The two principal manufacturers of Apple processors, Samsung and TSMC, have each begun volume production of the next-generation "A9" CPU for use in the upcoming iPhones, according to a new report.

TSMC however is only expected to enter mass production in the fourth quarter of 2015, using its 16-nanometer FinFET process, industry sources told DigiTimes. If Apple holds to a standard September iPhone launch window, that would imply that TSMC will not make a meaningful contribution to launch-day iPhones, at least in terms of CPUs.

The company is reportedly also doing contract production of Touch ID sensors and audio chips for the new iPhones, the latter on behalf of Cirrus Logic.

The sources added that estimates call for 80 million new iPhones to be shipped by the end of the year. That would be well below the 85 to 90 million recently claimed by The Wall Street Journal.