6 files changed, 1466 insertions, 0 deletions

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 5afe5d1f199b..27b34bf41d4c 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -132,6 +132,8 @@ source "drivers/clocksource/Kconfig"
 
 source "drivers/iommu/Kconfig"
 
+source "drivers/remoteproc/Kconfig"
+
 source "drivers/virt/Kconfig"
 
 source "drivers/devfreq/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index c07be024b962..f1019b714f27 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -126,6 +126,7 @@ obj-y				+= clk/
 obj-$(CONFIG_HWSPINLOCK)        += hwspinlock/
 obj-$(CONFIG_NFC)               += nfc/
 obj-$(CONFIG_IOMMU_SUPPORT)     += iommu/
+obj-$(CONFIG_REMOTEPROC)        += remoteproc/
 
 # Virtualization drivers
 obj-$(CONFIG_VIRT_DRIVERS)      += virt/
diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
new file mode 100644
index 000000000000..b250b15c0686
--- /dev/null
+++ b/drivers/remoteproc/Kconfig
@@ -0,0 +1,3 @@
+# REMOTEPROC gets selected by whoever wants it
+config REMOTEPROC
+        tristate
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
new file mode 100644
index 000000000000..2a5fd7992f5a
--- /dev/null
+++ b/drivers/remoteproc/Makefile
@@ -0,0 +1,6 @@
+#
+# Generic framework for controlling remote processors
+#
+
+obj-$(CONFIG_REMOTEPROC)                += remoteproc.o
+remoteproc-y                            := remoteproc_core.o
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
new file mode 100644
index 000000000000..ad93d7d4ecbb
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -0,0 +1,1410 @@
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt)    "%s: " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.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/remoteproc.h>
+#include <linux/iommu.h>
+#include <linux/klist.h>
+#include <linux/elf.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_ring.h>
+
+#include "remoteproc_internal.h"
+
+static void klist_rproc_get(struct klist_node *n);
+static void klist_rproc_put(struct klist_node *n);
+
+/*
+ * klist of the available remote processors.
+ *
+ * We need this in order to support name-based lookups (needed by the
+ * rproc_get_by_name()).
+ *
+ * That said, we don't use rproc_get_by_name() anymore within the rpmsg
+ * framework. The use cases that do require its existence should be
+ * scrutinized, and hopefully migrated to rproc_boot() using device-based
+ * binding.
+ *
+ * If/when this materializes, we could drop the klist (and the by_name
+ * API).
+ */
+static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put);
+
+typedef int (*rproc_handle_resources_t)(struct rproc *rproc,
+                                struct fw_resource *rsc, int len);
+
+/*
+ * 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.
+ *
+ * Currently this is mostly a stub, but it will be later used to trigger
+ * the recovery of the remote processor.
+ */
+static int rproc_iommu_fault(struct iommu_domain *domain, struct device *dev,
+                unsigned long iova, int flags)
+{
+        dev_err(dev, "iommu fault: da 0x%lx flags 0x%x\n", iova, flags);
+
+        /*
+         * Let the iommu core know we're not really handling this fault;
+         * we just plan to use this as a recovery trigger.
+         */
+        return -ENOSYS;
+}
+
+static int rproc_enable_iommu(struct rproc *rproc)
+{
+        struct iommu_domain *domain;
+        struct device *dev = rproc->dev;
+        int ret;
+
+        /*
+         * We currently use iommu_present() to decide if an IOMMU
+         * setup is needed.
+         *
+         * This works for simple cases, but will easily fail with
+         * platforms that do have an IOMMU, but not for this specific
+         * rproc.
+         *
+         * This will be easily solved by introducing hw capabilities
+         * that will be set by the remoteproc driver.
+         */
+        if (!iommu_present(dev->bus)) {
+                dev_err(dev, "iommu not found\n");
+                return -ENODEV;
+        }
+
+        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);
+
+        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;
+
+        if (!domain)
+                return;
+
+        iommu_detach_device(domain, dev);
+        iommu_domain_free(domain);
+
+        return;
+}
+
+/*
+ * 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 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 an internal helper with which we can go over the allocated
+ * carveouts and translate specific device address to kernel virtual addresses
+ * so we can access the referenced memory.
+ *
+ * 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, which should be more correct.
+ */
+static void *rproc_da_to_va(struct rproc *rproc, u64 da, int len)
+{
+        struct rproc_mem_entry *carveout;
+        void *ptr = NULL;
+
+        list_for_each_entry(carveout, &rproc->carveouts, node) {
+                int offset = da - carveout->da;
+
+                /* 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;
+
+                break;
+        }
+
+        return ptr;
+}
+
+/**
+ * rproc_load_segments() - load firmware segments to memory
+ * @rproc: remote processor which will be booted using these fw segments
+ * @elf_data: the content of the ELF firmware image
+ *
+ * This function loads the firmware segments to memory, where the remote
+ * processor expects them.
