ARM: at91: pm: fix self-refresh for sama7g5
[ Upstream commit a02875c4 ] It has been discovered that on some parts, from time to time, self-refresh procedure doesn't work as expected. Debugging and investigating it proved that disabling AC DLL introduce glitches in RAM controllers which leads to unexpected behavior. This is confirmed as a hardware bug. DLL bypass disables 3 DLLs: 2 DX DLLs and AC DLL. Thus, keep only DX DLLs disabled. This introduce 6mA extra current consumption on VDDCORE when switching to any ULP mode or standby mode but the self-refresh procedure still works. Fixes: f0bbf179 ("ARM: at91: pm: add self-refresh support for sama7g5") Suggested-by: Frederic Schumacher <frederic.schumacher@microchip.com> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Tested-by: Cristian Birsan <cristian.birsan@microchip.com> Link: https://lore.kernel.org/r/20220826083927.3107272-3-claudiu.beznea@microchip.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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