[PATCH 0/3] remoteproc: complete fixed memory region support

[PATCH 0/3] remoteproc: complete fixed memory region support

[Loic Pallardy]

This new series corresponds to the remaining patches from [1]
addressing fixed memory region support for remote processor.

The three remaining patches allow to:
- assign a specific memory region to vdev sub device. As all virtio based
  services are using virtio device parent for memory allocation, I propose to
  keep a dedicated vdev device per virtio link for memory allocation. A second
  step will be to used virtio device itself.
- migrate ST driver on new memory carveout management
- allocate virtio rpmsg buffer from parent device

Regards,
Loic


[1] https://lkml.org/lkml/2018/7/27/612

Loic Pallardy (3):
  remoteproc: create vdev subdevice with specific dma memory pool
  remoteproc: st: add reserved memory support
  rpmsg: virtio: allocate buffer from parent

 drivers/remoteproc/remoteproc_core.c     | 46 ++++++++++++++--
 drivers/remoteproc/remoteproc_internal.h |  1 +
 drivers/remoteproc/remoteproc_virtio.c   | 42 ++++++++++++++-
 drivers/remoteproc/st_remoteproc.c       | 91 ++++++++++++++++++++++++++++----
 drivers/rpmsg/virtio_rpmsg_bus.c         |  6 +--
 include/linux/remoteproc.h               |  1 +
 6 files changed, 169 insertions(+), 18 deletions(-)

-- 
2.7.4

[PATCH 1/3] remoteproc: create vdev subdevice with specific dma memory pool

[Loic Pallardy]

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>
---
 drivers/remoteproc/remoteproc_core.c     | 46 +++++++++++++++++++++++++++++---
 drivers/remoteproc/remoteproc_internal.h |  1 +
 drivers/remoteproc/remoteproc_virtio.c   | 42 ++++++++++++++++++++++++++++-
 include/linux/remoteproc.h               |  1 +
 4 files changed, 86 insertions(+), 4 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 54ec38fc5dca..49272da6edd7 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 +506,28 @@ 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)
+		goto free_rvdev;
+
+	/* 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 +558,7 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
 	for (i--; i >= 0; i--)
 		rproc_free_vring(&rvdev->vring[i]);
 free_rvdev:
-	kfree(rvdev);
+	device_unregister(&rvdev->dev);
 	return ret;
 }
 
@@ -536,7 +576,7 @@ void rproc_vdev_release(struct kref *ref)
 
 	rproc_remove_subdev(rproc, &rvdev->subdev);
 	list_del(&rvdev->node);
-	kfree(rvdev);
+	device_unregister(&rvdev->dev);
 }
 
 /**
diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
index f6cad243d7ca..bfeacfd40947 100644
--- a/drivers/remoteproc/remoteproc_internal.h
+++ b/drivers/remoteproc/remoteproc_internal.h
@@ -52,6 +52,7 @@ void rproc_free_vring(struct rproc_vring *rvring);
 int rproc_alloc_vring(struct rproc_vdev *rvdev, int i);
 
 void *rproc_da_to_va(struct rproc *rproc, u64 da, int len);
+phys_addr_t rproc_va_to_pa(void *cpu_addr);
 int rproc_trigger_recovery(struct rproc *rproc);
 
 int rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw);
diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index de21f620b882..9ee63c0dfbc3 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>
@@ -315,10 +317,48 @@ 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 = dmam_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;
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 507a2b524208..beecd8cf2eb5 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -554,6 +554,7 @@ struct rproc_vdev {
 	struct kref refcount;
 
 	struct rproc_subdev subdev;
+	struct device dev;
 
 	unsigned int id;
 	struct list_head node;
-- 
2.7.4

[PATCH 2/3] remoteproc: st: add reserved memory support

[Loic Pallardy]

ST remote processor needs some specified memory regions for
firmware and IPC.
Memory regions are defined as reserved memory and should
be registered in remoteproc core thanks to rproc_add_carveout
function before rproc_start. For this, st rproc driver implements
prepare ops.

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
---
 drivers/remoteproc/st_remoteproc.c | 91 +++++++++++++++++++++++++++++++++-----
 1 file changed, 80 insertions(+), 11 deletions(-)

diff --git a/drivers/remoteproc/st_remoteproc.c b/drivers/remoteproc/st_remoteproc.c
index aacef0ea3b90..51049d17b1e5 100644
--- a/drivers/remoteproc/st_remoteproc.c
+++ b/drivers/remoteproc/st_remoteproc.c
@@ -19,6 +19,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
@@ -91,6 +92,77 @@ static void st_rproc_kick(struct rproc *rproc, int vqid)
 		dev_err(dev, "failed to send message via mbox: %d\n", ret);
 }
 