+ *
+ * Some remote processors will expect their code and data to be placed
+ * in specific device addresses, and can't have them dynamically assigned.
+ *
+ * We currently support only those kind of remote processors, and expect
+ * the program header's paddr member to contain those addresses. We then go
+ * through the physically contiguous "carveout" memory regions which we
+ * allocated (and mapped) earlier on behalf of the remote processor,
+ * and "translate" device address to kernel addresses, so we can copy the
+ * segments where they are expected.
+ *
+ * Currently we only support remote processors that required carveout
+ * allocations and got them mapped onto their iommus. Some processors
+ * might be different: they might not have iommus, and would prefer to
+ * directly allocate memory for every segment/resource. This is not yet
+ * supported, though.
+ */
+static int rproc_load_segments(struct rproc *rproc, const u8 *elf_data)
+{
+        struct device *dev = rproc->dev;
+        struct elf32_hdr *ehdr;
+        struct elf32_phdr *phdr;
+        int i, ret = 0;
+
+        ehdr = (struct elf32_hdr *)elf_data;
+        phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff);
+
+        /* go through the available ELF segments */
+        for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
+                u32 da = phdr->p_paddr;
+                u32 memsz = phdr->p_memsz;
+                u32 filesz = phdr->p_filesz;
+                void *ptr;
+
+                if (phdr->p_type != PT_LOAD)
+                        continue;
+
+                dev_dbg(dev, "phdr: type %d da 0x%x memsz 0x%x filesz 0x%x\n",
+                                        phdr->p_type, da, memsz, filesz);
+
+                if (filesz > memsz) {
+                        dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n",
+                                                        filesz, memsz);
+                        ret = -EINVAL;
+                        break;
+                }
+
+                /* grab the kernel address for this device address */
+                ptr = rproc_da_to_va(rproc, da, memsz);
+                if (!ptr) {
+                        dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz);
+                        ret = -EINVAL;
+                        break;
+                }
+
+                /* put the segment where the remote processor expects it */
+                if (phdr->p_filesz)
+                        memcpy(ptr, elf_data + phdr->p_offset, filesz);
+
+                /*
+                 * Zero out remaining memory for this segment.
+                 *
+                 * This isn't strictly required since dma_alloc_coherent already
+                 * did this for us. albeit harmless, we may consider removing
+                 * this.
+                 */
+                if (memsz > filesz)
+                        memset(ptr + filesz, 0, memsz - filesz);
+        }
+
+        return ret;
+}
+
+/**
+ * rproc_handle_virtio_hdr() - handle a virtio header resource
+ * @rproc: the remote processor
+ * @rsc: the resource descriptor
+ *
+ * The existence of this virtio hdr resource entry means that the firmware
+ * of this @rproc supports this virtio device.
+ *
+ * Currently we support only a single virtio device of type VIRTIO_ID_RPMSG,
+ * but the plan is to remove this limitation and support any number
+ * of virtio devices (and of any type). We'll also add support for dynamically
+ * adding (and removing) virtio devices over the rpmsg bus, but small
+ * firmwares that doesn't want to get involved with rpmsg will be able
+ * to simple use the resource table for this.
+ *
+ * At this point this virtio header entry is rather simple: it just
+ * announces the virtio device id and the supported virtio device features.
+ * The plan though is to extend this to include the vring information and
+ * the virtio config space, too (but first, some resource table overhaul
+ * is needed: move from fixed-sized to variable-length TLV entries).
+ *
+ * For now, the 'flags' member of the resource entry contains the virtio
+ * device id, the 'da' member contains the device features, and 'pa' is
+ * where we need to store the guest features once negotiation completes.
+ * As usual, the 'id' member of this resource contains the index of this
+ * resource type (i.e. is this the first virtio hdr entry, the 2nd, ...).
+ *
+ * Returns 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc)
+{
+        struct rproc_vdev *rvdev;
+
+        /* we only support VIRTIO_ID_RPMSG devices for now */
+        if (rsc->flags != VIRTIO_ID_RPMSG) {
+                dev_warn(rproc->dev, "unsupported vdev: %d\n", rsc->flags);
+                return -EINVAL;
+        }
+
+        /* we only support a single vdev per rproc for now */
+        if (rsc->id || rproc->rvdev) {
+                dev_warn(rproc->dev, "redundant vdev entry: %s\n", rsc->name);
+                return -EINVAL;
+        }
+
+        rvdev = kzalloc(sizeof(struct rproc_vdev), GFP_KERNEL);
+        if (!rvdev)
+                return -ENOMEM;
+
+        /* remember the device features */
+        rvdev->dfeatures = rsc->da;
+
+        rproc->rvdev = rvdev;
+        rvdev->rproc = rproc;
+
+        return 0;
+}
+
+/**
+ * rproc_handle_vring() - handle a vring fw resource
+ * @rproc: the remote processor
+ * @rsc: the vring resource descriptor
+ *
+ * This resource entry requires allocation of non-cacheable memory
+ * for a virtio vring. Currently we only support two vrings per remote
+ * processor, required for the virtio rpmsg device.
