Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2769 insertions, 0 deletions

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
new file mode 100644
index 0000000000..695cce218e
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -0,0 +1,2769 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Remote Processor Framework
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Ohad Ben-Cohen <ohad@wizery.com>
+ * Brian Swetland <swetland@google.com>
+ * Mark Grosen <mgrosen@ti.com>
+ * Fernando Guzman Lugo <fernando.lugo@ti.com>
+ * Suman Anna <s-anna@ti.com>
+ * Robert Tivy <rtivy@ti.com>
+ * Armando Uribe De Leon <x0095078@ti.com>
+ */
+
+#define pr_fmt(fmt)    "%s: " fmt, __func__
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/panic_notifier.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/dma-mapping.h>
+#include <linux/firmware.h>
+#include <linux/string.h>
+#include <linux/debugfs.h>
+#include <linux/rculist.h>
+#include <linux/remoteproc.h>
+#include <linux/iommu.h>
+#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"
+
+#define HIGH_BITS_MASK 0xFFFFFFFF00000000ULL
+
+static DEFINE_MUTEX(rproc_list_mutex);
+static LIST_HEAD(rproc_list);
+static struct notifier_block rproc_panic_nb;
+
+typedef int (*rproc_handle_resource_t)(struct rproc *rproc,
+				 void *, int offset, int avail);
+
+static int rproc_alloc_carveout(struct rproc *rproc,
+				struct rproc_mem_entry *mem);
+static int rproc_release_carveout(struct rproc *rproc,
+				  struct rproc_mem_entry *mem);
+
+/* Unique indices for remoteproc devices */
+static DEFINE_IDA(rproc_dev_index);
+static struct workqueue_struct *rproc_recovery_wq;
+
+static const char * const rproc_crash_names[] = {
+	[RPROC_MMUFAULT]	= "mmufault",
+	[RPROC_WATCHDOG]	= "watchdog",
+	[RPROC_FATAL_ERROR]	= "fatal error",
+};
+
+/* translate rproc_crash_type to string */
+static const char *rproc_crash_to_string(enum rproc_crash_type type)
+{
+	if (type < ARRAY_SIZE(rproc_crash_names))
+		return rproc_crash_names[type];
+	return "unknown";
+}
+
+/*
+ * This is the IOMMU fault handler we register with the IOMMU API
+ * (when relevant; not all remote processors access memory through
+ * an IOMMU).
+ *
+ * IOMMU core will invoke this handler whenever the remote processor
+ * will try to access an unmapped device address.
+ */
+static int rproc_iommu_fault(struct iommu_domain *domain, struct device *dev,
+			     unsigned long iova, int flags, void *token)
+{
+	struct rproc *rproc = token;
+
+	dev_err(dev, "iommu fault: da 0x%lx flags 0x%x\n", iova, flags);
+
+	rproc_report_crash(rproc, RPROC_MMUFAULT);
+
+	/*
+	 * Let the iommu core know we're not really handling this fault;
+	 * we just used it as a recovery trigger.
+	 */
+	return -ENOSYS;
+}
+
+static int rproc_enable_iommu(struct rproc *rproc)
+{
+	struct iommu_domain *domain;
+	struct device *dev = rproc->dev.parent;
+	int ret;
+
+	if (!rproc->has_iommu) {
+		dev_dbg(dev, "iommu not present\n");
+		return 0;
+	}
+
+	domain = iommu_domain_alloc(dev->bus);
+	if (!domain) {
+		dev_err(dev, "can't alloc iommu domain\n");
+		return -ENOMEM;
+	}
+
+	iommu_set_fault_handler(domain, rproc_iommu_fault, rproc);
+
+	ret = iommu_attach_device(domain, dev);
+	if (ret) {
+		dev_err(dev, "can't attach iommu device: %d\n", ret);
+		goto free_domain;
+	}
+
+	rproc->domain = domain;
+
+	return 0;
+
+free_domain:
+	iommu_domain_free(domain);
+	return ret;
+}
+
+static void rproc_disable_iommu(struct rproc *rproc)
+{
+	struct iommu_domain *domain = rproc->domain;
+	struct device *dev = rproc->dev.parent;
+
+	if (!domain)
+		return;
+
+	iommu_detach_device(domain, dev);
+	iommu_domain_free(domain);
+}
+
+phys_addr_t rproc_va_to_pa(void *cpu_addr)
+{
+	/*
+	 * Return physical address according to virtual address location
+	 * - in vmalloc: if region ioremapped or defined as dma_alloc_coherent
+	 * - in kernel: if region allocated in generic dma memory pool
+	 */
+	if (is_vmalloc_addr(cpu_addr)) {
+		return page_to_phys(vmalloc_to_page(cpu_addr)) +
+				    offset_in_page(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
+ * @rproc: handle of a remote processor
+ * @da: remoteproc device address to translate
+ * @len: length of the memory region @da is pointing to
+ * @is_iomem: optional pointer filled in to indicate if @da is iomapped memory
+ *
+ * Some remote processors will ask us to allocate them physically contiguous
+ * memory regions (which we call "carveouts"), and map them to specific
+ * device addresses (which are hardcoded in the firmware). They may also have
+ * dedicated memory regions internal to the processors, and use them either
+ * exclusively or alongside carveouts.
+ *
+ * They may then ask us to copy objects into specific device addresses (e.g.
+ * code/data sections) or expose us certain symbols in other device address
+ * (e.g. their trace buffer).
+ *
+ * This function is a helper function with which we can go over the allocated
+ * carveouts and translate specific device addresses to kernel virtual addresses
+ * so we can access the referenced memory. This function also allows to perform
+ * translations on the internal remoteproc memory regions through a platform
+ * implementation specific da_to_va ops, if present.
+ *
+ * Note: phys_to_virt(iommu_iova_to_phys(rproc->domain, da)) will work too,
+ * but only on kernel direct mapped RAM memory. Instead, we're just using
+ * here the output of the DMA API for the carveouts, which should be more
+ * correct.
+ *
+ * Return: a valid kernel address on success or NULL on failure
+ */
+void *rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem)
+{
+	struct rproc_mem_entry *carveout;
+	void *ptr = NULL;
+
+	if (rproc->ops->da_to_va) {
+		ptr = rproc->ops->da_to_va(rproc, da, len, is_iomem);
+		if (ptr)
+			goto out;
+	}
+
+	list_for_each_entry(carveout, &rproc->carveouts, node) {
+		int offset = da - carveout->da;
+
+		/*  Verify that carveout is allocated */
+		if (!carveout->va)
+			continue;
+
+		/* try next carveout if da is too small */
+		if (offset < 0)
+			continue;
+
+		/* try next carveout if da is too large */
+		if (offset + len > carveout->len)
+			continue;
+
+		ptr = carveout->va + offset;
+
+		if (is_iomem)
+			*is_iomem = carveout->is_iomem;
+
+		break;
+	}
+
+out:
+	return ptr;
+}
+EXPORT_SYMBOL(rproc_da_to_va);
+
+/**
+ * rproc_find_carveout_by_name() - lookup the carveout region by a name
+ * @rproc: handle of a remote processor
+ * @name: carveout name to find (format string)
+ * @...: optional parameters matching @name string
+ *
+ * Platform driver has the capability to register some pre-allacoted carveout
+ * (physically contiguous memory regions) before rproc firmware loading and
+ * associated resource table analysis. These regions may be dedicated memory
+ * regions internal to the coprocessor or specified DDR region with specific
+ * attributes
+ *
+ * This function is a helper function with which we can go over the
+ * allocated carveouts and return associated region characteristics like
+ * coprocessor address, length or processor virtual address.
+ *
+ * Return: a valid pointer on carveout entry on success or NULL on failure.
+ */
+__printf(2, 3)
+struct rproc_mem_entry *
+rproc_find_carveout_by_name(struct rproc *rproc, const char *name, ...)
+{
+	va_list args;
+	char _name[32];
+	struct rproc_mem_entry *carveout, *mem = NULL;
+
+	if (!name)
+		return NULL;
+
+	va_start(args, name);
+	vsnprintf(_name, sizeof(_name), name, args);
+	va_end(args);
+
+	list_for_each_entry(carveout, &rproc->carveouts, node) {
+		/* Compare carveout and requested names */
+		if (!strcmp(carveout->name, _name)) {
+			mem = carveout;
+			break;
+		}
+	}
+
+	return mem;
+}
+
+/**
+ * rproc_check_carveout_da() - Check specified carveout da configuration
+ * @rproc: handle of a remote processor
+ * @mem: pointer on carveout to check
+ * @da: area device address
+ * @len: associated area size
+ *
+ * This function is a helper function to verify requested device area (couple
+ * da, len) is part of specified carveout.
+ * If da is not set (defined as FW_RSC_ADDR_ANY), only requested length is
+ * checked.