+static int st_rproc_mem_alloc(struct rproc *rproc,
+			      struct rproc_mem_entry *mem)
+{
+	struct device *dev = rproc->dev.parent;
+	void *va;
+
+	va = ioremap_wc(mem->dma, mem->len);
+	if (!va) {
+		dev_err(dev, "Unable to map memory region: %pa+%zx\n",
+			&mem->dma, mem->len);
+		return -ENOMEM;
+	}
+
+	/* Update memory entry va */
+	mem->va = va;
+
+	return 0;
+}
+
+static int st_rproc_mem_release(struct rproc *rproc,
+				struct rproc_mem_entry *mem)
+{
+	iounmap(mem->va);
+
+	return 0;
+}
+
+static int st_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
+{
+	struct device *dev = rproc->dev.parent;
+	struct device_node *np = dev->of_node;
+	struct rproc_mem_entry *mem;
+	struct reserved_mem *rmem;
+	struct of_phandle_iterator it;
+	int index = 0;
+
+	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
+	while (of_phandle_iterator_next(&it) == 0) {
+		rmem = of_reserved_mem_lookup(it.node);
+		if (!rmem) {
+			dev_err(dev, "unable to acquire memory-region\n");
+			return -EINVAL;
+		}
+
+		/*  No need to map vdev buffer */
+		if (strcmp(it.node->name, "vdev0buffer")) {
+			/* Register memory region */
+			mem = rproc_mem_entry_init(dev, NULL,
+						   (dma_addr_t)rmem->base,
+						   rmem->size, rmem->base,
+						   st_rproc_mem_alloc,
+						   st_rproc_mem_release,
+						   it.node->name);
+		} else {
+			/* Register reserved memory for vdev buffer allocation */
+			mem = rproc_of_resm_mem_entry_init(dev, index,
+							   rmem->size,
+							   rmem->base,
+							   it.node->name);
+		}
+
+		if (!mem)
+			return -ENOMEM;
+
+		rproc_add_carveout(rproc, mem);
+		index++;
+	}
+
+	return rproc_elf_load_rsc_table(rproc, fw);
+}
+
 static int st_rproc_start(struct rproc *rproc)
 {
 	struct st_rproc *ddata = rproc->priv;
@@ -158,9 +230,14 @@ static int st_rproc_stop(struct rproc *rproc)
 }
 
 static const struct rproc_ops st_rproc_ops = {
-	.kick		= st_rproc_kick,
-	.start		= st_rproc_start,
-	.stop		= st_rproc_stop,
+	.kick			= st_rproc_kick,
+	.start			= st_rproc_start,
+	.stop			= st_rproc_stop,
+	.parse_fw		= st_rproc_parse_fw,
+	.load			= rproc_elf_load_segments,
+	.find_loaded_rsc_table	= rproc_elf_find_loaded_rsc_table,
+	.sanity_check		= rproc_elf_sanity_check,
+	.get_boot_addr		= rproc_elf_get_boot_addr,
 };
 
 /*
@@ -254,12 +331,6 @@ static int st_rproc_parse_dt(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	err = of_reserved_mem_device_init(dev);
-	if (err) {
-		dev_err(dev, "Failed to obtain shared memory\n");
-		return err;
-	}
-
 	err = clk_prepare(ddata->clk);
 	if (err)
 		dev_err(dev, "failed to get clock\n");
@@ -387,8 +458,6 @@ static int st_rproc_remove(struct platform_device *pdev)
 
 	clk_disable_unprepare(ddata->clk);
 
-	of_reserved_mem_device_release(&pdev->dev);
-
 	for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
 		mbox_free_channel(ddata->mbox_chan[i]);
 
-- 
2.7.4

[PATCH 3/3] rpmsg: virtio: allocate buffer from parent

[Loic Pallardy]

Remoteproc is now capable to create one specific sub-device per
virtio link to associate a dedicated memory pool.
This implies to change device used by virtio_rpmsg for
buffer allocation from grand-parent to parent.

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Tested-by: Anup Patel <anup@brainfault.org>

---
 drivers/rpmsg/virtio_rpmsg_bus.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 664f957012cd..5c892019ce89 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -912,7 +912,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
 	total_buf_space = vrp->num_bufs * vrp->buf_size;
 
 	/* allocate coherent memory for the buffers */
-	bufs_va = dma_alloc_coherent(vdev->dev.parent->parent,
+	bufs_va = dma_alloc_coherent(vdev->dev.parent,
 				     total_buf_space, &vrp->bufs_dma,
 				     GFP_KERNEL);
 	if (!bufs_va) {
@@ -980,7 +980,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
 	return 0;
 
 free_coherent:
-	dma_free_coherent(vdev->dev.parent->parent, total_buf_space,
+	dma_free_coherent(vdev->dev.parent, total_buf_space,
 			  bufs_va, vrp->bufs_dma);
 vqs_del:
 	vdev->config->del_vqs(vrp->vdev);
@@ -1015,7 +1015,7 @@ static void rpmsg_remove(struct virtio_device *vdev)
 
 	vdev->config->del_vqs(vrp->vdev);
 
-	dma_free_coherent(vdev->dev.parent->parent, total_buf_space,
+	dma_free_coherent(vdev->dev.parent, total_buf_space,
 			  vrp->rbufs, vrp->bufs_dma);
 
 	kfree(vrp);
-- 
2.7.4