From mboxrd@z Thu Jan 1 00:00:00 1970 In-Reply-To: Date: Tue, 16 Feb 1999 19:11:48 +0100 To: Gabriel Paubert , linuxppc-dev@lists.linuxppc.org From: Benjamin Herrenschmidt Subject: Re: bootstrap stuffs Message-Id: <19990216191148.002398@mail.mipsys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, Feb 16, 1999, Gabriel Paubert wrote: >So, if I'm not mistaken, a read from the same location is the only >operation that guarantees that the register has actually been updated, but >it's even slower than a sync :-( On a side note, there is an interesting implementation of interrupts in MkLinux mach kernel. Since they consider the controller as a really slow device (and this seems to be confirmed by the bogus interrupt we had on PowerMacs), they actually do it differently: Mach maintains the current interrupt mask locally in RAM. When it disables an interrupt, it does so only in the mask, the controller gets updated only if this interrupt actually occurs. The enable code will enable it in the mask only if it has been disabled by the interrupt. -- E-Mail: BenH. Web : [[ This message was sent via the linuxppc-dev mailing list. Replies are ]] [[ not forced back to the list, so be sure to Cc linuxppc-dev if your ]] [[ reply is of general interest. To unsubscribe from linuxppc-dev, send ]] [[ the message 'unsubscribe' to linuxppc-dev-request@lists.linuxppc.org ]]