On 5/25/23 10:08, Patrick DELAUNAY wrote:
Hi Marek,
Hello Patrick,
sorry for the abysmal delay.
On 5/18/23 00:02, Marek Vasut wrote:
In case the DHSOM is in suspend state and either reset button is pushed
or IWDG2 triggers a watchdog reset, then DRAM initialization could fail
as follows:
"
RAM: DDR3L 32bits 2x4Gb 533MHz
DDR invalid size : 0x4, expected 0x40000000
DRAM init failed: -22
### ERROR ### Please RESET the board ###
"
Avoid this failure by not keeping any Buck regulators enabled during
reset,
let the SoC and DRAMs power cycle fully. Since the change which keeps
Buck3
VDD enabled during reset is ST specific, move this addition to ST
specific
SPL board initialization so that it wouldn't affect the DHSOM .
Signed-off-by: Marek Vasut <[email protected]>
---
NOTE: This is 2023.07 material
NOTE: d1a4b09de64 ("board: st: stpmic1: add function stpmic1_init")
mentions 'keep vdd on during the reset cycle (to avoid issue
when backup battery is absent)', but there is no further
description of the 'issue'. Can you please elaborate ?
In the commit message of d1a4b09de643 ("board: st: stpmic1:
add function stpmic1_init"), I indicated
- keep vdd on during the reset cycle (to avoid issue when backup battery
is absent)
On ST boards we have support of cell coin to allow support of backup
domain,
but by default this cell are absent and the backup domain is directly
powered
by VDD (directly connected by resistor).
We keep powered this domain to don't loss the backup domain support,
to avoid to loss the information saved in backup RAM / registers,
and to be abble to keep DEBUG part powered also.
On this ST board, if the VDD is shut down with reset, the backup domain
can't be
correctly managed for reboot.
And to handle correctly power OFF on ST boards with PMIC, we will don't
shut down
the VDD (full PMIC shut down) but we keep it.
So the backup domain is loosed on ST board with STPMIC1 only when the power
is removed and not for reset or for power off.
Thank you for the clarification.
I should check suspend/resume on EV1 soon ...