+ *
+ * Return: 0 if carveout matches request else error
+ */
+static int rproc_check_carveout_da(struct rproc *rproc,
+				   struct rproc_mem_entry *mem, u32 da, u32 len)
+{
+	struct device *dev = &rproc->dev;
+	int delta;
+
+	/* Check requested resource length */
+	if (len > mem->len) {
+		dev_err(dev, "Registered carveout doesn't fit len request\n");
+		return -EINVAL;
+	}
+
+	if (da != FW_RSC_ADDR_ANY && mem->da == FW_RSC_ADDR_ANY) {
+		/* Address doesn't match registered carveout configuration */
+		return -EINVAL;
+	} else if (da != FW_RSC_ADDR_ANY && mem->da != FW_RSC_ADDR_ANY) {
+		delta = da - mem->da;
+
+		/* Check requested resource belongs to registered carveout */
+		if (delta < 0) {
+			dev_err(dev,
+				"Registered carveout doesn't fit da request\n");
+			return -EINVAL;
+		}
+
+		if (delta + len > mem->len) {
+			dev_err(dev,
+				"Registered carveout doesn't fit len request\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
+{
+	struct rproc *rproc = rvdev->rproc;
+	struct device *dev = &rproc->dev;
+	struct rproc_vring *rvring = &rvdev->vring[i];
+	struct fw_rsc_vdev *rsc;
+	int ret, notifyid;
+	struct rproc_mem_entry *mem;
+	size_t size;
+
+	/* actual size of vring (in bytes) */
+	size = PAGE_ALIGN(vring_size(rvring->num, rvring->align));
+
+	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
+
+	/* Search for pre-registered carveout */
+	mem = rproc_find_carveout_by_name(rproc, "vdev%dvring%d", rvdev->index,
+					  i);
+	if (mem) {
+		if (rproc_check_carveout_da(rproc, mem, rsc->vring[i].da, size))
+			return -ENOMEM;
+	} else {
+		/* Register carveout in list */
+		mem = rproc_mem_entry_init(dev, NULL, 0,
+					   size, rsc->vring[i].da,
+					   rproc_alloc_carveout,
+					   rproc_release_carveout,
+					   "vdev%dvring%d",
+					   rvdev->index, i);
+		if (!mem) {
+			dev_err(dev, "Can't allocate memory entry structure\n");
+			return -ENOMEM;
+		}
+
+		rproc_add_carveout(rproc, mem);
+	}
+
+	/*
+	 * Assign an rproc-wide unique index for this vring
+	 * TODO: assign a notifyid for rvdev updates as well
+	 * TODO: support predefined notifyids (via resource table)
+	 */
+	ret = idr_alloc(&rproc->notifyids, rvring, 0, 0, GFP_KERNEL);
+	if (ret < 0) {
+		dev_err(dev, "idr_alloc failed: %d\n", ret);
+		return ret;
+	}
+	notifyid = ret;
+
+	/* Potentially bump max_notifyid */
+	if (notifyid > rproc->max_notifyid)
+		rproc->max_notifyid = notifyid;
+
+	rvring->notifyid = notifyid;
+
+	/* Let the rproc know the notifyid of this vring.*/
+	rsc->vring[i].notifyid = notifyid;
+	return 0;
+}
+
+int
+rproc_parse_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i)
+{
+	struct rproc *rproc = rvdev->rproc;
+	struct device *dev = &rproc->dev;
+	struct fw_rsc_vdev_vring *vring = &rsc->vring[i];
+	struct rproc_vring *rvring = &rvdev->vring[i];
+
+	dev_dbg(dev, "vdev rsc: vring%d: da 0x%x, qsz %d, align %d\n",
+		i, vring->da, vring->num, vring->align);
+
+	/* verify queue size and vring alignment are sane */
+	if (!vring->num || !vring->align) {
+		dev_err(dev, "invalid qsz (%d) or alignment (%d)\n",
+			vring->num, vring->align);
+		return -EINVAL;
+	}
+
+	rvring->num = vring->num;
+	rvring->align = vring->align;
+	rvring->rvdev = rvdev;
+
+	return 0;
+}
+
+void rproc_free_vring(struct rproc_vring *rvring)
+{
+	struct rproc *rproc = rvring->rvdev->rproc;
+	int idx = rvring - rvring->rvdev->vring;
+	struct fw_rsc_vdev *rsc;
+
+	idr_remove(&rproc->notifyids, rvring->notifyid);
+
+	/*
+	 * At this point rproc_stop() has been called and the installed resource
+	 * table in the remote processor memory may no longer be accessible. As
+	 * such and as per rproc_stop(), rproc->table_ptr points to the cached
+	 * resource table (rproc->cached_table).  The cached resource table is
+	 * only available when a remote processor has been booted by the
+	 * remoteproc core, otherwise it is NULL.
+	 *
+	 * Based on the above, reset the virtio device section in the cached
+	 * resource table only if there is one to work with.
+	 */
+	if (rproc->table_ptr) {
+		rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset;
+		rsc->vring[idx].da = 0;
+		rsc->vring[idx].notifyid = -1;
+	}
+}
+
+void rproc_add_rvdev(struct rproc *rproc, struct rproc_vdev *rvdev)
+{
+	if (rvdev && rproc)
+		list_add_tail(&rvdev->node, &rproc->rvdevs);
+}
+
+void rproc_remove_rvdev(struct rproc_vdev *rvdev)
+{
+	if (rvdev)
+		list_del(&rvdev->node);
+}
+/**
+ * rproc_handle_vdev() - handle a vdev fw resource
+ * @rproc: the remote processor
+ * @ptr: the vring resource descriptor
+ * @offset: offset of the resource entry
+ * @avail: size of available data (for sanity checking the image)
+ *
+ * This resource entry requests the host to statically register a virtio
+ * device (vdev), and setup everything needed to support it. It contains
+ * everything needed to make it possible: the virtio device id, virtio
+ * device features, vrings information, virtio config space, etc...
+ *
+ * Before registering the vdev, the vrings are allocated from non-cacheable
+ * physically contiguous memory. Currently we only support two vrings per
+ * remote processor (temporary limitation). We might also want to consider
+ * doing the vring allocation only later when ->find_vqs() is invoked, and
+ * then release them upon ->del_vqs().
+ *
+ * Note: @da is currently not really handled correctly: we dynamically
+ * allocate it using the DMA API, ignoring requested hard coded addresses,
+ * and we don't take care of any required IOMMU programming. This is all
+ * going to be taken care of when the generic iommu-based DMA API will be
+ * merged. Meanwhile, statically-addressed iommu-based firmware images should
+ * use RSC_DEVMEM resource entries to map their required @da to the physical
+ * address of their base CMA region (ouch, hacky!).
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
+			     int offset, int avail)
+{
+	struct fw_rsc_vdev *rsc = ptr;
+	struct device *dev = &rproc->dev;
+	struct rproc_vdev *rvdev;
+	size_t rsc_size;
+	struct rproc_vdev_data rvdev_data;
+	struct platform_device *pdev;
+
+	/* make sure resource isn't truncated */
+	rsc_size = struct_size(rsc, vring, rsc->num_of_vrings);
+	if (size_add(rsc_size, rsc->config_len) > avail) {
+		dev_err(dev, "vdev rsc is truncated\n");
+		return -EINVAL;
+	}
+
+	/* make sure reserved bytes are zeroes */
+	if (rsc->reserved[0] || rsc->reserved[1]) {
+		dev_err(dev, "vdev rsc has non zero reserved bytes\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "vdev rsc: id %d, dfeatures 0x%x, cfg len %d, %d vrings\n",
+		rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings);
+
+	/* we currently support only two vrings per rvdev */
+	if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) {
+		dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings);
+		return -EINVAL;
+	}
+
+	rvdev_data.id = rsc->id;
+	rvdev_data.index = rproc->nb_vdev++;
+	rvdev_data.rsc_offset = offset;
+	rvdev_data.rsc = rsc;
+
+	/*
+	 * When there is more than one remote processor, rproc->nb_vdev number is
+	 * same for each separate instances of "rproc". If rvdev_data.index is used
+	 * as device id, then we get duplication in sysfs, so need to use
+	 * PLATFORM_DEVID_AUTO to auto select device id.
+	 */
+	pdev = platform_device_register_data(dev, "rproc-virtio", PLATFORM_DEVID_AUTO, &rvdev_data,
+					     sizeof(rvdev_data));
+	if (IS_ERR(pdev)) {
+		dev_err(dev, "failed to create rproc-virtio device\n");
+		return PTR_ERR(pdev);
+	}
+
+	return 0;
+}
+
+/**
+ * rproc_handle_trace() - handle a shared trace buffer resource
+ * @rproc: the remote processor
+ * @ptr: the trace resource descriptor
+ * @offset: offset of the resource entry
+ * @avail: size of available data (for sanity checking the image)
+ *
+ * In case the remote processor dumps trace logs into memory,
+ * export it via debugfs.
+ *
+ * Currently, the 'da' member of @rsc should contain the device address
+ * where the remote processor is dumping the traces. Later we could also
+ * support dynamically allocating this address using the generic
+ * DMA API (but currently there isn't a use case for that).
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_trace(struct rproc *rproc, void *ptr,
+			      int offset, int avail)
+{
+	struct fw_rsc_trace *rsc = ptr;
+	struct rproc_debug_trace *trace;
+	struct device *dev = &rproc->dev;
+	char name[15];
+
+	if (sizeof(*rsc) > avail) {
+		dev_err(dev, "trace rsc is truncated\n");
+		return -EINVAL;
+	}
+
+	/* make sure reserved bytes are zeroes */
+	if (rsc->reserved) {
+		dev_err(dev, "trace rsc has non zero reserved bytes\n");
+		return -EINVAL;
+	}
+
+	trace = kzalloc(sizeof(*trace), GFP_KERNEL);
+	if (!trace)
+		return -ENOMEM;
+
+	/* set the trace buffer dma properties */
+	trace->trace_mem.len = rsc->len;
+	trace->trace_mem.da = rsc->da;
+
+	/* set pointer on rproc device */
+	trace->rproc = rproc;
+
+	/* make sure snprintf always null terminates, even if truncating */
+	snprintf(name, sizeof(name), "trace%d", rproc->num_traces);
+
+	/* create the debugfs entry */
+	trace->tfile = rproc_create_trace_file(name, rproc, trace);
+
+	list_add_tail(&trace->node, &rproc->traces);
+
+	rproc->num_traces++;
+
+	dev_dbg(dev, "%s added: da 0x%x, len 0x%x\n",
+		name, rsc->da, rsc->len);
+
+	return 0;
+}
+
+/**
+ * rproc_handle_devmem() - handle devmem resource entry
+ * @rproc: remote processor handle
+ * @ptr: the devmem resource entry
+ * @offset: offset of the resource entry
+ * @avail: size of available data (for sanity checking the image)
+ *
+ * Remote processors commonly need to access certain on-chip peripherals.
+ *
+ * Some of these remote processors access memory via an iommu device,
+ * and might require us to configure their iommu before they can access
+ * the on-chip peripherals they need.
+ *
+ * This resource entry is a request to map such a peripheral device.
+ *
+ * These devmem entries will contain the physical address of the device in
+ * the 'pa' member. If a specific device address is expected, then 'da' will
+ * contain it (currently this is the only use case supported). 'len' will
+ * contain the size of the physical region we need to map.
+ *
+ * Currently we just "trust" those devmem entries to contain valid physical
+ * addresses, but this is going to change: we want the implementations to
+ * tell us ranges of physical addresses the firmware is allowed to request,
+ * and not allow firmwares to request access to physical addresses that
+ * are outside those ranges.
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_devmem(struct rproc *rproc, void *ptr,
+			       int offset, int avail)
+{
+	struct fw_rsc_devmem *rsc = ptr;
+	struct rproc_mem_entry *mapping;
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/* no point in handling this resource without a valid iommu domain */
+	if (!rproc->domain)
+		return -EINVAL;
+
+	if (sizeof(*rsc) > avail) {
+		dev_err(dev, "devmem rsc is truncated\n");
+		return -EINVAL;
+	}
+
+	/* make sure reserved bytes are zeroes */
+	if (rsc->reserved) {
+		dev_err(dev, "devmem rsc has non zero reserved bytes\n");
+		return -EINVAL;
+	}
+
+	mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
+	if (!mapping)
+		return -ENOMEM;
+
+	ret = iommu_map(rproc->domain, rsc->da, rsc->pa, rsc->len, rsc->flags,
+			GFP_KERNEL);
+	if (ret) {
+		dev_err(dev, "failed to map devmem: %d\n", ret);
+		goto out;
+	}
+
+	/*
+	 * We'll need this info later when we'll want to unmap everything
+	 * (e.g. on shutdown).
