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Overflow interrupts, on hardware that supports them could > be used to remove this limitation. > > Cc: Zeng Heng > Reviewed-by: Gavin Shan > Reviewed-by: Zeng Heng > Reviewed-by: Jonathan Cameron > Tested-by: Carl Worth > Tested-by: Gavin Shan > Tested-by: Zeng Heng > Signed-off-by: Ben Horgan Reviewed-by: Fenghua Yu Thanks. -Fenghua