Cruise Automation, GM's subsidiary focused on making autonomous vehicles, will get a big cash infusion this year, as SoftBank Vision Fund will invest $2.25 billion in it.

"This is a very historic day when we look at the future of personal mobility. We are pleased to partner with Softbank," Mary Barra, GM CEO, said. "We're 100 percent committed to this mission and creating safe autonomous vehicles at large scale."

Softbank Vision Fund is a prominent tech investment firm based in Tokyo, and the deal gives them a nearly 20% stake in GM Cruise.

"GM has made significant progress toward realizing the dream of completely automated driving to dramatically reduce fatalities, emissions and congestion," said Michael Ronen, managing partner, SoftBank Investment Advisers. "The GM Cruise approach of a fully integrated hardware and software stack gives it a unique competitive advantage. We are very impressed by the advances made by the Cruise and GM teams, and are thrilled to help them lead a historic transformation of the automobile industry."

The deal is contingent on GM committing $1.1 billion of its own money to Cruise Automation. GM had already planned on investing that much, though, and has already funneled $500 million into the subsidiary this year.

SoftBank's money will come in two installments. First, Cruise Automation will receive $900 million and the rest will be handed over when the vehicles are ready for commercial deployment.