+ *
+ * The 'len' member of @rsc should contain the number of buffers this vring
+ * support and 'da' should either contain the device address where
+ * the remote processor is expecting the vring, or indicate that
+ * dynamically allocation of the vring's device address is supported.
+ *
+ * Note: 'da' is currently not handled. This will be revised when the generic
+ * iommu-based DMA API will arrive, or a dynanic & non-iommu use case show
+ * up. Meanwhile, statically-addressed iommu-based images should use
+ * RSC_DEVMEM resource entries to map their require 'da' to the physical
+ * address of their base CMA region.
+ *
+ * Returns 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_vring(struct rproc *rproc, struct fw_resource *rsc)
+{
+        struct device *dev = rproc->dev;
+        struct rproc_vdev *rvdev = rproc->rvdev;
+        dma_addr_t dma;
+        int size, id = rsc->id;
+        void *va;
+
+        /* no vdev is in place ? */
+        if (!rvdev) {
+                dev_err(dev, "vring requested without a virtio dev entry\n");
+                return -EINVAL;
+        }
+
+        /* the firmware must provide the expected queue size */
+        if (!rsc->len) {
+                dev_err(dev, "missing expected queue size\n");
+                return -EINVAL;
+        }
+
+        /* we currently support two vrings per rproc (for rx and tx) */
+        if (id >= ARRAY_SIZE(rvdev->vring)) {
+                dev_err(dev, "%s: invalid vring id %d\n", rsc->name, id);
+                return -EINVAL;
+        }
+
+        /* have we already allocated this vring id ? */
+        if (rvdev->vring[id].len) {
+                dev_err(dev, "%s: duplicated id %d\n", rsc->name, id);
+                return -EINVAL;
+        }
+
+        /* actual size of vring (in bytes) */
+        size = PAGE_ALIGN(vring_size(rsc->len, AMP_VRING_ALIGN));
+
+        /*
+         * Allocate non-cacheable memory for the vring. In the future
+         * this call will also configure the IOMMU for us
+         */
+        va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL);
+        if (!va) {
+                dev_err(dev, "dma_alloc_coherent failed\n");
+                return -ENOMEM;
+        }
+
+        dev_dbg(dev, "vring%d: va %p dma %x qsz %d ring size %x\n", id, va,
+                                        dma, rsc->len, size);
+
+        rvdev->vring[id].len = rsc->len;
+        rvdev->vring[id].va = va;
+        rvdev->vring[id].dma = dma;
+
+        return 0;
+}
+
+/**
+ * rproc_handle_trace() - handle a shared trace buffer resource
+ * @rproc: the remote processor
+ * @rsc: the trace resource descriptor
+ *
+ * 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).
+ *
+ * Returns 0 on success, or an appropriate error code otherwise
+ */
+static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc)
+{
+        struct rproc_mem_entry *trace;
+        struct device *dev = rproc->dev;
+        void *ptr;
+        char name[15];
+
+        /* what's the kernel address of this resource ? */
+        ptr = rproc_da_to_va(rproc, rsc->da, rsc->len);
+        if (!ptr) {
+                dev_err(dev, "erroneous trace resource entry\n");
+                return -EINVAL;
+        }
+
+        trace = kzalloc(sizeof(*trace), GFP_KERNEL);
+        if (!trace) {
+                dev_err(dev, "kzalloc trace failed\n");
+                return -ENOMEM;
+        }
+
+        /* set the trace buffer dma properties */
+        trace->len = rsc->len;
+        trace->va = ptr;
+
+        /* make sure snprintf always null terminates, even if truncating */
+        snprintf(name, sizeof(name), "trace%d", rproc->num_traces);
+
+        /* create the debugfs entry */
+        trace->priv = rproc_create_trace_file(name, rproc, trace);
+        if (!trace->priv) {
+                trace->va = NULL;
+                kfree(trace);
+                return -EINVAL;
+        }
+
+        list_add_tail(&trace->node, &rproc->traces);
+
+        rproc->num_traces++;
+
+        dev_dbg(dev, "%s added: va %p, da 0x%llx, len 0x%x\n", name, ptr,
+                                                rsc->da, rsc->len);
+
+        return 0;
+}
+
+/**
+ * rproc_handle_devmem() - handle devmem resource entry
+ * @rproc: remote processor handle
+ * @rsc: the devmem resource entry
+ *
+ * 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.
