2010/4/2 Blue Swirl <blauwir...@gmail.com>: > On 4/1/10, Artyom Tarasenko <atar4q...@googlemail.com> wrote: >> 2010/4/1 Blue Swirl <blauwir...@gmail.com>: >> > Which list? >> >> This mailing list? >> >> >> > On 4/1/10, Artyom Tarasenko <atar4q...@googlemail.com> wrote: >> >> and looks wrong or incomplete to me: >> >> >> >> >According to Sun4M System Architecture Manual chapter 5.3.2, a limit >> >> >of 0 will not generate interrupts. >> >> >> >> This is indeed correct, but the chapter 5.3.2 also explains why: >> >> >> >> "Setting the limit register to 0 allows the counter to free run. >> Since the >> >> timer always resets to a value of 500 nS after reaching maximum count, >> >> there is no match and no interrupts are generated." >> >> >> >> The part about 500 nS (0x00000200 in the counter register) and >> >> no match seems to be not addressed. >> > >> > The 500ns offset part could be addressed by making the timer period >> > shorter by 1 tick. I doubt such a change would have any visible >> > difference with QEMU, except that tick count of 0 should never appear >> > in the counter but it may now. >> >> >> as well as all the other values between 0 and 0x200. But it's less >> important I guess. >> >> >> > For the no match part, t->reached should not be set if t->limit == 0. > > I think this patch would do what is expected.
Looks good and passes my tests, thanks. Redefining LIMIT_TO_PERIODS is a really nice solution. -- Regards, Artyom Tarasenko solaris/sparc32 under qemu blog: http://tyom.blogspot.com/