+	 *
+	 * We can't trust the remote processor not to change the resource
+	 * table, so we must maintain this info independently.
+	 */
+	mapping->da = rsc->da;
+	mapping->len = rsc->len;
+	list_add_tail(&mapping->node, &rproc->mappings);
+
+	dev_dbg(dev, "mapped devmem pa 0x%x, da 0x%x, len 0x%x\n",
+		rsc->pa, rsc->da, rsc->len);
+
+	return 0;
+
+out:
+	kfree(mapping);
+	return ret;
+}
+
+/**
+ * rproc_alloc_carveout() - allocated specified carveout
+ * @rproc: rproc handle
+ * @mem: the memory entry to allocate
+ *
+ * This function allocate specified memory entry @mem using
+ * dma_alloc_coherent() as default allocator
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_alloc_carveout(struct rproc *rproc,
+				struct rproc_mem_entry *mem)
+{
+	struct rproc_mem_entry *mapping = NULL;
+	struct device *dev = &rproc->dev;
+	dma_addr_t dma;
+	void *va;
+	int ret;
+
+	va = dma_alloc_coherent(dev->parent, mem->len, &dma, GFP_KERNEL);
+	if (!va) {
+		dev_err(dev->parent,
+			"failed to allocate dma memory: len 0x%zx\n",
+			mem->len);
+		return -ENOMEM;
+	}
+
+	dev_dbg(dev, "carveout va %pK, dma %pad, len 0x%zx\n",
+		va, &dma, mem->len);
+
+	if (mem->da != FW_RSC_ADDR_ANY && !rproc->domain) {
+		/*
+		 * Check requested da is equal to dma address
+		 * and print a warn message in case of missalignment.
+		 * Don't stop rproc_start sequence as coprocessor may
+		 * build pa to da translation on its side.
+		 */
+		if (mem->da != (u32)dma)
+			dev_warn(dev->parent,
+				 "Allocated carveout doesn't fit device address request\n");
+	}
+
+	/*
+	 * Ok, this is non-standard.
+	 *
+	 * Sometimes we can't rely on the generic iommu-based DMA API
+	 * to dynamically allocate the device address and then set the IOMMU
+	 * tables accordingly, because some remote processors might
+	 * _require_ us to use hard coded device addresses that their
+	 * firmware was compiled with.
+	 *
+	 * In this case, we must use the IOMMU API directly and map
+	 * the memory to the device address as expected by the remote
+	 * processor.
+	 *
+	 * Obviously such remote processor devices should not be configured
+	 * to use the iommu-based DMA API: we expect 'dma' to contain the
+	 * physical address in this case.
+	 */
+	if (mem->da != FW_RSC_ADDR_ANY && rproc->domain) {
+		mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
+		if (!mapping) {
+			ret = -ENOMEM;
+			goto dma_free;
+		}
+
+		ret = iommu_map(rproc->domain, mem->da, dma, mem->len,
+				mem->flags, GFP_KERNEL);
+		if (ret) {
+			dev_err(dev, "iommu_map failed: %d\n", ret);
+			goto free_mapping;
+		}
+
+		/*
+		 * We'll need this info later when we'll want to unmap
+		 * everything (e.g. on shutdown).
+		 *
+		 * We can't trust the remote processor not to change the
+		 * resource table, so we must maintain this info independently.
+		 */
+		mapping->da = mem->da;
+		mapping->len = mem->len;
+		list_add_tail(&mapping->node, &rproc->mappings);
+
+		dev_dbg(dev, "carveout mapped 0x%x to %pad\n",
+			mem->da, &dma);
+	}
+
+	if (mem->da == FW_RSC_ADDR_ANY) {
+		/* Update device address as undefined by requester */
+		if ((u64)dma & HIGH_BITS_MASK)
+			dev_warn(dev, "DMA address cast in 32bit to fit resource table format\n");
+
+		mem->da = (u32)dma;
+	}
+
+	mem->dma = dma;
+	mem->va = va;
+
+	return 0;
+
+free_mapping:
+	kfree(mapping);
+dma_free:
+	dma_free_coherent(dev->parent, mem->len, va, dma);
+	return ret;
+}
+
+/**
+ * rproc_release_carveout() - release acquired carveout
+ * @rproc: rproc handle
+ * @mem: the memory entry to release
+ *
+ * This function releases specified memory entry @mem allocated via
+ * rproc_alloc_carveout() function by @rproc.
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_release_carveout(struct rproc *rproc,
+				  struct rproc_mem_entry *mem)
+{
+	struct device *dev = &rproc->dev;
+
+	/* clean up carveout allocations */
+	dma_free_coherent(dev->parent, mem->len, mem->va, mem->dma);
+	return 0;
+}
+
+/**
+ * rproc_handle_carveout() - handle phys contig memory allocation requests
+ * @rproc: rproc handle
+ * @ptr: the resource entry
+ * @offset: offset of the resource entry
+ * @avail: size of available data (for image validation)
+ *
+ * This function will handle firmware requests for allocation of physically
+ * contiguous memory regions.
+ *
+ * These request entries should come first in the firmware's resource table,
+ * as other firmware entries might request placing other data objects inside
+ * these memory regions (e.g. data/code segments, trace resource entries, ...).
+ *
+ * Allocating memory this way helps utilizing the reserved physical memory
+ * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
+ * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
+ * pressure is important; it may have a substantial impact on performance.
+ *
+ * Return: 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_carveout(struct rproc *rproc,
+				 void *ptr, int offset, int avail)
+{
+	struct fw_rsc_carveout *rsc = ptr;
+	struct rproc_mem_entry *carveout;
+	struct device *dev = &rproc->dev;
+
+	if (sizeof(*rsc) > avail) {
+		dev_err(dev, "carveout rsc is truncated\n");
+		return -EINVAL;
+	}
+
+	/* make sure reserved bytes are zeroes */
+	if (rsc->reserved) {
+		dev_err(dev, "carveout rsc has non zero reserved bytes\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "carveout rsc: name: %s, da 0x%x, pa 0x%x, len 0x%x, flags 0x%x\n",
+		rsc->name, rsc->da, rsc->pa, rsc->len, rsc->flags);
+
+	/*
+	 * Check carveout rsc already part of a registered carveout,
+	 * Search by name, then check the da and length
+	 */
+	carveout = rproc_find_carveout_by_name(rproc, rsc->name);
+
+	if (carveout) {
+		if (carveout->rsc_offset != FW_RSC_ADDR_ANY) {
+			dev_err(dev,
+				"Carveout already associated to resource table\n");
+			return -ENOMEM;
+		}
+
+		if (rproc_check_carveout_da(rproc, carveout, rsc->da, rsc->len))
+			return -ENOMEM;
+
+		/* Update memory carveout with resource table info */
+		carveout->rsc_offset = offset;
+		carveout->flags = rsc->flags;
+
+		return 0;
+	}
+
+	/* Register carveout in list */
+	carveout = rproc_mem_entry_init(dev, NULL, 0, rsc->len, rsc->da,
+					rproc_alloc_carveout,
+					rproc_release_carveout, rsc->name);
+	if (!carveout) {
+		dev_err(dev, "Can't allocate memory entry structure\n");
+		return -ENOMEM;
+	}
+
+	carveout->flags = rsc->flags;
+	carveout->rsc_offset = offset;
+	rproc_add_carveout(rproc, carveout);
+
+	return 0;
+}
+
+/**
+ * rproc_add_carveout() - register an allocated carveout region
+ * @rproc: rproc handle
+ * @mem: memory entry to register
+ *
+ * This function registers specified memory entry in @rproc carveouts list.
+ * Specified carveout should have been allocated before registering.
+ */
+void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem)
+{
+	list_add_tail(&mem->node, &rproc->carveouts);
+}
+EXPORT_SYMBOL(rproc_add_carveout);
+
+/**
+ * rproc_mem_entry_init() - allocate and initialize rproc_mem_entry struct
+ * @dev: pointer on device struct
+ * @va: virtual address
+ * @dma: dma address
+ * @len: memory carveout length
+ * @da: device address
+ * @alloc: memory carveout allocation function
+ * @release: memory carveout release function
+ * @name: carveout name
+ *
+ * This function allocates a rproc_mem_entry struct and fill it with parameters
+ * provided by client.
+ *
+ * Return: a valid pointer on success, or NULL on failure
+ */
+__printf(8, 9)
+struct rproc_mem_entry *
+rproc_mem_entry_init(struct device *dev,
+		     void *va, dma_addr_t dma, size_t len, u32 da,
+		     int (*alloc)(struct rproc *, struct rproc_mem_entry *),
+		     int (*release)(struct rproc *, struct rproc_mem_entry *),
+		     const char *name, ...)
+{
+	struct rproc_mem_entry *mem;
+	va_list args;
+
+	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+	if (!mem)
+		return mem;
+
+	mem->va = va;
+	mem->dma = dma;
+	mem->da = da;
+	mem->len = len;
+	mem->alloc = alloc;
+	mem->release = release;
+	mem->rsc_offset = FW_RSC_ADDR_ANY;
+	mem->of_resm_idx = -1;
+
+	va_start(args, name);
+	vsnprintf(mem->name, sizeof(mem->name), name, args);
+	va_end(args);
+
+	return mem;
+}
+EXPORT_SYMBOL(rproc_mem_entry_init);
+
+/**
+ * rproc_of_resm_mem_entry_init() - allocate and initialize rproc_mem_entry struct
+ * from a reserved memory phandle
+ * @dev: pointer on device struct
+ * @of_resm_idx: reserved memory phandle index in "memory-region"
+ * @len: memory carveout length
+ * @da: device address
+ * @name: carveout name
+ *
+ * This function allocates a rproc_mem_entry struct and fill it with parameters
+ * provided by client.
+ *
+ * Return: a valid pointer on success, or NULL on failure
+ */
+__printf(5, 6)
+struct rproc_mem_entry *
+rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, size_t len,
+			     u32 da, const char *name, ...)