+ */
+static int rproc_handle_devmem(struct rproc *rproc, struct fw_resource *rsc)
+{
+        struct rproc_mem_entry *mapping;
+        int ret;
+
+        /* no point in handling this resource without a valid iommu domain */
+        if (!rproc->domain)
+                return -EINVAL;
+
+        mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
+        if (!mapping) {
+                dev_err(rproc->dev, "kzalloc mapping failed\n");
+                return -ENOMEM;
+        }
+
+        ret = iommu_map(rproc->domain, rsc->da, rsc->pa, rsc->len, rsc->flags);
+        if (ret) {
+                dev_err(rproc->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(rproc->dev, "mapped devmem pa 0x%llx, da 0x%llx, len 0x%x\n",
+                                        rsc->pa, rsc->da, rsc->len);
+
+        return 0;
+
+out:
+        kfree(mapping);
+        return ret;
+}
+
+/**
+ * rproc_handle_carveout() - handle phys contig memory allocation requests
+ * @rproc: rproc handle
+ * @rsc: the resource entry
+ *
+ * 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.
+ */
+static int rproc_handle_carveout(struct rproc *rproc, struct fw_resource *rsc)
+{
+        struct rproc_mem_entry *carveout, *mapping;
+        struct device *dev = rproc->dev;
+        dma_addr_t dma;
+        void *va;
+        int ret;
+
+        mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
+        if (!mapping) {
+                dev_err(dev, "kzalloc mapping failed\n");
+                return -ENOMEM;
+        }
+
+        carveout = kzalloc(sizeof(*carveout), GFP_KERNEL);
+        if (!carveout) {
+                dev_err(dev, "kzalloc carveout failed\n");
+                ret = -ENOMEM;
+                goto free_mapping;
+        }
+
+        va = dma_alloc_coherent(dev, rsc->len, &dma, GFP_KERNEL);
+        if (!va) {
+                dev_err(dev, "failed to dma alloc carveout: %d\n", rsc->len);
+                ret = -ENOMEM;
+                goto free_carv;
+        }
+
+        dev_dbg(dev, "carveout va %p, dma %x, len 0x%x\n", va, dma, rsc->len);
+
+        /*
+         * 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 (rproc->domain) {
+                ret = iommu_map(rproc->domain, rsc->da, dma, rsc->len,
+                                                                rsc->flags);
+                if (ret) {
+                        dev_err(dev, "iommu_map failed: %d\n", ret);
+                        goto dma_free;
+                }
+
+                /*
+                 * 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, "carveout mapped 0x%llx to 0x%x\n", rsc->da, dma);
+
+                /*
+                 * 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).
+                 */
+                rsc->pa = dma;
+        }
+
+        carveout->va = va;
+        carveout->len = rsc->len;
+        carveout->dma = dma;
+        carveout->da = rsc->da;
+
+        list_add_tail(&carveout->node, &rproc->carveouts);
+
+        return 0;
+
+dma_free:
+        dma_free_coherent(dev, rsc->len, va, dma);
+free_carv:
+        kfree(carveout);
+free_mapping:
+        kfree(mapping);
+        return ret;
+}
+
+/* handle firmware resource entries before booting the remote processor */
+static int
+rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len)
+{
+        struct device *dev = rproc->dev;
+        int ret = 0;
+
+        while (len >= sizeof(*rsc)) {
+                dev_dbg(dev, "rsc: type %d, da 0x%llx, pa 0x%llx, len 0x%x, "
+                        "id %d, name %s, flags %x\n", rsc->type, rsc->da,
+                        rsc->pa, rsc->len, rsc->id, rsc->name, rsc->flags);
+
+                switch (rsc->type) {
+                case RSC_CARVEOUT:
+                        ret = rproc_handle_carveout(rproc, rsc);
+                        break;
+                case RSC_DEVMEM:
+                        ret = rproc_handle_devmem(rproc, rsc);
+                        break;
+                case RSC_TRACE:
+                        ret = rproc_handle_trace(rproc, rsc);
+                        break;
+                case RSC_VRING:
+                        ret = rproc_handle_vring(rproc, rsc);
+                        break;
+                case RSC_VIRTIO_DEV:
+                        /* this one is handled early upon registration */
+                        break;
+                default:
+                        dev_warn(dev, "unsupported resource %d\n", rsc->type);
+                        break;
+                }
+
+                if (ret)
+                        break;
+
+                rsc++;
+                len -= sizeof(*rsc);
+        }
+
+        return ret;
+}
+
+/* handle firmware resource entries while registering the remote processor */
+static int
+rproc_handle_virtio_rsc(struct rproc *rproc, struct fw_resource *rsc, int len)
+{
+        struct device *dev = rproc->dev;
+        int ret = 0;
+
+        for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc))
+                if (rsc->type == RSC_VIRTIO_DEV) {
+                        dev_dbg(dev, "found vdev %d/%s features %llx\n",
+                                        rsc->flags, rsc->name, rsc->da);
+                        ret = rproc_handle_virtio_hdr(rproc, rsc);
+                        break;
+                }
+
+        return ret;
+}
+
+/**
+ * rproc_handle_resources() - find and handle the resource table
+ * @rproc: the rproc handle
+ * @elf_data: the content of the ELF firmware image
+ * @handler: function that should be used to handle the resource table
+ *
+ * This function finds the resource table inside the remote processor's
+ * firmware, and invoke a user-supplied handler with it (we have two
+ * possible handlers: one is invoked upon registration of @rproc,
+ * in order to register the supported virito devices, and the other is
+ * invoked when @rproc is actually booted).
