From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <3B95A796.248A0E99@mvista.com> Date: Wed, 05 Sep 2001 00:18:30 -0400 From: Dan Malek MIME-Version: 1.0 To: David Gibson Cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: 4xx - a question and a patch References: <20010830175217.H858@zax> <3B95307D.1BE64A98@mvista.com> <20010905110451.A599@zax> Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: David Gibson wrote: > The 405gp manual implies that an mtspr to the PIT writes both the > decrementing value and the reload register. Is this a hardware / > documentation bug? Well, the point is that it writes the reload register. When it gets to zero, it reloads with this register, which is wrong. > ..... Could the PIT be used this way if auto-reload was > disabled? No, because the PIT doesn't count down past zero. If they would have allowed this, we could have disabled the auto-reload and treated it just like the decrementer. The best I could come up with is just allow the PIT run with a proper and fixed reload value. It isn't a decrementer and we can't treat it like one. > Sure, but it's still useful to be able to run binaries copied from > "normal" PPC machines. Just remember that you can't be mixing float emulation and in-line floating point software. -- Dan ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/