+{
+	struct rproc_mem_entry *mem;
+	va_list args;
+
+	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+	if (!mem)
+		return mem;
+
+	mem->da = da;
+	mem->len = len;
+	mem->rsc_offset = FW_RSC_ADDR_ANY;
+	mem->of_resm_idx = of_resm_idx;
+
+	va_start(args, name);
+	vsnprintf(mem->name, sizeof(mem->name), name, args);
+	va_end(args);
+
+	return mem;
+}
+EXPORT_SYMBOL(rproc_of_resm_mem_entry_init);
+
+/**
+ * rproc_of_parse_firmware() - parse and return the firmware-name
+ * @dev: pointer on device struct representing a rproc
+ * @index: index to use for the firmware-name retrieval
+ * @fw_name: pointer to a character string, in which the firmware
+ *           name is returned on success and unmodified otherwise.
+ *
+ * This is an OF helper function that parses a device's DT node for
+ * the "firmware-name" property and returns the firmware name pointer
+ * in @fw_name on success.
+ *
+ * Return: 0 on success, or an appropriate failure.
+ */
+int rproc_of_parse_firmware(struct device *dev, int index, const char **fw_name)
+{
+	int ret;
+
+	ret = of_property_read_string_index(dev->of_node, "firmware-name",
+					    index, fw_name);
+	return ret ? ret : 0;
+}
+EXPORT_SYMBOL(rproc_of_parse_firmware);
+
+/*
+ * A lookup table for resource handlers. The indices are defined in
+ * enum fw_resource_type.
+ */
+static rproc_handle_resource_t rproc_loading_handlers[RSC_LAST] = {
+	[RSC_CARVEOUT] = rproc_handle_carveout,
+	[RSC_DEVMEM] = rproc_handle_devmem,
+	[RSC_TRACE] = rproc_handle_trace,
+	[RSC_VDEV] = rproc_handle_vdev,
+};
+
+/* handle firmware resource entries before booting the remote processor */
+static int rproc_handle_resources(struct rproc *rproc,
+				  rproc_handle_resource_t handlers[RSC_LAST])
+{
+	struct device *dev = &rproc->dev;
+	rproc_handle_resource_t handler;
+	int ret = 0, i;
+
+	if (!rproc->table_ptr)
+		return 0;
+
+	for (i = 0; i < rproc->table_ptr->num; i++) {
+		int offset = rproc->table_ptr->offset[i];
+		struct fw_rsc_hdr *hdr = (void *)rproc->table_ptr + offset;
+		int avail = rproc->table_sz - offset - sizeof(*hdr);
+		void *rsc = (void *)hdr + sizeof(*hdr);
+
+		/* make sure table isn't truncated */
+		if (avail < 0) {
+			dev_err(dev, "rsc table is truncated\n");
+			return -EINVAL;
+		}
+
+		dev_dbg(dev, "rsc: type %d\n", hdr->type);
+
+		if (hdr->type >= RSC_VENDOR_START &&
+		    hdr->type <= RSC_VENDOR_END) {
+			ret = rproc_handle_rsc(rproc, hdr->type, rsc,
+					       offset + sizeof(*hdr), avail);
+			if (ret == RSC_HANDLED)
+				continue;
+			else if (ret < 0)
+				break;
+
+			dev_warn(dev, "unsupported vendor resource %d\n",
+				 hdr->type);
+			continue;
+		}
+
+		if (hdr->type >= RSC_LAST) {
+			dev_warn(dev, "unsupported resource %d\n", hdr->type);
+			continue;
+		}
+
+		handler = handlers[hdr->type];
+		if (!handler)
+			continue;
+
+		ret = handler(rproc, rsc, offset + sizeof(*hdr), avail);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+static int rproc_prepare_subdevices(struct rproc *rproc)
+{
+	struct rproc_subdev *subdev;
+	int ret;
+
+	list_for_each_entry(subdev, &rproc->subdevs, node) {
+		if (subdev->prepare) {
+			ret = subdev->prepare(subdev);
+			if (ret)
+				goto unroll_preparation;
+		}
+	}
+
+	return 0;
+
+unroll_preparation:
+	list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node) {
+		if (subdev->unprepare)
+			subdev->unprepare(subdev);
+	}
+
+	return ret;
+}
+
+static int rproc_start_subdevices(struct rproc *rproc)
+{
+	struct rproc_subdev *subdev;
+	int ret;
+
+	list_for_each_entry(subdev, &rproc->subdevs, node) {
+		if (subdev->start) {
+			ret = subdev->start(subdev);
+			if (ret)
+				goto unroll_registration;
+		}
+	}
+
+	return 0;
+
+unroll_registration:
+	list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node) {
+		if (subdev->stop)
+			subdev->stop(subdev, true);
+	}
+
+	return ret;
+}
+
+static void rproc_stop_subdevices(struct rproc *rproc, bool crashed)
+{
+	struct rproc_subdev *subdev;
+
+	list_for_each_entry_reverse(subdev, &rproc->subdevs, node) {
+		if (subdev->stop)
+			subdev->stop(subdev, crashed);
+	}
+}
+
+static void rproc_unprepare_subdevices(struct rproc *rproc)
+{
+	struct rproc_subdev *subdev;
+
+	list_for_each_entry_reverse(subdev, &rproc->subdevs, node) {
+		if (subdev->unprepare)
+			subdev->unprepare(subdev);
+	}
+}
+
+/**
+ * rproc_alloc_registered_carveouts() - allocate all carveouts registered
+ * in the list
+ * @rproc: the remote processor handle
+ *
+ * This function parses registered carveout list, performs allocation
+ * if alloc() ops registered and updates resource table information
+ * if rsc_offset set.
+ *
+ * Return: 0 on success
+ */
+static int rproc_alloc_registered_carveouts(struct rproc *rproc)
+{
+	struct rproc_mem_entry *entry, *tmp;
+	struct fw_rsc_carveout *rsc;
+	struct device *dev = &rproc->dev;
+	u64 pa;
+	int ret;
+
+	list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
+		if (entry->alloc) {
+			ret = entry->alloc(rproc, entry);
+			if (ret) {
+				dev_err(dev, "Unable to allocate carveout %s: %d\n",
+					entry->name, ret);
+				return -ENOMEM;
+			}
+		}
+
+		if (entry->rsc_offset != FW_RSC_ADDR_ANY) {
+			/* update resource table */
+			rsc = (void *)rproc->table_ptr + entry->rsc_offset;
+
+			/*
+			 * Some remote processors might need to know the pa
+			 * even though they are behind an IOMMU. E.g., OMAP4's
+			 * remote M3 processor needs this so it can control
+			 * on-chip hardware accelerators that are not behind
+			 * the IOMMU, and therefor must know the pa.
+			 *
+			 * Generally we don't want to expose physical addresses
+			 * if we don't have to (remote processors are generally
+			 * _not_ trusted), so we might want to do this only for
+			 * remote processor that _must_ have this (e.g. OMAP4's
+			 * dual M3 subsystem).
+			 *
+			 * Non-IOMMU processors might also want to have this info.
+			 * In this case, the device address and the physical address
+			 * are the same.
+			 */
+
+			/* Use va if defined else dma to generate pa */
+			if (entry->va)
+				pa = (u64)rproc_va_to_pa(entry->va);
+			else
+				pa = (u64)entry->dma;
+
+			if (((u64)pa) & HIGH_BITS_MASK)
+				dev_warn(dev,
+					 "Physical address cast in 32bit to fit resource table format\n");
+
+			rsc->pa = (u32)pa;
+			rsc->da = entry->da;
+			rsc->len = entry->len;
+		}
+	}
+
+	return 0;
+}
+
+
+/**
+ * rproc_resource_cleanup() - clean up and free all acquired resources
+ * @rproc: rproc handle
+ *
+ * This function will free all resources acquired for @rproc, and it
+ * is called whenever @rproc either shuts down or fails to boot.
+ */
+void rproc_resource_cleanup(struct rproc *rproc)
+{
+	struct rproc_mem_entry *entry, *tmp;
+	struct rproc_debug_trace *trace, *ttmp;
+	struct rproc_vdev *rvdev, *rvtmp;
+	struct device *dev = &rproc->dev;
+
+	/* clean up debugfs trace entries */
+	list_for_each_entry_safe(trace, ttmp, &rproc->traces, node) {
+		rproc_remove_trace_file(trace->tfile);
+		rproc->num_traces--;
+		list_del(&trace->node);
+		kfree(trace);
+	}
+
+	/* clean up iommu mapping entries */
+	list_for_each_entry_safe(entry, tmp, &rproc->mappings, node) {
+		size_t unmapped;
+
+		unmapped = iommu_unmap(rproc->domain, entry->da, entry->len);
+		if (unmapped != entry->len) {
+			/* nothing much to do besides complaining */
+			dev_err(dev, "failed to unmap %zx/%zu\n", entry->len,
+				unmapped);
+		}
+
+		list_del(&entry->node);
+		kfree(entry);
+	}
+
+	/* clean up carveout allocations */
+	list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
+		if (entry->release)
+			entry->release(rproc, entry);
+		list_del(&entry->node);
+		kfree(entry);
+	}
+
+	/* clean up remote vdev entries */
+	list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
+		platform_device_unregister(rvdev->pdev);
+
+	rproc_coredump_cleanup(rproc);
+}
+EXPORT_SYMBOL(rproc_resource_cleanup);
+
+static int rproc_start(struct rproc *rproc, const struct firmware *fw)
+{
+	struct resource_table *loaded_table;
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/* load the ELF segments to memory */
+	ret = rproc_load_segments(rproc, fw);
+	if (ret) {
+		dev_err(dev, "Failed to load program segments: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * The starting device has been given the rproc->cached_table as the
+	 * resource table. The address of the vring along with the other
+	 * allocated resources (carveouts etc) is stored in cached_table.
+	 * In order to pass this information to the remote device we must copy
+	 * this information to device memory. We also update the table_ptr so
+	 * that any subsequent changes will be applied to the loaded version.
