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, 44 insertions, 3 deletions

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 54ec38fc5dca..821dbedef18e 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -39,9 +39,11 @@
 #include <linux/idr.h>
 #include <linux/elf.h>
 #include <linux/crc32.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/virtio_ids.h>
 #include <linux/virtio_ring.h>
 #include <asm/byteorder.h>
+#include <linux/platform_device.h>
 
 #include "remoteproc_internal.h"
 
@@ -145,7 +147,7 @@ static void rproc_disable_iommu(struct rproc *rproc)
 	iommu_domain_free(domain);
 }
 
-static phys_addr_t rproc_va_to_pa(void *cpu_addr)
+phys_addr_t rproc_va_to_pa(void *cpu_addr)
 {
 	/*
 	 * Return physical address according to virtual address location
@@ -160,6 +162,7 @@ static phys_addr_t rproc_va_to_pa(void *cpu_addr)
 	WARN_ON(!virt_addr_valid(cpu_addr));
 	return virt_to_phys(cpu_addr);
 }
+EXPORT_SYMBOL(rproc_va_to_pa);
 
 /**
  * rproc_da_to_va() - lookup the kernel virtual address for a remoteproc address
@@ -423,6 +426,20 @@ static void rproc_vdev_do_stop(struct rproc_subdev *subdev, bool crashed)
 }
 
 /**
+ * rproc_rvdev_release() - release the existence of a rvdev
+ *
+ * @dev: the subdevice's dev
+ */
+static void rproc_rvdev_release(struct device *dev)
+{
+	struct rproc_vdev *rvdev = container_of(dev, struct rproc_vdev, dev);
+
+	of_reserved_mem_device_release(dev);
+
+	kfree(rvdev);
+}
+
+/**
  * rproc_handle_vdev() - handle a vdev fw resource
  * @rproc: the remote processor
  * @rsc: the vring resource descriptor
@@ -455,6 +472,7 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
 	struct device *dev = &rproc->dev;
 	struct rproc_vdev *rvdev;
 	int i, ret;
+	char name[16];
 
 	/* make sure resource isn't truncated */
 	if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct fw_rsc_vdev_vring)
@@ -488,6 +506,29 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
 	rvdev->rproc = rproc;
 	rvdev->index = rproc->nb_vdev++;
 
+	/* Initialise vdev subdevice */
+	snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
+	rvdev->dev.parent = rproc->dev.parent;
+	rvdev->dev.release = rproc_rvdev_release;
+	dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev->dev.parent), name);
+	dev_set_drvdata(&rvdev->dev, rvdev);
+
+	ret = device_register(&rvdev->dev);
+	if (ret) {
+		put_device(&rvdev->dev);
+		return ret;
+	}
+	/* Make device dma capable by inheriting from parent's capabilities */
+	set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
+
+	ret = dma_coerce_mask_and_coherent(&rvdev->dev,
+					   dma_get_mask(rproc->dev.parent));
+	if (ret) {
+		dev_warn(dev,
+			 "Failed to set DMA mask %llx. Trying to continue... %x\n",
+			 dma_get_mask(rproc->dev.parent), ret);
+	}
+
 	/* parse the vrings */
 	for (i = 0; i < rsc->num_of_vrings; i++) {
 		ret = rproc_parse_vring(rvdev, rsc, i);
@@ -518,7 +559,7 @@ unwind_vring_allocations:
 	for (i--; i >= 0; i--)
 		rproc_free_vring(&rvdev->vring[i]);
 free_rvdev:
-	kfree(rvdev);
+	device_unregister(&rvdev->dev);
 	return ret;
 }
 
@@ -536,7 +577,7 @@ void rproc_vdev_release(struct kref *ref)
 
 	rproc_remove_subdev(rproc, &rvdev->subdev);
 	list_del(&rvdev->node);
-	kfree(rvdev);
+	device_unregister(&rvdev->dev);
 }
 
 /**