I think your response is not correct. The ASM instance will require a parameter file, just like any other Oracle instance. As of 11gR2, the ASM spfile is stored automatically in the first disk group created during the Grid Infrastructure installation.
The trick is that ASM can read the spfile stored on ASM disks through the css cluster daemon and reading the ASM device header. People here in the forum and on the Internet have written good and detailed information about this, for instance:
Where is my Oracle ASM Instance spfile