On Mon, Oct 06, 2008 at 07:12:41PM +1100, Finn Thain wrote:
I haven't submitted this with sign-off because I'm not actually sure that a VBL interrupt is desirable. It adds overhead and I don't think I've seen any problems from the cursor timer on macs (are there any?). Perhaps we should just rip out the mac VBL code instead of fixing it?
I think we should forget about this. The interrupt in question on the Mac isn't really tied to the video at all. It's only called a VBL interrupt for historical reasons. In fact, it relies on VIA2 being setup correctly on some models. Apple added it to emulate the behavior of the original Macintosh where that line really was tied to the video circuits, but in later models it's tied to the output of one of the timers in VIA2 or generated inside RBV. We should either use an interrupt actually generated by the video on each machine or just use a timer, since this interrupt is really just a timer anyway. Brad Boyer flar@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