+ *
+ * Currently this function fails if a resource table doesn't exist.
+ * This restriction will be removed when we'll start supporting remote
+ * processors that don't need a resource table.
+ */
+static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data,
+                                        rproc_handle_resources_t handler)
+
+{
+        struct elf32_hdr *ehdr;
+        struct elf32_shdr *shdr;
+        const char *name_table;
+        int i, ret = -EINVAL;
+
+        ehdr = (struct elf32_hdr *)elf_data;
+        shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff);
+        name_table = elf_data + shdr[ehdr->e_shstrndx].sh_offset;
+
+        /* look for the resource table and handle it */
+        for (i = 0; i < ehdr->e_shnum; i++, shdr++) {
+                if (!strcmp(name_table + shdr->sh_name, ".resource_table")) {
+                        struct fw_resource *table = (struct fw_resource *)
+                                                (elf_data + shdr->sh_offset);
+
+                        ret = handler(rproc, table, shdr->sh_size);
+
+                        break;
+                }
+        }
+
+        return ret;
+}
+
+/**
+ * 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 when @rproc shuts down, or just failed booting.
+ */
+static void rproc_resource_cleanup(struct rproc *rproc)
+{
+        struct rproc_mem_entry *entry, *tmp;
+        struct device *dev = rproc->dev;
+        struct rproc_vdev *rvdev = rproc->rvdev;
+        int i;
+
+        /* clean up debugfs trace entries */
+        list_for_each_entry_safe(entry, tmp, &rproc->traces, node) {
+                rproc_remove_trace_file(entry->priv);
+                rproc->num_traces--;
+                list_del(&entry->node);
+                kfree(entry);
+        }
+
+        /* free the coherent memory allocated for the vrings */
+        for (i = 0; rvdev && i < ARRAY_SIZE(rvdev->vring); i++) {
+                int qsz = rvdev->vring[i].len;
+                void *va = rvdev->vring[i].va;
+                int dma = rvdev->vring[i].dma;
+
+                /* virtqueue size is expressed in number of buffers supported */
+                if (qsz) {
+                        /* how many bytes does this vring really occupy ? */
+                        int size = PAGE_ALIGN(vring_size(qsz, AMP_VRING_ALIGN));
+
+                        dma_free_coherent(rproc->dev, size, va, dma);
+
+                        rvdev->vring[i].len = 0;
+                }
+        }
+
+        /* clean up carveout allocations */
+        list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
+                dma_free_coherent(dev, entry->len, entry->va, entry->dma);
+                list_del(&entry->node);
+                kfree(entry);
+        }
+
+        /* 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 %u/%u\n", entry->len,
+                                                                unmapped);
+                }
+
+                list_del(&entry->node);
+                kfree(entry);
+        }
+}
+
+/* make sure this fw image is sane */
+static int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw)
+{
+        const char *name = rproc->firmware;
+        struct device *dev = rproc->dev;
+        struct elf32_hdr *ehdr;
+
+        if (!fw) {
+                dev_err(dev, "failed to load %s\n", name);
+                return -EINVAL;
+        }
+
+        if (fw->size < sizeof(struct elf32_hdr)) {
+                dev_err(dev, "Image is too small\n");
+                return -EINVAL;
+        }
+
+        ehdr = (struct elf32_hdr *)fw->data;
+
+        if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
+                dev_err(dev, "Image is corrupted (bad magic)\n");
+                return -EINVAL;
+        }
+
+        if (ehdr->e_phnum == 0) {
+                dev_err(dev, "No loadable segments\n");
+                return -EINVAL;
+        }
+
+        if (ehdr->e_phoff > fw->size) {
+                dev_err(dev, "Firmware size is too small\n");
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+/*
+ * 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;
+        struct elf32_hdr *ehdr;
+        int ret;
+
+        ret = rproc_fw_sanity_check(rproc, fw);
+        if (ret)
+                return ret;
+
+        ehdr = (struct elf32_hdr *)fw->data;
+
+        dev_info(dev, "Booting fw image %s, size %d\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;
+        }
+
+        /*
+         * The ELF entry point is the rproc's boot addr (though this is not
+         * a configurable property of all remote processors: some will always
+         * boot at a specific hardcoded address).
