On Mon, Apr 23, 2018 at 08:55:57AM +0000, Loic PALLARDY wrote: > > > > -----Original Message----- > > From: linux-remoteproc-owner@xxxxxxxxxxxxxxx [mailto:linux-remoteproc- > > owner@xxxxxxxxxxxxxxx] On Behalf Of Anup Patel > > Sent: Sunday, April 22, 2018 6:08 AM > > To: Michael S. Tsirkin <mst@xxxxxxxxxx> > > Cc: linux-remoteproc@xxxxxxxxxxxxxxx; Ohad Ben-Cohen > > <ohad@xxxxxxxxxx>; Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>; > > virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx > > Subject: Re: virtio remoteproc device > > > > On Fri, Apr 20, 2018 at 10:23 PM, Michael S. Tsirkin <mst@xxxxxxxxxx> > > wrote: > > > Hello! > > > I note the following in the serial console: > > > > > > if (is_rproc_serial(vdev)) { > > > /* > > > * Allocate DMA memory from ancestor. When a virtio > > > * device is created by remoteproc, the DMA memory is > > > * associated with the grandparent device: > > > * vdev => rproc => platform-dev. > > > */ > > > if (!vdev->dev.parent || !vdev->dev.parent->parent) > > > goto free_buf; > > > buf->dev = vdev->dev.parent->parent; > > > > > > /* Increase device refcnt to avoid freeing it */ > > > get_device(buf->dev); > > > buf->buf = dma_alloc_coherent(buf->dev, buf_size, &buf->dma, > > > GFP_KERNEL); > > > } > > > > > > Added here: > > > commit 1b6370463e88b0c1c317de16d7b962acc1dab4f2 > > > Author: Sjur Brændeland <sjur.brandeland@xxxxxxxxxxxxxx> > > > Date: Fri Dec 14 14:40:51 2012 +1030 > > > > > > virtio_console: Add support for remoteproc serial > > > > > > > > > I am not familiar with rproc so I have a question: > > > why is it required to use coherent memory here, > > > and why through a grandparent device? > > > > I faced similar issue when I tried VirtIO RPMSG bus over > > VirtIO MMIO transport. > > > > Here's my fix for VirtIO RPMSG bus driver: > > https://patchwork.kernel.org/patch/10155145/ > > Hi Anup and Michael, > > I pushed a series to modify virtio device allocation in remoteproc. Please see [1]. > It allows to remove allocation based on "grand-parent" device in the case of virtio device allocated by remoteproc. > Virto_console patch missing, only virtio_rpmsg modification proposed. I can add it in next version. > > Regards, > Loic > > [1] https://lkml.org/lkml/2018/3/1/644 > > > > > Regards, > > Anup > > -- > > 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 So on top of your patches, can we just force use of DMA API and drop special casting? E.g. maybe something like the below - completely untested - patch? Does it work for you? diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 2108551..6c6767c 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -40,7 +40,8 @@ #include <linux/dma-mapping.h> #include "../tty/hvc/hvc_console.h" -#define is_rproc_enabled IS_ENABLED(CONFIG_REMOTEPROC) +//#define is_rproc_enabled IS_ENABLED(CONFIG_REMOTEPROC) +#define is_rproc_enabled 0 /* * This is a global struct for storing common data for all the devices diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c index b0633fd..4a13ca2 100644 --- a/drivers/remoteproc/remoteproc_virtio.c +++ b/drivers/remoteproc/remoteproc_virtio.c @@ -199,7 +199,7 @@ static u64 rproc_virtio_get_features(struct virtio_device *vdev) rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset; - return rsc->dfeatures; + return rsc->dfeatures | (1ULL << VIRTIO_F_IOMMU_PLATFORM); } static int rproc_virtio_finalize_features(struct virtio_device *vdev) @@ -213,7 +213,7 @@ static int rproc_virtio_finalize_features(struct virtio_device *vdev) vring_transport_features(vdev); /* Make sure we don't have any features > 32 bits! */ - BUG_ON((u32)vdev->features != vdev->features); + //BUG_ON((u32)vdev->features != vdev->features); /* * Remember the finalized features of our vdev, and provide it _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization