Reference in a new issue

Blame

Copy permalink

Reference in a new issue

Copy permalink

Claudiu Beznea 7efca37d31 ARM: at91: pm: fix DDR recalibration when resuming from backup and self-refresh ... [ Upstream commit 7a94b83a7d ] On SAMA7G5, when resuming from backup and self-refresh, the bootloader performs DDR PHY recalibration by restoring the value of ZQ0SR0 (stored in RAM by Linux before going to backup and self-refresh). It has been discovered that the current procedure doesn't work for all possible values that might go to ZQ0SR0 due to hardware bug. The workaround to this is to avoid storing some values in ZQ0SR0. Thus Linux will read the ZQ0SR0 register and cache its value in RAM after processing it (using modified_gray_code array). The bootloader will restore the processed value. Fixes: d2d4716d83 ("ARM: at91: pm: save ddr phy calibration data to securam") Suggested-by: Frederic Schumacher <frederic.schumacher@microchip.com> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20220826083927.3107272-4-claudiu.beznea@microchip.com Signed-off-by: Sasha Levin <sashal@kernel.org>		History 2022-09-15 10:47:14 +02:00
..
at91sam9_ddrsdr.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
at91sam9_sdramc.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
atmel-secumod.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
atmel-sfr.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
atmel_tcb.h	ARM: at91: add atmel tcb capabilities	2020-07-11 18:57:03 +02:00
pm.h	ARM: at91: pm: Move prototypes to mutually included header	2021-03-26 18:20:49 +01:00
sama7-ddr.h	ARM: at91: pm: fix DDR recalibration when resuming from backup and self-refresh	2022-09-15 10:47:14 +02:00
sama7-sfrbu.h	ARM: at91: sfrbu: add sfrbu registers definitions for sama7g5	2021-07-19 14:32:12 +02:00