+	 */
+	loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
+	if (loaded_table) {
+		memcpy(loaded_table, rproc->cached_table, rproc->table_sz);
+		rproc->table_ptr = loaded_table;
+	}
+
+	ret = rproc_prepare_subdevices(rproc);
+	if (ret) {
+		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
+			rproc->name, ret);
+		goto reset_table_ptr;
+	}
+
+	/* power up the remote processor */
+	ret = rproc->ops->start(rproc);
+	if (ret) {
+		dev_err(dev, "can't start rproc %s: %d\n", rproc->name, ret);
+		goto unprepare_subdevices;
+	}
+
+	/* Start any subdevices for the remote processor */
+	ret = rproc_start_subdevices(rproc);
+	if (ret) {
+		dev_err(dev, "failed to probe subdevices for %s: %d\n",
+			rproc->name, ret);
+		goto stop_rproc;
+	}
+
+	rproc->state = RPROC_RUNNING;
+
+	dev_info(dev, "remote processor %s is now up\n", rproc->name);
+
+	return 0;
+
+stop_rproc:
+	rproc->ops->stop(rproc);
+unprepare_subdevices:
+	rproc_unprepare_subdevices(rproc);
+reset_table_ptr:
+	rproc->table_ptr = rproc->cached_table;
+
+	return ret;
+}
+
+static int __rproc_attach(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = rproc_prepare_subdevices(rproc);
+	if (ret) {
+		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
+			rproc->name, ret);
+		goto out;
+	}
+
+	/* Attach to the remote processor */
+	ret = rproc_attach_device(rproc);
+	if (ret) {
+		dev_err(dev, "can't attach to rproc %s: %d\n",
+			rproc->name, ret);
+		goto unprepare_subdevices;
+	}
+
+	/* Start any subdevices for the remote processor */
+	ret = rproc_start_subdevices(rproc);
+	if (ret) {
+		dev_err(dev, "failed to probe subdevices for %s: %d\n",
+			rproc->name, ret);
+		goto stop_rproc;
+	}
+
+	rproc->state = RPROC_ATTACHED;
+
+	dev_info(dev, "remote processor %s is now attached\n", rproc->name);
+
+	return 0;
+
+stop_rproc:
+	rproc->ops->stop(rproc);
+unprepare_subdevices:
+	rproc_unprepare_subdevices(rproc);
+out:
+	return ret;
+}
+
+/*
+ * take a firmware and boot a remote processor with it.
+ */
+static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
+{
+	struct device *dev = &rproc->dev;
+	const char *name = rproc->firmware;
+	int ret;
+
+	ret = rproc_fw_sanity_check(rproc, fw);
+	if (ret)
+		return ret;
+
+	dev_info(dev, "Booting fw image %s, size %zd\n", name, fw->size);
+
+	/*
+	 * if enabling an IOMMU isn't relevant for this rproc, this is
+	 * just a nop
+	 */
+	ret = rproc_enable_iommu(rproc);
+	if (ret) {
+		dev_err(dev, "can't enable iommu: %d\n", ret);
+		return ret;
+	}
+
+	/* Prepare rproc for firmware loading if needed */
+	ret = rproc_prepare_device(rproc);
+	if (ret) {
+		dev_err(dev, "can't prepare rproc %s: %d\n", rproc->name, ret);
+		goto disable_iommu;
+	}
+
+	rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
+
+	/* Load resource table, core dump segment list etc from the firmware */
+	ret = rproc_parse_fw(rproc, fw);
+	if (ret)
+		goto unprepare_rproc;
+
+	/* reset max_notifyid */
+	rproc->max_notifyid = -1;
+
+	/* reset handled vdev */
+	rproc->nb_vdev = 0;
+
+	/* handle fw resources which are required to boot rproc */
+	ret = rproc_handle_resources(rproc, rproc_loading_handlers);
+	if (ret) {
+		dev_err(dev, "Failed to process resources: %d\n", ret);
+		goto clean_up_resources;
+	}
+
+	/* Allocate carveout resources associated to rproc */
+	ret = rproc_alloc_registered_carveouts(rproc);
+	if (ret) {
+		dev_err(dev, "Failed to allocate associated carveouts: %d\n",
+			ret);
+		goto clean_up_resources;
+	}
+
+	ret = rproc_start(rproc, fw);
+	if (ret)
+		goto clean_up_resources;
+
+	return 0;
+
+clean_up_resources:
+	rproc_resource_cleanup(rproc);
+	kfree(rproc->cached_table);
+	rproc->cached_table = NULL;
+	rproc->table_ptr = NULL;
+unprepare_rproc:
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
+disable_iommu:
+	rproc_disable_iommu(rproc);
+	return ret;
+}
+
+static int rproc_set_rsc_table(struct rproc *rproc)
+{
+	struct resource_table *table_ptr;
+	struct device *dev = &rproc->dev;
+	size_t table_sz;
+	int ret;
+
+	table_ptr = rproc_get_loaded_rsc_table(rproc, &table_sz);
+	if (!table_ptr) {
+		/* Not having a resource table is acceptable */
+		return 0;
+	}
+
+	if (IS_ERR(table_ptr)) {
+		ret = PTR_ERR(table_ptr);
+		dev_err(dev, "can't load resource table: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * If it is possible to detach the remote processor, keep an untouched
+	 * copy of the resource table.  That way we can start fresh again when
+	 * the remote processor is re-attached, that is:
+	 *
+	 *      DETACHED -> ATTACHED -> DETACHED -> ATTACHED
+	 *
+	 * Free'd in rproc_reset_rsc_table_on_detach() and
+	 * rproc_reset_rsc_table_on_stop().
+	 */
+	if (rproc->ops->detach) {
+		rproc->clean_table = kmemdup(table_ptr, table_sz, GFP_KERNEL);
+		if (!rproc->clean_table)
+			return -ENOMEM;
+	} else {
+		rproc->clean_table = NULL;
+	}
+
+	rproc->cached_table = NULL;
+	rproc->table_ptr = table_ptr;
+	rproc->table_sz = table_sz;
+
+	return 0;
+}
+
+static int rproc_reset_rsc_table_on_detach(struct rproc *rproc)
+{
+	struct resource_table *table_ptr;
+
+	/* A resource table was never retrieved, nothing to do here */
+	if (!rproc->table_ptr)
+		return 0;
+
+	/*
+	 * If we made it to this point a clean_table _must_ have been
+	 * allocated in rproc_set_rsc_table().  If one isn't present
+	 * something went really wrong and we must complain.
+	 */
+	if (WARN_ON(!rproc->clean_table))
+		return -EINVAL;
+
+	/* Remember where the external entity installed the resource table */
+	table_ptr = rproc->table_ptr;
+
+	/*
+	 * If we made it here the remote processor was started by another
+	 * entity and a cache table doesn't exist.  As such make a copy of
+	 * the resource table currently used by the remote processor and
+	 * use that for the rest of the shutdown process.  The memory
+	 * allocated here is free'd in rproc_detach().
+	 */
+	rproc->cached_table = kmemdup(rproc->table_ptr,
+				      rproc->table_sz, GFP_KERNEL);
+	if (!rproc->cached_table)
+		return -ENOMEM;
+
+	/*
+	 * Use a copy of the resource table for the remainder of the
+	 * shutdown process.
+	 */
+	rproc->table_ptr = rproc->cached_table;
+
+	/*
+	 * Reset the memory area where the firmware loaded the resource table
+	 * to its original value.  That way when we re-attach the remote
+	 * processor the resource table is clean and ready to be used again.
+	 */
+	memcpy(table_ptr, rproc->clean_table, rproc->table_sz);
+
+	/*
+	 * The clean resource table is no longer needed.  Allocated in
+	 * rproc_set_rsc_table().
+	 */
+	kfree(rproc->clean_table);
+
+	return 0;
+}
+
+static int rproc_reset_rsc_table_on_stop(struct rproc *rproc)
+{
+	/* A resource table was never retrieved, nothing to do here */
+	if (!rproc->table_ptr)
+		return 0;
+
+	/*
+	 * If a cache table exists the remote processor was started by
+	 * the remoteproc core.  That cache table should be used for
+	 * the rest of the shutdown process.
+	 */
+	if (rproc->cached_table)
+		goto out;
+
+	/*
+	 * If we made it here the remote processor was started by another
+	 * entity and a cache table doesn't exist.  As such make a copy of
+	 * the resource table currently used by the remote processor and
+	 * use that for the rest of the shutdown process.  The memory
+	 * allocated here is free'd in rproc_shutdown().
+	 */
+	rproc->cached_table = kmemdup(rproc->table_ptr,
+				      rproc->table_sz, GFP_KERNEL);
+	if (!rproc->cached_table)
+		return -ENOMEM;
+
+	/*
+	 * Since the remote processor is being switched off the clean table
+	 * won't be needed.  Allocated in rproc_set_rsc_table().
+	 */
+	kfree(rproc->clean_table);
+
+out:
+	/*
+	 * Use a copy of the resource table for the remainder of the
+	 * shutdown process.
+	 */
+	rproc->table_ptr = rproc->cached_table;
+	return 0;
+}
+
+/*
+ * Attach to remote processor - similar to rproc_fw_boot() but without
+ * the steps that deal with the firmware image.
+ */
+static int rproc_attach(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/*
+	 * if enabling an IOMMU isn't relevant for this rproc, this is
+	 * just a nop
+	 */
+	ret = rproc_enable_iommu(rproc);
+	if (ret) {
+		dev_err(dev, "can't enable iommu: %d\n", ret);
+		return ret;
+	}
+
+	/* Do anything that is needed to boot the remote processor */
+	ret = rproc_prepare_device(rproc);
+	if (ret) {
+		dev_err(dev, "can't prepare rproc %s: %d\n", rproc->name, ret);
+		goto disable_iommu;
+	}
+
+	ret = rproc_set_rsc_table(rproc);
+	if (ret) {
+		dev_err(dev, "can't load resource table: %d\n", ret);
+		goto unprepare_device;
+	}
+
+	/* reset max_notifyid */
+	rproc->max_notifyid = -1;
+
+	/* reset handled vdev */
+	rproc->nb_vdev = 0;
+
+	/*
+	 * Handle firmware resources required to attach to a remote processor.
+	 * Because we are attaching rather than booting the remote processor,
+	 * we expect the platform driver to properly set rproc->table_ptr.
+	 */
+	ret = rproc_handle_resources(rproc, rproc_loading_handlers);
+	if (ret) {
+		dev_err(dev, "Failed to process resources: %d\n", ret);
+		goto unprepare_device;
+	}
+
+	/* Allocate carveout resources associated to rproc */
+	ret = rproc_alloc_registered_carveouts(rproc);
+	if (ret) {
+		dev_err(dev, "Failed to allocate associated carveouts: %d\n",
+			ret);
+		goto clean_up_resources;
+	}
+
+	ret = __rproc_attach(rproc);
+	if (ret)
+		goto clean_up_resources;
+
+	return 0;
+
+clean_up_resources:
+	rproc_resource_cleanup(rproc);
+unprepare_device:
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
+disable_iommu:
+	rproc_disable_iommu(rproc);
+	return ret;
+}
+
+/*
+ * take a firmware and boot it up.
+ *
+ * Note: this function is called asynchronously upon registration of the
+ * remote processor (so we must wait until it completes before we try
+ * to unregister the device. one other option is just to use kref here,
+ * that might be cleaner).