+         */
+        rproc->bootaddr = ehdr->e_entry;
+
+        /* handle fw resources which are required to boot rproc */
+        ret = rproc_handle_resources(rproc, fw->data, rproc_handle_boot_rsc);
+        if (ret) {
+                dev_err(dev, "Failed to process resources: %d\n", ret);
+                goto clean_up;
+        }
+
+        /* load the ELF segments to memory */
+        ret = rproc_load_segments(rproc, fw->data);
+        if (ret) {
+                dev_err(dev, "Failed to load program segments: %d\n", ret);
+                goto clean_up;
+        }
+
+        /* 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 clean_up;
+        }
+
+        rproc->state = RPROC_RUNNING;
+
+        dev_info(dev, "remote processor %s is now up\n", rproc->name);
+
+        return 0;
+
+clean_up:
+        rproc_resource_cleanup(rproc);
+        rproc_disable_iommu(rproc);
+        return ret;
+}
+
+/*
+ * take a firmware and look for virtio devices to register.
+ *
+ * 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_fw_config_virtio(const struct firmware *fw, void *context)
+{
+        struct rproc *rproc = context;
+        struct device *dev = rproc->dev;
+        int ret;
+
+        if (rproc_fw_sanity_check(rproc, fw) < 0)
+                goto out;
+
+        /* does the fw supports any virtio devices ? */
+        ret = rproc_handle_resources(rproc, fw->data, rproc_handle_virtio_rsc);
+        if (ret) {
+                dev_info(dev, "No fw virtio device was found\n");
+                goto out;
+        }
+
+        /* add the virtio device (currently only rpmsg vdevs are supported) */
+        ret = rproc_add_rpmsg_vdev(rproc);
+        if (ret)
+                goto out;
+
+out:
+        if (fw)
+                release_firmware(fw);
+        /* allow rproc_unregister() contexts, if any, to proceed */
+        complete_all(&rproc->firmware_loading_complete);
+}
+
+/**
+ * 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).
+ *
+ * Returns 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;
+        }
+
+        /* loading a firmware is required */
+        if (!rproc->firmware) {
+                dev_err(dev, "%s: no firmware to load\n", __func__);
+                ret = -EINVAL;
+                goto unlock_mutex;
+        }
+
+        /* prevent underlying implementation from being removed */
+        if (!try_module_get(dev->driver->owner)) {
+                dev_err(dev, "%s: can't get owner\n", __func__);
+                ret = -EINVAL;
+                goto unlock_mutex;
+        }
+
+        /* skip the boot process if rproc is already powered up */
+        if (atomic_inc_return(&rproc->power) > 1) {
+                ret = 0;
+                goto unlock_mutex;
+        }
+
+        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) {
+                module_put(dev->driver->owner);
+                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.
+ * - don't call rproc_shutdown() to unroll rproc_get_by_name(), exactly
+ *   because rproc_shutdown() _does not_ decrement the refcount of @rproc.
+ *   To decrement the refcount of @rproc, use rproc_put() (but _only_ if
+ *   you acquired @rproc using rproc_get_by_name()).
+ */
+void rproc_shutdown(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;
+        }
+
+        /* if the remote proc is still needed, bail out */
+        if (!atomic_dec_and_test(&rproc->power))
+                goto out;
+
+        /* power off the remote processor */
+        ret = rproc->ops->stop(rproc);
+        if (ret) {
+                atomic_inc(&rproc->power);
+                dev_err(dev, "can't stop rproc: %d\n", ret);
+                goto out;
+        }
+
+        /* clean up all acquired resources */
+        rproc_resource_cleanup(rproc);
+
+        rproc_disable_iommu(rproc);
+
+        rproc->state = RPROC_OFFLINE;
+
+        dev_info(dev, "stopped remote processor %s\n", rproc->name);
+
+out:
+        mutex_unlock(&rproc->lock);
+        if (!ret)
+                module_put(dev->driver->owner);
+}
+EXPORT_SYMBOL(rproc_shutdown);
+
+/**
+ * rproc_release() - completely deletes the existence of a remote processor
+ * @kref: the rproc's kref
+ *
+ * This function should _never_ be called directly.
+ *
+ * The only reasonable location to use it is as an argument when kref_put'ing
+ * @rproc's refcount.
+ *
+ * This way it will be called when no one holds a valid pointer to this @rproc
+ * anymore (and obviously after it is removed from the rprocs klist).
