >> Then again, maybe it's convenient for the users who don't care about eMMC? I >> dunno. Seems odd either way. > > Since it's technically a different board altogether and not just PB2 w/ > extra DDR. I think it might be better if it had a separate DT and we can > decide the correct one based on the EEPROM at runtime using > SPL_MULTI_DTB_FIT which would allow us to still have a single defconfig > in U-Boot.
Syncing some internal comments here: Zephyr and Jason Kridner apparently agree with me here. They treat the device as a separate model: https://github.com/zephyrproject-rtos/zephyr/pull/106680 To cite Bryan Brattlof: I don't think the R5 has the space to switch-out the DT like this during bootup. it would need to be another build Sounds like we'll have to upstream a separate dt and defconfig then. I'll play around with this a little on my end before submitting another revision. Suppose the dt will have to go to the kernel first so it'll be a little bit.