+ */
+static void rproc_auto_boot_callback(const struct firmware *fw, void *context)
+{
+	struct rproc *rproc = context;
+
+	rproc_boot(rproc);
+
+	release_firmware(fw);
+}
+
+static int rproc_trigger_auto_boot(struct rproc *rproc)
+{
+	int ret;
+
+	/*
+	 * Since the remote processor is in a detached state, it has already
+	 * been booted by another entity.  As such there is no point in waiting
+	 * for a firmware image to be loaded, we can simply initiate the process
+	 * of attaching to it immediately.
+	 */
+	if (rproc->state == RPROC_DETACHED)
+		return rproc_boot(rproc);
+
+	/*
+	 * We're initiating an asynchronous firmware loading, so we can
+	 * be built-in kernel code, without hanging the boot process.
+	 */
+	ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT,
+				      rproc->firmware, &rproc->dev, GFP_KERNEL,
+				      rproc, rproc_auto_boot_callback);
+	if (ret < 0)
+		dev_err(&rproc->dev, "request_firmware_nowait err: %d\n", ret);
+
+	return ret;
+}
+
+static int rproc_stop(struct rproc *rproc, bool crashed)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/* No need to continue if a stop() operation has not been provided */
+	if (!rproc->ops->stop)
+		return -EINVAL;
+
+	/* Stop any subdevices for the remote processor */
+	rproc_stop_subdevices(rproc, crashed);
+
+	/* the installed resource table is no longer accessible */
+	ret = rproc_reset_rsc_table_on_stop(rproc);
+	if (ret) {
+		dev_err(dev, "can't reset resource table: %d\n", ret);
+		return ret;
+	}
+
+
+	/* power off the remote processor */
+	ret = rproc->ops->stop(rproc);
+	if (ret) {
+		dev_err(dev, "can't stop rproc: %d\n", ret);
+		return ret;
+	}
+
+	rproc_unprepare_subdevices(rproc);
+
+	rproc->state = RPROC_OFFLINE;
+
+	dev_info(dev, "stopped remote processor %s\n", rproc->name);
+
+	return 0;
+}
+
+/*
+ * __rproc_detach(): Does the opposite of __rproc_attach()
+ */
+static int __rproc_detach(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/* No need to continue if a detach() operation has not been provided */
+	if (!rproc->ops->detach)
+		return -EINVAL;
+
+	/* Stop any subdevices for the remote processor */
+	rproc_stop_subdevices(rproc, false);
+
+	/* the installed resource table is no longer accessible */
+	ret = rproc_reset_rsc_table_on_detach(rproc);
+	if (ret) {
+		dev_err(dev, "can't reset resource table: %d\n", ret);
+		return ret;
+	}
+
+	/* Tell the remote processor the core isn't available anymore */
+	ret = rproc->ops->detach(rproc);
+	if (ret) {
+		dev_err(dev, "can't detach from rproc: %d\n", ret);
+		return ret;
+	}
+
+	rproc_unprepare_subdevices(rproc);
+
+	rproc->state = RPROC_DETACHED;
+
+	dev_info(dev, "detached remote processor %s\n", rproc->name);
+
+	return 0;
+}
+
+static int rproc_attach_recovery(struct rproc *rproc)
+{
+	int ret;
+
+	ret = __rproc_detach(rproc);
+	if (ret)
+		return ret;
+
+	return __rproc_attach(rproc);
+}
+
+static int rproc_boot_recovery(struct rproc *rproc)
+{
+	const struct firmware *firmware_p;
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = rproc_stop(rproc, true);
+	if (ret)
+		return ret;
+
+	/* generate coredump */
+	rproc->ops->coredump(rproc);
+
+	/* load firmware */
+	ret = request_firmware(&firmware_p, rproc->firmware, dev);
+	if (ret < 0) {
+		dev_err(dev, "request_firmware failed: %d\n", ret);
+		return ret;
+	}
+
+	/* boot the remote processor up again */
+	ret = rproc_start(rproc, firmware_p);
+
+	release_firmware(firmware_p);
+
+	return ret;
+}
+
+/**
+ * rproc_trigger_recovery() - recover a remoteproc
+ * @rproc: the remote processor
+ *
+ * The recovery is done by resetting all the virtio devices, that way all the
+ * rpmsg drivers will be reseted along with the remote processor making the
+ * remoteproc functional again.
+ *
+ * This function can sleep, so it cannot be called from atomic context.
+ *
+ * Return: 0 on success or a negative value upon failure
+ */
+int rproc_trigger_recovery(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret)
+		return ret;
+
+	/* State could have changed before we got the mutex */
+	if (rproc->state != RPROC_CRASHED)
+		goto unlock_mutex;
+
+	dev_err(dev, "recovering %s\n", rproc->name);
+
+	if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_ON_RECOVERY))
+		ret = rproc_attach_recovery(rproc);
+	else
+		ret = rproc_boot_recovery(rproc);
+
+unlock_mutex:
+	mutex_unlock(&rproc->lock);
+	return ret;
+}
+
+/**
+ * rproc_crash_handler_work() - handle a crash
+ * @work: work treating the crash
+ *
+ * This function needs to handle everything related to a crash, like cpu
+ * registers and stack dump, information to help to debug the fatal error, etc.
+ */
+static void rproc_crash_handler_work(struct work_struct *work)
+{
+	struct rproc *rproc = container_of(work, struct rproc, crash_handler);
+	struct device *dev = &rproc->dev;
+
+	dev_dbg(dev, "enter %s\n", __func__);
+
+	mutex_lock(&rproc->lock);
+
+	if (rproc->state == RPROC_CRASHED) {
+		/* handle only the first crash detected */
+		mutex_unlock(&rproc->lock);
+		return;
+	}
+
+	if (rproc->state == RPROC_OFFLINE) {
+		/* Don't recover if the remote processor was stopped */
+		mutex_unlock(&rproc->lock);
+		goto out;
+	}
+
+	rproc->state = RPROC_CRASHED;
+	dev_err(dev, "handling crash #%u in %s\n", ++rproc->crash_cnt,
+		rproc->name);
+
+	mutex_unlock(&rproc->lock);
+
+	if (!rproc->recovery_disabled)
+		rproc_trigger_recovery(rproc);
+
+out:
+	pm_relax(rproc->dev.parent);
+}
+
+/**
+ * rproc_boot() - boot a remote processor
+ * @rproc: handle of a remote processor
+ *
+ * Boot a remote processor (i.e. load its firmware, power it on, ...).
+ *
+ * If the remote processor is already powered on, this function immediately
+ * returns (successfully).
+ *
+ * Return: 0 on success, and an appropriate error value otherwise
+ */
+int rproc_boot(struct rproc *rproc)
+{
+	const struct firmware *firmware_p;
+	struct device *dev;
+	int ret;
+
+	if (!rproc) {
+		pr_err("invalid rproc handle\n");
+		return -EINVAL;
+	}
+
+	dev = &rproc->dev;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret) {
+		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
+		return ret;
+	}
+
+	if (rproc->state == RPROC_DELETED) {
+		ret = -ENODEV;
+		dev_err(dev, "can't boot deleted rproc %s\n", rproc->name);
+		goto unlock_mutex;
+	}
+
+	/* skip the boot or attach process if rproc is already powered up */
+	if (atomic_inc_return(&rproc->power) > 1) {
+		ret = 0;
+		goto unlock_mutex;
+	}
+
+	if (rproc->state == RPROC_DETACHED) {
+		dev_info(dev, "attaching to %s\n", rproc->name);
+
+		ret = rproc_attach(rproc);
+	} else {
+		dev_info(dev, "powering up %s\n", rproc->name);
+
+		/* load firmware */
+		ret = request_firmware(&firmware_p, rproc->firmware, dev);
+		if (ret < 0) {
+			dev_err(dev, "request_firmware failed: %d\n", ret);
+			goto downref_rproc;
+		}
+
+		ret = rproc_fw_boot(rproc, firmware_p);
+
+		release_firmware(firmware_p);
+	}
+
+downref_rproc:
+	if (ret)
+		atomic_dec(&rproc->power);
+unlock_mutex:
+	mutex_unlock(&rproc->lock);
+	return ret;
+}
+EXPORT_SYMBOL(rproc_boot);
+
+/**
+ * rproc_shutdown() - power off the remote processor
+ * @rproc: the remote processor
+ *
+ * Power off a remote processor (previously booted with rproc_boot()).
+ *
+ * In case @rproc is still being used by an additional user(s), then
+ * this function will just decrement the power refcount and exit,
+ * without really powering off the device.
+ *
+ * Every call to rproc_boot() must (eventually) be accompanied by a call
+ * to rproc_shutdown(). Calling rproc_shutdown() redundantly is a bug.
+ *
+ * Notes:
+ * - we're not decrementing the rproc's refcount, only the power refcount.
+ *   which means that the @rproc handle stays valid even after rproc_shutdown()
+ *   returns, and users can still use it with a subsequent rproc_boot(), if
+ *   needed.
+ *
+ * Return: 0 on success, and an appropriate error value otherwise
+ */
+int rproc_shutdown(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret = 0;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret) {
+		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
+		return ret;
+	}
+
+	if (rproc->state != RPROC_RUNNING &&
+	    rproc->state != RPROC_ATTACHED) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* if the remote proc is still needed, bail out */
+	if (!atomic_dec_and_test(&rproc->power))
+		goto out;
+
+	ret = rproc_stop(rproc, false);
+	if (ret) {
+		atomic_inc(&rproc->power);
+		goto out;
+	}
+
+	/* clean up all acquired resources */
+	rproc_resource_cleanup(rproc);
+
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
+
+	rproc_disable_iommu(rproc);
+
+	/* Free the copy of the resource table */
+	kfree(rproc->cached_table);
+	rproc->cached_table = NULL;
+	rproc->table_ptr = NULL;
+out:
+	mutex_unlock(&rproc->lock);
+	return ret;
+}
+EXPORT_SYMBOL(rproc_shutdown);
+
+/**
+ * rproc_detach() - Detach the remote processor from the
+ * remoteproc core
+ *
+ * @rproc: the remote processor
+ *
+ * Detach a remote processor (previously attached to with rproc_attach()).
+ *
+ * In case @rproc is still being used by an additional user(s), then
+ * this function will just decrement the power refcount and exit,
+ * without disconnecting the device.
+ *
+ * Function rproc_detach() calls __rproc_detach() in order to let a remote
+ * processor know that services provided by the application processor are
+ * no longer available.  From there it should be possible to remove the
+ * platform driver and even power cycle the application processor (if the HW
+ * supports it) without needing to switch off the remote processor.