+ *
+ * Note: this function is not static because rproc_vdev_release() needs it when
+ * it decrements @rproc's refcount.
+ */
+void rproc_release(struct kref *kref)
+{
+        struct rproc *rproc = container_of(kref, struct rproc, refcount);
+
+        dev_info(rproc->dev, "removing %s\n", rproc->name);
+
+        rproc_delete_debug_dir(rproc);
+
+        /* at this point no one holds a reference to rproc anymore */
+        kfree(rproc);
+}
+
+/* will be called when an rproc is added to the rprocs klist */
+static void klist_rproc_get(struct klist_node *n)
+{
+        struct rproc *rproc = container_of(n, struct rproc, node);
+
+        kref_get(&rproc->refcount);
+}
+
+/* will be called when an rproc is removed from the rprocs klist */
+static void klist_rproc_put(struct klist_node *n)
+{
+        struct rproc *rproc = container_of(n, struct rproc, node);
+
+        kref_put(&rproc->refcount, rproc_release);
+}
+
+static struct rproc *next_rproc(struct klist_iter *i)
+{
+        struct klist_node *n;
+
+        n = klist_next(i);
+        if (!n)
+                return NULL;
+
+        return container_of(n, struct rproc, node);
+}
+
+/**
+ * rproc_get_by_name() - find a remote processor by name and boot it
+ * @name: name of the remote processor
+ *
+ * Finds an rproc handle using the remote processor's name, and then
+ * boot it. If it's already powered on, then just immediately return
+ * (successfully).
+ *
+ * Returns the rproc handle on success, and NULL on failure.
+ *
+ * This function increments the remote processor's refcount, so always
+ * use rproc_put() to decrement it back once rproc isn't needed anymore.
+ *
+ * Note: currently this function (and its counterpart rproc_put()) are not
+ * used anymore by the rpmsg subsystem. We need to scrutinize the use cases
+ * that still need them, and see if we can migrate them to use the non
+ * name-based boot/shutdown interface.
+ */
+struct rproc *rproc_get_by_name(const char *name)
+{
+        struct rproc *rproc;
+        struct klist_iter i;
+        int ret;
+
+        /* find the remote processor, and upref its refcount */
+        klist_iter_init(&rprocs, &i);
+        while ((rproc = next_rproc(&i)) != NULL)
+                if (!strcmp(rproc->name, name)) {
+                        kref_get(&rproc->refcount);
+                        break;
+                }
+        klist_iter_exit(&i);
+
+        /* can't find this rproc ? */
+        if (!rproc) {
+                pr_err("can't find remote processor %s\n", name);
+                return NULL;
+        }
+
+        ret = rproc_boot(rproc);
+        if (ret < 0) {
+                kref_put(&rproc->refcount, rproc_release);
+                return NULL;
+        }
+
+        return rproc;
+}
+EXPORT_SYMBOL(rproc_get_by_name);
+
+/**
+ * rproc_put() - decrement the refcount of a remote processor, and shut it down
+ * @rproc: the remote processor
+ *
+ * This function tries to shutdown @rproc, and it then decrements its
+ * refcount.
+ *
+ * After this function returns, @rproc may _not_ be used anymore, and its
+ * handle should be considered invalid.
+ *
+ * This function should be called _iff_ the @rproc handle was grabbed by
+ * calling rproc_get_by_name().
+ */
+void rproc_put(struct rproc *rproc)
+{
+        /* try to power off the remote processor */
+        rproc_shutdown(rproc);
+
+        /* downref rproc's refcount */
+        kref_put(&rproc->refcount, rproc_release);
+}
+EXPORT_SYMBOL(rproc_put);
+
+/**
+ * rproc_register() - 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.
+ *
+ * Returns 0 on success and an appropriate error code otherwise.
+ *
+ * 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 will be
+ * probed.
+ *
+ * Currently, though, we only support a single RPMSG virtio vdev per remote
+ * processor.
+ */
+int rproc_register(struct rproc *rproc)
+{
+        struct device *dev = rproc->dev;
+        int ret = 0;
+
+        /* expose to rproc_get_by_name users */
+        klist_add_tail(&rproc->node, &rprocs);
+
+        dev_info(rproc->dev, "%s is available\n", rproc->name);
+
+        /* create debugfs entries */
+        rproc_create_debug_dir(rproc);
+
+        /* rproc_unregister() calls must wait until async loader completes */
+        init_completion(&rproc->firmware_loading_complete);
+
+        /*
+         * We must retrieve early virtio configuration info from
+         * the firmware (e.g. whether to register a virtio rpmsg device,
+         * what virtio features does it support, ...).
