From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 16 Mar 2004 12:40:30 +0100 From: Marc Leeman To: linuxppc-dev@lists.linuxppc.org Subject: PCI Memory mapping Message-ID: <20040316114030.GB7133@smtp.barco.com> Reply-To: Marc Leeman Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: I am currently trying the following +-----+ +-----+ | mem | | mem | +-----+ +-----+ | | +-----+ +-----+ | ppc | | dsp | +-----+ +-----+ | pci | +--------------+ For a number of reasons (load on ppc, dsp silicon bug), we are trying to transform the ppc dma transfers (ppc master write) to transfers initiated by the dsp; where the memory block that is the result of processing by the ppc is fetched by the dsp (ppc slave read). Mapping pci devices registers and memory into ppc kernel memory is well documented, but I seem to be missing information about the other way around: I (ppc) want to signal the dsp that data is ready at address 0xXXXXXXXX, come and get it (virt_to_bus(0xXXXXXXXX)?). Most likely I have been searching archives with the wrong keywords since I haven't found a good reference next to some notes in IO-mapping.txt which seem to indicate that this is possible. Any pointers about making cpu memory visible on the pci bus would greatly be appreciated. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/