+ *
+ * Return: 0 on success, and an appropriate error value otherwise
+ */
+int rproc_detach(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret) {
+		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
+		return ret;
+	}
+
+	if (rproc->state != RPROC_ATTACHED) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* if the remote proc is still needed, bail out */
+	if (!atomic_dec_and_test(&rproc->power)) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = __rproc_detach(rproc);
+	if (ret) {
+		atomic_inc(&rproc->power);
+		goto out;
+	}
+
+	/* clean up all acquired resources */
+	rproc_resource_cleanup(rproc);
+
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
+
+	rproc_disable_iommu(rproc);
+
+	/* Free the copy of the resource table */
+	kfree(rproc->cached_table);
+	rproc->cached_table = NULL;
+	rproc->table_ptr = NULL;
+out:
+	mutex_unlock(&rproc->lock);
+	return ret;
+}
+EXPORT_SYMBOL(rproc_detach);
+
+/**
+ * rproc_get_by_phandle() - find a remote processor by phandle
+ * @phandle: phandle to the rproc
+ *
+ * Finds an rproc handle using the remote processor's phandle, and then
+ * return a handle to the rproc.
+ *
+ * This function increments the remote processor's refcount, so always
+ * use rproc_put() to decrement it back once rproc isn't needed anymore.
+ *
+ * Return: rproc handle on success, and NULL on failure
+ */
+#ifdef CONFIG_OF
+struct rproc *rproc_get_by_phandle(phandle phandle)
+{
+	struct rproc *rproc = NULL, *r;
+	struct device_node *np;
+
+	np = of_find_node_by_phandle(phandle);
+	if (!np)
+		return NULL;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(r, &rproc_list, node) {
+		if (r->dev.parent && device_match_of_node(r->dev.parent, np)) {
+			/* prevent underlying implementation from being removed */
+			if (!try_module_get(r->dev.parent->driver->owner)) {
+				dev_err(&r->dev, "can't get owner\n");
+				break;
+			}
+
+			rproc = r;
+			get_device(&rproc->dev);
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	of_node_put(np);
+
+	return rproc;
+}
+#else
+struct rproc *rproc_get_by_phandle(phandle phandle)
+{
+	return NULL;
+}
+#endif
+EXPORT_SYMBOL(rproc_get_by_phandle);
+
+/**
+ * rproc_set_firmware() - assign a new firmware
+ * @rproc: rproc handle to which the new firmware is being assigned
+ * @fw_name: new firmware name to be assigned
+ *
+ * This function allows remoteproc drivers or clients to configure a custom
+ * firmware name that is different from the default name used during remoteproc
+ * registration. The function does not trigger a remote processor boot,
+ * only sets the firmware name used for a subsequent boot. This function
+ * should also be called only when the remote processor is offline.
+ *
+ * This allows either the userspace to configure a different name through
+ * sysfs or a kernel-level remoteproc or a remoteproc client driver to set
+ * a specific firmware when it is controlling the boot and shutdown of the
+ * remote processor.
+ *
+ * Return: 0 on success or a negative value upon failure
+ */
+int rproc_set_firmware(struct rproc *rproc, const char *fw_name)
+{
+	struct device *dev;
+	int ret, len;
+	char *p;
+
+	if (!rproc || !fw_name)
+		return -EINVAL;
+
+	dev = rproc->dev.parent;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret) {
+		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
+		return -EINVAL;
+	}
+
+	if (rproc->state != RPROC_OFFLINE) {
+		dev_err(dev, "can't change firmware while running\n");
+		ret = -EBUSY;
+		goto out;
+	}
+
+	len = strcspn(fw_name, "\n");
+	if (!len) {
+		dev_err(dev, "can't provide empty string for firmware name\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	p = kstrndup(fw_name, len, GFP_KERNEL);
+	if (!p) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	kfree_const(rproc->firmware);
+	rproc->firmware = p;
+
+out:
+	mutex_unlock(&rproc->lock);
+	return ret;
+}
+EXPORT_SYMBOL(rproc_set_firmware);
+
+static int rproc_validate(struct rproc *rproc)
+{
+	switch (rproc->state) {
+	case RPROC_OFFLINE:
+		/*
+		 * An offline processor without a start()
+		 * function makes no sense.
+		 */
+		if (!rproc->ops->start)
+			return -EINVAL;
+		break;
+	case RPROC_DETACHED:
+		/*
+		 * A remote processor in a detached state without an
+		 * attach() function makes not sense.
+		 */
+		if (!rproc->ops->attach)
+			return -EINVAL;
+		/*
+		 * When attaching to a remote processor the device memory
+		 * is already available and as such there is no need to have a
+		 * cached table.
+		 */
+		if (rproc->cached_table)
+			return -EINVAL;
+		break;
+	default:
+		/*
+		 * When adding a remote processor, the state of the device
+		 * can be offline or detached, nothing else.
+		 */
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * rproc_add() - register a remote processor
+ * @rproc: the remote processor handle to register
+ *
+ * Registers @rproc with the remoteproc framework, after it has been
+ * allocated with rproc_alloc().
+ *
+ * This is called by the platform-specific rproc implementation, whenever
+ * a new remote processor device is probed.
+ *
+ * Note: this function initiates an asynchronous firmware loading
+ * context, which will look for virtio devices supported by the rproc's
+ * firmware.
+ *
+ * If found, those virtio devices will be created and added, so as a result
+ * of registering this remote processor, additional virtio drivers might be
+ * probed.
+ *
+ * Return: 0 on success and an appropriate error code otherwise
+ */
+int rproc_add(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = rproc_validate(rproc);
+	if (ret < 0)
+		return ret;
+
+	/* add char device for this remoteproc */
+	ret = rproc_char_device_add(rproc);
+	if (ret < 0)
+		return ret;
+
+	ret = device_add(dev);
+	if (ret < 0) {
+		put_device(dev);
+		goto rproc_remove_cdev;
+	}
+
+	dev_info(dev, "%s is available\n", rproc->name);
+
+	/* create debugfs entries */
+	rproc_create_debug_dir(rproc);
+
+	/* if rproc is marked always-on, request it to boot */
+	if (rproc->auto_boot) {
+		ret = rproc_trigger_auto_boot(rproc);
+		if (ret < 0)
+			goto rproc_remove_dev;
+	}
+
+	/* expose to rproc_get_by_phandle users */
+	mutex_lock(&rproc_list_mutex);
+	list_add_rcu(&rproc->node, &rproc_list);
+	mutex_unlock(&rproc_list_mutex);
+
+	return 0;
+
+rproc_remove_dev:
+	rproc_delete_debug_dir(rproc);
+	device_del(dev);
+rproc_remove_cdev:
+	rproc_char_device_remove(rproc);
+	return ret;
+}
+EXPORT_SYMBOL(rproc_add);
+
+static void devm_rproc_remove(void *rproc)
+{
+	rproc_del(rproc);
+}
+
+/**
+ * devm_rproc_add() - resource managed rproc_add()
+ * @dev: the underlying device
+ * @rproc: the remote processor handle to register
+ *
+ * This function performs like rproc_add() but the registered rproc device will
+ * automatically be removed on driver detach.
+ *
+ * Return: 0 on success, negative errno on failure
+ */
+int devm_rproc_add(struct device *dev, struct rproc *rproc)
+{
+	int err;
+
+	err = rproc_add(rproc);
+	if (err)
+		return err;
+
+	return devm_add_action_or_reset(dev, devm_rproc_remove, rproc);
+}
+EXPORT_SYMBOL(devm_rproc_add);
+
+/**
+ * rproc_type_release() - release a remote processor instance
+ * @dev: the rproc's device
+ *
+ * This function should _never_ be called directly.
+ *
+ * It will be called by the driver core when no one holds a valid pointer
+ * to @dev anymore.
+ */
+static void rproc_type_release(struct device *dev)
+{
+	struct rproc *rproc = container_of(dev, struct rproc, dev);
+
+	dev_info(&rproc->dev, "releasing %s\n", rproc->name);
+
+	idr_destroy(&rproc->notifyids);
+
+	if (rproc->index >= 0)
+		ida_free(&rproc_dev_index, rproc->index);
+
+	kfree_const(rproc->firmware);
+	kfree_const(rproc->name);
+	kfree(rproc->ops);
+	kfree(rproc);
+}
+
+static const struct device_type rproc_type = {
+	.name		= "remoteproc",
+	.release	= rproc_type_release,
+};
+
+static int rproc_alloc_firmware(struct rproc *rproc,
+				const char *name, const char *firmware)
+{
+	const char *p;
+
+	/*
+	 * Allocate a firmware name if the caller gave us one to work
+	 * with.  Otherwise construct a new one using a default pattern.
+	 */
+	if (firmware)
+		p = kstrdup_const(firmware, GFP_KERNEL);
+	else
+		p = kasprintf(GFP_KERNEL, "rproc-%s-fw", name);
+
+	if (!p)
+		return -ENOMEM;
+
+	rproc->firmware = p;
+
+	return 0;
+}
+
+static int rproc_alloc_ops(struct rproc *rproc, const struct rproc_ops *ops)
+{
+	rproc->ops = kmemdup(ops, sizeof(*ops), GFP_KERNEL);
+	if (!rproc->ops)
+		return -ENOMEM;
+
+	/* Default to rproc_coredump if no coredump function is specified */
+	if (!rproc->ops->coredump)
+		rproc->ops->coredump = rproc_coredump;
+
+	if (rproc->ops->load)
+		return 0;
+
+	/* Default to ELF loader if no load function is specified */
+	rproc->ops->load = rproc_elf_load_segments;
+	rproc->ops->parse_fw = rproc_elf_load_rsc_table;
+	rproc->ops->find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table;
+	rproc->ops->sanity_check = rproc_elf_sanity_check;
+	rproc->ops->get_boot_addr = rproc_elf_get_boot_addr;
+
+	return 0;
+}
+
+/**
+ * rproc_alloc() - allocate a remote processor handle
+ * @dev: the underlying device
+ * @name: name of this remote processor
+ * @ops: platform-specific handlers (mainly start/stop)
+ * @firmware: name of firmware file to load, can be NULL
+ * @len: length of private data needed by the rproc driver (in bytes)
+ *
+ * Allocates a new remote processor handle, but does not register
+ * it yet. if @firmware is NULL, a default name is used.
+ *
+ * This function should be used by rproc implementations during initialization
+ * of the remote processor.
+ *
+ * After creating an rproc handle using this function, and when ready,
+ * implementations should then call rproc_add() to complete
+ * the registration of the remote processor.
