Use of fdt_parent_offset() is very expensive as detailed by the function documentation:
NOTE: This function is expensive, as it must scan the device tree structure from the start to nodeoffset, *twice*. This series remove multiple calls to fdt_parent_offset() or ofnode_get_parent() when instead a single call can be made and the returned value can be reused. This series help reduce boot time by around: - ~137ms on a Radxa ROCK Pi 4 (RK3399) - ~33ms on a Radxa ZERO 3W (RK3566) Jonas Karlman (3): dm: core: fdtaddr: Avoid multiple calls to fdt_parent_offset() dm: core: ofnode: Avoid multiple calls to ofnode_get_parent() dm: core: regmap: Avoid multiple calls to ofnode_get_parent() drivers/core/fdtaddr.c | 24 +++++++++++++++++------- drivers/core/ofnode.c | 5 +++-- drivers/core/regmap.c | 14 ++++++++++---- 3 files changed, 30 insertions(+), 13 deletions(-) -- 2.45.2