+         *
+         * 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_HOTPLUG,
+                                        rproc->firmware, dev, GFP_KERNEL,
+                                        rproc, rproc_fw_config_virtio);
+        if (ret < 0) {
+                dev_err(dev, "request_firmware_nowait failed: %d\n", ret);
+                complete_all(&rproc->firmware_loading_complete);
+                klist_remove(&rproc->node);
+        }
+
+        return ret;
+}
+EXPORT_SYMBOL(rproc_register);
+
+/**
+ * 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
+ * @len: length of private data needed by the rproc driver (in bytes)
+ *
+ * Allocates a new remote processor handle, but does not register
+ * it yet.
+ *
+ * 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_register() to complete
+ * the registration of the remote processor.
+ *
+ * On success the new rproc is returned, and on failure, NULL.
+ *
+ * Note: _never_ directly deallocate @rproc, even if it was not registered
+ * yet. Instead, if you just need to unroll rproc_alloc(), use rproc_free().
+ */
+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) {
+                dev_err(dev, "%s: kzalloc failed\n", __func__);
+                return NULL;
+        }
+
+        rproc->dev = dev;
+        rproc->name = name;
+        rproc->ops = ops;
+        rproc->firmware = firmware;
+        rproc->priv = &rproc[1];
+
+        atomic_set(&rproc->power, 0);
+
+        kref_init(&rproc->refcount);
+
+        mutex_init(&rproc->lock);
+
+        INIT_LIST_HEAD(&rproc->carveouts);
+        INIT_LIST_HEAD(&rproc->mappings);
+        INIT_LIST_HEAD(&rproc->traces);
+
+        rproc->state = RPROC_OFFLINE;
+
+        return rproc;
+}
+EXPORT_SYMBOL(rproc_alloc);
+
+/**
+ * rproc_free() - free an rproc handle that was allocated by rproc_alloc
+ * @rproc: the remote processor handle
+ *
+ * This function should _only_ be used if @rproc was only allocated,
+ * but not registered yet.
+ *
+ * If @rproc was already successfully registered (by calling rproc_register()),
+ * then use rproc_unregister() instead.
+ */
+void rproc_free(struct rproc *rproc)
+{
+        kfree(rproc);
+}
+EXPORT_SYMBOL(rproc_free);
+
+/**
+ * rproc_unregister() - unregister a remote processor
+ * @rproc: rproc handle to unregister
+ *
+ * Unregisters a remote processor, and decrements its refcount.
+ * If its refcount drops to zero, then @rproc will be freed. If not,
+ * it will be freed later once the last reference is dropped.
+ *
+ * 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_register()
+ * has completed successfully.
+ *
+ * After rproc_unregister() returns, @rproc is _not_ valid anymore and
+ * it shouldn't be used. More specifically, don't call rproc_free()
+ * or try to directly free @rproc after rproc_unregister() returns;
+ * none of these are needed, and calling them is a bug.
+ *
+ * Returns 0 on success and -EINVAL if @rproc isn't valid.
+ */
+int rproc_unregister(struct rproc *rproc)
+{
+        if (!rproc)
+                return -EINVAL;
+
+        /* if rproc is just being registered, wait */
+        wait_for_completion(&rproc->firmware_loading_complete);
+
+        /* was an rpmsg vdev created ? */
+        if (rproc->rvdev)
+                rproc_remove_rpmsg_vdev(rproc);
+
+        klist_remove(&rproc->node);
+
+        kref_put(&rproc->refcount, rproc_release);
+
+        return 0;
+}
+EXPORT_SYMBOL(rproc_unregister);
+
+static int __init remoteproc_init(void)
+{
+        rproc_init_debugfs();
+        return 0;
+}
+module_init(remoteproc_init);
+
+static void __exit remoteproc_exit(void)
+{
+        rproc_exit_debugfs();
+}
+module_exit(remoteproc_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Generic Remote Processor Framework");
diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
new file mode 100644
index 000000000000..8b2fc40e92d0
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_internal.h
@@ -0,0 +1,44 @@
+/*
+ * 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>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef REMOTEPROC_INTERNAL_H
+#define REMOTEPROC_INTERNAL_H
+
+#include <linux/irqreturn.h>
+
+struct rproc;
+
+/* from remoteproc_core.c */
+void rproc_release(struct kref *kref);
+irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id);
+
+/* from remoteproc_rpmsg.c */
+int rproc_add_rpmsg_vdev(struct rproc *);
+void rproc_remove_rpmsg_vdev(struct rproc *rproc);
+
+/* from remoteproc_debugfs.c */
+void rproc_remove_trace_file(struct dentry *tfile);
+struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
+                                        struct rproc_mem_entry *trace);
+void rproc_delete_debug_dir(struct rproc *rproc);
+void rproc_create_debug_dir(struct rproc *rproc);
+void rproc_init_debugfs(void);
+void rproc_exit_debugfs(void);
+
+#endif /* REMOTEPROC_INTERNAL_H */