+ *
+ * Note: _never_ directly deallocate @rproc, even if it was not registered
+ * yet. Instead, when you need to unroll rproc_alloc(), use rproc_free().
+ *
+ * Return: new rproc pointer on success, and NULL on failure
+ */
+struct rproc *rproc_alloc(struct device *dev, const char *name,
+			  const struct rproc_ops *ops,
+			  const char *firmware, int len)
+{
+	struct rproc *rproc;
+
+	if (!dev || !name || !ops)
+		return NULL;
+
+	rproc = kzalloc(sizeof(struct rproc) + len, GFP_KERNEL);
+	if (!rproc)
+		return NULL;
+
+	rproc->priv = &rproc[1];
+	rproc->auto_boot = true;
+	rproc->elf_class = ELFCLASSNONE;
+	rproc->elf_machine = EM_NONE;
+
+	device_initialize(&rproc->dev);
+	rproc->dev.parent = dev;
+	rproc->dev.type = &rproc_type;
+	rproc->dev.class = &rproc_class;
+	rproc->dev.driver_data = rproc;
+	idr_init(&rproc->notifyids);
+
+	rproc->name = kstrdup_const(name, GFP_KERNEL);
+	if (!rproc->name)
+		goto put_device;
+
+	if (rproc_alloc_firmware(rproc, name, firmware))
+		goto put_device;
+
+	if (rproc_alloc_ops(rproc, ops))
+		goto put_device;
+
+	/* Assign a unique device index and name */
+	rproc->index = ida_alloc(&rproc_dev_index, GFP_KERNEL);
+	if (rproc->index < 0) {
+		dev_err(dev, "ida_alloc failed: %d\n", rproc->index);
+		goto put_device;
+	}
+
+	dev_set_name(&rproc->dev, "remoteproc%d", rproc->index);
+
+	atomic_set(&rproc->power, 0);
+
+	mutex_init(&rproc->lock);
+
+	INIT_LIST_HEAD(&rproc->carveouts);
+	INIT_LIST_HEAD(&rproc->mappings);
+	INIT_LIST_HEAD(&rproc->traces);
+	INIT_LIST_HEAD(&rproc->rvdevs);
+	INIT_LIST_HEAD(&rproc->subdevs);
+	INIT_LIST_HEAD(&rproc->dump_segments);
+
+	INIT_WORK(&rproc->crash_handler, rproc_crash_handler_work);
+
+	rproc->state = RPROC_OFFLINE;
+
+	return rproc;
+
+put_device:
+	put_device(&rproc->dev);
+	return NULL;
+}
+EXPORT_SYMBOL(rproc_alloc);
+
+/**
+ * rproc_free() - unroll rproc_alloc()
+ * @rproc: the remote processor handle
+ *
+ * This function decrements the rproc dev refcount.
+ *
+ * If no one holds any reference to rproc anymore, then its refcount would
+ * now drop to zero, and it would be freed.
+ */
+void rproc_free(struct rproc *rproc)
+{
+	put_device(&rproc->dev);
+}
+EXPORT_SYMBOL(rproc_free);
+
+/**
+ * rproc_put() - release rproc reference
+ * @rproc: the remote processor handle
+ *
+ * This function decrements the rproc dev refcount.
+ *
+ * If no one holds any reference to rproc anymore, then its refcount would
+ * now drop to zero, and it would be freed.
+ */
+void rproc_put(struct rproc *rproc)
+{
+	module_put(rproc->dev.parent->driver->owner);
+	put_device(&rproc->dev);
+}
+EXPORT_SYMBOL(rproc_put);
+
+/**
+ * rproc_del() - unregister a remote processor
+ * @rproc: rproc handle to unregister
+ *
+ * This function should be called when the platform specific rproc
+ * implementation decides to remove the rproc device. it should
+ * _only_ be called if a previous invocation of rproc_add()
+ * has completed successfully.
+ *
+ * After rproc_del() returns, @rproc isn't freed yet, because
+ * of the outstanding reference created by rproc_alloc. To decrement that
+ * one last refcount, one still needs to call rproc_free().
+ *
+ * Return: 0 on success and -EINVAL if @rproc isn't valid
+ */
+int rproc_del(struct rproc *rproc)
+{
+	if (!rproc)
+		return -EINVAL;
+
+	/* TODO: make sure this works with rproc->power > 1 */
+	rproc_shutdown(rproc);
+
+	mutex_lock(&rproc->lock);
+	rproc->state = RPROC_DELETED;
+	mutex_unlock(&rproc->lock);
+
+	rproc_delete_debug_dir(rproc);
+
+	/* the rproc is downref'ed as soon as it's removed from the klist */
+	mutex_lock(&rproc_list_mutex);
+	list_del_rcu(&rproc->node);
+	mutex_unlock(&rproc_list_mutex);
+
+	/* Ensure that no readers of rproc_list are still active */
+	synchronize_rcu();
+
+	device_del(&rproc->dev);
+	rproc_char_device_remove(rproc);
+
+	return 0;
+}
+EXPORT_SYMBOL(rproc_del);
+
+static void devm_rproc_free(struct device *dev, void *res)
+{
+	rproc_free(*(struct rproc **)res);
+}
+
+/**
+ * devm_rproc_alloc() - resource managed rproc_alloc()
+ * @dev: the underlying device
+ * @name: name of this remote processor
+ * @ops: platform-specific handlers (mainly start/stop)
+ * @firmware: name of firmware file to load, can be NULL
+ * @len: length of private data needed by the rproc driver (in bytes)
+ *
+ * This function performs like rproc_alloc() but the acquired rproc device will
+ * automatically be released on driver detach.
+ *
+ * Return: new rproc instance, or NULL on failure
+ */
+struct rproc *devm_rproc_alloc(struct device *dev, const char *name,
+			       const struct rproc_ops *ops,
+			       const char *firmware, int len)
+{
+	struct rproc **ptr, *rproc;
+
+	ptr = devres_alloc(devm_rproc_free, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	rproc = rproc_alloc(dev, name, ops, firmware, len);
+	if (rproc) {
+		*ptr = rproc;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return rproc;
+}
+EXPORT_SYMBOL(devm_rproc_alloc);
+
+/**
+ * rproc_add_subdev() - add a subdevice to a remoteproc
+ * @rproc: rproc handle to add the subdevice to
+ * @subdev: subdev handle to register
+ *
+ * Caller is responsible for populating optional subdevice function pointers.
+ */
+void rproc_add_subdev(struct rproc *rproc, struct rproc_subdev *subdev)
+{
+	list_add_tail(&subdev->node, &rproc->subdevs);
+}
+EXPORT_SYMBOL(rproc_add_subdev);
+
+/**
+ * rproc_remove_subdev() - remove a subdevice from a remoteproc
+ * @rproc: rproc handle to remove the subdevice from
+ * @subdev: subdev handle, previously registered with rproc_add_subdev()
+ */
+void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev)
+{
+	list_del(&subdev->node);
+}
+EXPORT_SYMBOL(rproc_remove_subdev);
+
+/**
+ * rproc_get_by_child() - acquire rproc handle of @dev's ancestor
+ * @dev:	child device to find ancestor of
+ *
+ * Return: the ancestor rproc instance, or NULL if not found
+ */
+struct rproc *rproc_get_by_child(struct device *dev)
+{
+	for (dev = dev->parent; dev; dev = dev->parent) {
+		if (dev->type == &rproc_type)
+			return dev->driver_data;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL(rproc_get_by_child);
+
+/**
+ * rproc_report_crash() - rproc crash reporter function
+ * @rproc: remote processor
+ * @type: crash type
+ *
+ * This function must be called every time a crash is detected by the low-level
+ * drivers implementing a specific remoteproc. This should not be called from a
+ * non-remoteproc driver.
+ *
+ * This function can be called from atomic/interrupt context.
+ */
+void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type)
+{
+	if (!rproc) {
+		pr_err("NULL rproc pointer\n");
+		return;
+	}
+
+	/* Prevent suspend while the remoteproc is being recovered */
+	pm_stay_awake(rproc->dev.parent);
+
+	dev_err(&rproc->dev, "crash detected in %s: type %s\n",
+		rproc->name, rproc_crash_to_string(type));
+
+	queue_work(rproc_recovery_wq, &rproc->crash_handler);
+}
+EXPORT_SYMBOL(rproc_report_crash);
+
+static int rproc_panic_handler(struct notifier_block *nb, unsigned long event,
+			       void *ptr)
+{
+	unsigned int longest = 0;
+	struct rproc *rproc;
+	unsigned int d;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(rproc, &rproc_list, node) {
+		if (!rproc->ops->panic)
+			continue;
+
+		if (rproc->state != RPROC_RUNNING &&
+		    rproc->state != RPROC_ATTACHED)
+			continue;
+
+		d = rproc->ops->panic(rproc);
+		longest = max(longest, d);
+	}
+	rcu_read_unlock();
+
+	/*
+	 * Delay for the longest requested duration before returning. This can
+	 * be used by the remoteproc drivers to give the remote processor time
+	 * to perform any requested operations (such as flush caches), when
+	 * it's not possible to signal the Linux side due to the panic.
+	 */
+	mdelay(longest);
+
+	return NOTIFY_DONE;
+}
+
+static void __init rproc_init_panic(void)
+{
+	rproc_panic_nb.notifier_call = rproc_panic_handler;
+	atomic_notifier_chain_register(&panic_notifier_list, &rproc_panic_nb);
+}
+
+static void __exit rproc_exit_panic(void)
+{
+	atomic_notifier_chain_unregister(&panic_notifier_list, &rproc_panic_nb);
+}
+
+static int __init remoteproc_init(void)
+{
+	rproc_recovery_wq = alloc_workqueue("rproc_recovery_wq",
+						WQ_UNBOUND | WQ_FREEZABLE, 0);
+	if (!rproc_recovery_wq) {
+		pr_err("remoteproc: creation of rproc_recovery_wq failed\n");
+		return -ENOMEM;
+	}
+
+	rproc_init_sysfs();
+	rproc_init_debugfs();
+	rproc_init_cdev();
+	rproc_init_panic();
+
+	return 0;
+}
+subsys_initcall(remoteproc_init);
+
+static void __exit remoteproc_exit(void)
+{
+	ida_destroy(&rproc_dev_index);
+
+	if (!rproc_recovery_wq)
+		return;
+
+	rproc_exit_panic();
+	rproc_exit_debugfs();
+	rproc_exit_sysfs();
+	destroy_workqueue(rproc_recovery_wq);
+}
+module_exit(remoteproc_exit);
+
+MODULE_DESCRIPTION("Generic Remote Processor Framework");