remoteproc: create vdev subdevice with specific dma memory pool

This patch creates a dedicated vdev subdevice for each vdev declared
in firmware resource table and associates carveout named "vdev%dbuffer"
(with %d vdev index in resource table) if any as dma coherent memory pool.

Then vdev subdevice is used as parent for virtio device.

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

1 files changed, 41 insertions, 1 deletions

diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index 183fc42a510a..d08b2cfd875b 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -17,7 +17,9 @@
  * GNU General Public License for more details.
  */
 
+#include <linux/dma-mapping.h>
 #include <linux/export.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/remoteproc.h>
 #include <linux/virtio.h>
 #include <linux/virtio_config.h>
@@ -328,10 +330,48 @@ static void rproc_virtio_dev_release(struct device *dev)
 int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
 {
 	struct rproc *rproc = rvdev->rproc;
-	struct device *dev = &rproc->dev;
+	struct device *dev = &rvdev->dev;
 	struct virtio_device *vdev = &rvdev->vdev;
+	struct rproc_mem_entry *mem;
 	int ret;
 
+	/* Try to find dedicated vdev buffer carveout */
+	mem = rproc_find_carveout_by_name(rproc, "vdev%dbuffer", rvdev->index);
+	if (mem) {
+		phys_addr_t pa;
+
+		if (mem->of_resm_idx != -1) {
+			struct device_node *np = rproc->dev.parent->of_node;
+
+			/* Associate reserved memory to vdev device */
+			ret = of_reserved_mem_device_init_by_idx(dev, np,
+								 mem->of_resm_idx);
+			if (ret) {
+				dev_err(dev, "Can't associate reserved memory\n");
+				goto out;
+			}
+		} else {
+			if (mem->va) {
+				dev_warn(dev, "vdev %d buffer already mapped\n",
+					 rvdev->index);
+				pa = rproc_va_to_pa(mem->va);
+			} else {
+				/* Use dma address as carveout no memmapped yet */
+				pa = (phys_addr_t)mem->dma;
+			}
+
+			/* Associate vdev buffer memory pool to vdev subdev */
+			ret = dma_declare_coherent_memory(dev, pa,
+							   mem->da,
+							   mem->len,
+							   DMA_MEMORY_EXCLUSIVE);
+			if (ret < 0) {
+				dev_err(dev, "Failed to associate buffer\n");
+				goto out;
+			}
+		}
+	}
+
 	vdev->id.device	= id,
 	vdev->config = &rproc_virtio_config_ops,
 	vdev->dev.parent = dev;