Ed Swierk eswierk@aristanetworks.com writes:
Anoyone familiar with the mcp55 who can shed some light on what this write is supposed to accomplish and perhaps also on why it succeeds using the IO config mechanism when mmconf fails?
That write has always caused a hang on Arista boards, even using plain IO accesses. I have no idea what it's supposed to do, but we've left it commented out with no apparent ill effects.
That's a valuable data point. I'm also running with it disabled, no apparent problems here either.
I'd like to push this mmconf patch upstream in some shape or form, so if anyone would like to chime in how to approach this I'd be glad. I could just wrap the offending line with "#if !CONFIG_MMCONF_SUPPORT_DEFAULT" or something, if that's acceptable. If we can't figure out what it affects, however, perhaps we're just as well off removing it?