From: "ext Blanchard, Hollis" <hollis_blanch...@mentor.com> Subject: Re: [RFC] Inter-processor Mailboxes Drivers Date: Tue, 15 Feb 2011 15:38:25 -0800
> On 02/15/2011 01:58 PM, Meador Inge wrote: >> On 02/14/2011 04:01 AM, Jamie Iles wrote: >>> On Fri, Feb 11, 2011 at 03:19:51PM -0600, Meador Inge wrote: >>>> 1. Hardware specific bits somewhere under '.../arch/*'. Drivers >>>> for the MPIC message registers on Power and OMAP4 mailboxes, >>>> for >>>> example. >>>> 2. A higher level driver under '.../drivers/mailbox/*'. That the >>>> pieces in (1) would register with. This piece would expose the >>>> main kernel API. >>>> 3. Userspace interfaces for accessing the mailboxes. A >>>> '/dev/mailbox1', '/dev/mailbox2', etc... mapping, for example. >>> >>> How about using virtio for all of this and having the mailbox as a >>> notification/message passing driver for the virtio backend? There are >>> already virtio console and network drivers that could be useful for the >>> userspace part of it. drivers/virtio/virtio_ring.c might be a good >>> starting point if you thought there was some mileage in this approach. >> >> To be honest, I am not that familiar with 'virtio', but I will take a >> look. Thanks for the pointer. Maybe Hollis can speak to this idea more. > My opinion is that virtio is (over?) complicated. Considering the case of omap mailbox H/W, it is just a simple one way 4 slot x 32bit H/W FIFO, I also may think that this may be a bit too much... > I've looked into it in the past, and I'm definitely open to using it if > somebody can demonstrate how easy it is, but adopting it wouldn't have > helped OpenMCAPI with our use cases, and would have incurred extra pain, > so we didn't. > > Hollis Blanchard > Mentor Graphics, Embedded Systems Division > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
