> -----Original Message----- > From: Suman Anna [mailto:s-anna@xxxxxx] > Sent: Saturday, January 14, 2017 3:41 AM > To: Loic PALLARDY <loic.pallardy@xxxxxx>; bjorn.andersson@xxxxxxxxxx; > ohad@xxxxxxxxxx; lee.jones@xxxxxxxxxx; Patrice CHOTARD > <patrice.chotard@xxxxxx> > Cc: linux-remoteproc@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxx > Subject: Re: [PATCH v1 6/6] rpmsg: virtio_rpmsg: set buffer configuration to > virtio > > On 12/07/2016 02:35 PM, Loic Pallardy wrote: > > Rpmsg is allocating buffer one dedicated communication link with some > > specificity like number of buffers, size of one buffer... > > These characteristics should be shared with remote coprocessor to > > guarantee communication link coherency. > > > > Proposal is to update rpmsg configuration fields in coprocessor > > firmware resource table if it exists. > > > > This is possible thanks to virtio set interface which allows to update > > cfg fields of struct fw_rsc_vdev. > > > > Signed-off-by: Loic Pallardy <loic.pallardy@xxxxxx> > > --- > > drivers/rpmsg/virtio_rpmsg_bus.c | 25 +++++++++++++++++++++++++ > > 1 file changed, 25 insertions(+) > > > > diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c > > b/drivers/rpmsg/virtio_rpmsg_bus.c > > index b12fe2a..5527b65 100644 > > --- a/drivers/rpmsg/virtio_rpmsg_bus.c > > +++ b/drivers/rpmsg/virtio_rpmsg_bus.c > > @@ -924,6 +924,23 @@ static int virtio_rpmsg_get_config(struct > > virtio_device *vdev) > > > > } > > > > +static void virtio_rpmsg_set_config(struct virtio_device *vdev) { > > + struct virtio_rpmsg_cfg virtio_cfg; > > + struct virtproc_info *vrp = vdev->priv; > > + > > + /* fill virtio_cfg struct */ > > + memset(&virtio_cfg, 0, sizeof(virtio_cfg)); > > + virtio_cfg.id = VIRTIO_ID_RPMSG; > > + virtio_cfg.da = vrp->bufs_dma; > > Hmm, I would expect this to fail if the device was behind an IOMMU. I think so. I think I did the same vring. I need to check. Perhaps better to set virtio_cfg.da to ANY_ADDRESS (-1) and add a comment about adding IOMMU support. What do you think? Regards, Loic > > regards > Suman > > > + virtio_cfg.pa = vrp->bufs_dma; > > + virtio_cfg.len = vrp->num_bufs * vrp->buf_size; > > + virtio_cfg.buf_size = vrp->buf_size; > > + > > + vdev->config->set(vdev, RPMSG_CONFIG_OFFSET, &virtio_cfg, > > + sizeof(virtio_cfg)); > > +} > > + > > static int rpmsg_probe(struct virtio_device *vdev) { > > vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done }; > @@ > > -934,6 +951,7 @@ static int rpmsg_probe(struct virtio_device *vdev) > > int err = 0, i; > > size_t total_buf_space; > > bool notify; > > + bool has_cfg = false; > > > > vrp = kzalloc(sizeof(*vrp), GFP_KERNEL); > > if (!vrp) > > @@ -973,6 +991,9 @@ static int rpmsg_probe(struct virtio_device *vdev) > > if (err < 0) > > goto free_vrp; > > > > + if (err) > > + has_cfg = true; > > + > > /* Allocate buffer if none provided by low level platform driver */ > > if (!vrp->ext_buffer) { > > total_buf_space = vrp->num_bufs * vrp->buf_size; @@ - > 993,6 +1014,10 > > @@ static int rpmsg_probe(struct virtio_device *vdev) > > > > /* and half is dedicated for TX */ > > vrp->sbufs = bufs_va + total_buf_space / 2; > > + > > + /* Notify configuration to coprocessor */ > > + if (has_cfg) > > + virtio_rpmsg_set_config(vdev); > > } > > > > /* set up the receive buffers */ > > -- To unsubscribe from this list: send the line "unsubscribe linux-remoteproc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
