Non-Japanese with resident visa, flying to Shanghai. Do I need to appy for my Shanghai visit?

Hi there, I'm a Canadian, living in Japan with a Japan resident type one. I Need to fly to Shanghai for 5 days of business. My co-workers in the Shanghai office prepared a "letter of invitation" for me. Do I need still need to apply from the Chineses embassy in Tokyo? How long does it take to get it?

Thanks for your help!!