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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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-map-ops.h>
 #include <linux/dma-mapping.h>
 #include <linux/dma-direct.h> /* XXX: pokes into bus_dma_range */
 #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 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;
 }
 
 static 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;
     }
 }
 
 static int rproc_vdev_do_start(struct rproc_subdev *subdev)
 {
     struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
 
     return rproc_add_virtio_dev(rvdev, rvdev->id);
 }
 
 static void rproc_vdev_do_stop(struct rproc_subdev *subdev, bool crashed)
 {
     struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
     int ret;
 
     ret = device_for_each_child(&rvdev->dev, NULL, rproc_remove_virtio_dev);
     if (ret)
         dev_warn(&rvdev->dev, "can't remove vdev child device: %d\n", ret);
 }
 
 /**
  * rproc_rvdev_release() - release the existence of a rvdev
  *
  * @dev: the subdevice's dev
  */
 static void rproc_rvdev_release(struct device *dev)
 {
     struct rproc_vdev *rvdev = container_of(dev, struct rproc_vdev, dev);
 
     of_reserved_mem_device_release(dev);
     dma_release_coherent_memory(dev);
 
     kfree(rvdev);
 }
 
 static int copy_dma_range_map(struct device *to, struct device *from)
 {
     const struct bus_dma_region *map = from->dma_range_map, *new_map, *r;
     int num_ranges = 0;
 
     if (!map)
         return 0;
 
     for (r = map; r->size; r++)
         num_ranges++;
 
     new_map = kmemdup(map, array_size(num_ranges + 1, sizeof(*map)),
               GFP_KERNEL);
     if (!new_map)
         return -ENOMEM;
     to->dma_range_map = new_map;
     return 0;
 }
 
 /**
  * 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;
     int i, ret;
     char name[16];
 
     /* make sure resource isn't truncated */
     if (struct_size(rsc, vring, rsc->num_of_vrings) + 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 = kzalloc(sizeof(*rvdev), GFP_KERNEL);
     if (!rvdev)
         return -ENOMEM;
 
     kref_init(&rvdev->refcount);
 
     rvdev->id = rsc->id;
     rvdev->rproc = rproc;
     rvdev->index = rproc->nb_vdev++;
 
     /* Initialise vdev subdevice */
     snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
     rvdev->dev.parent = &rproc->dev;
     rvdev->dev.release = rproc_rvdev_release;
     dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev->dev.parent), name);
     dev_set_drvdata(&rvdev->dev, rvdev);
 
     ret = device_register(&rvdev->dev);
     if (ret) {
         put_device(&rvdev->dev);
         return ret;
     }
 
     ret = copy_dma_range_map(&rvdev->dev, rproc->dev.parent);
     if (ret)
         goto free_rvdev;
 
     /* Make device dma capable by inheriting from parent's capabilities */
     set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
 
     ret = dma_coerce_mask_and_coherent(&rvdev->dev,
                        dma_get_mask(rproc->dev.parent));
     if (ret) {
         dev_warn(dev,
              "Failed to set DMA mask %llx. Trying to continue... (%pe)\n",
              dma_get_mask(rproc->dev.parent), ERR_PTR(ret));
     }
 
     /* parse the vrings */
     for (i = 0; i < rsc->num_of_vrings; i++) {
         ret = rproc_parse_vring(rvdev, rsc, i);
         if (ret)
             goto free_rvdev;
     }
 
     /* remember the resource offset*/
     rvdev->rsc_offset = offset;
 
     /* allocate the vring resources */
     for (i = 0; i < rsc->num_of_vrings; i++) {
         ret = rproc_alloc_vring(rvdev, i);
         if (ret)
             goto unwind_vring_allocations;
     }
 
     list_add_tail(&rvdev->node, &rproc->rvdevs);
 
     rvdev->subdev.start = rproc_vdev_do_start;
     rvdev->subdev.stop = rproc_vdev_do_stop;
 
     rproc_add_subdev(rproc, &rvdev->subdev);
 
     return 0;
 
 unwind_vring_allocations:
     for (i--; i >= 0; i--)
         rproc_free_vring(&rvdev->vring[i]);
 free_rvdev:
     device_unregister(&rvdev->dev);
     return ret;
 }
 
 void rproc_vdev_release(struct kref *ref)
 {
     struct rproc_vdev *rvdev = container_of(ref, struct rproc_vdev, refcount);
     struct rproc_vring *rvring;
     struct rproc *rproc = rvdev->rproc;
     int id;
 
     for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
         rvring = &rvdev->vring[id];
         rproc_free_vring(rvring);
     }
 
     rproc_remove_subdev(rproc, &rvdev->subdev);
     list_del(&rvdev->node);
     device_unregister(&rvdev->dev);
 }
 
 /**
  * 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);
     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);
         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)
         kref_put(&rvdev->refcount, rproc_vdev_release);
 
     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;
 }
 
 /**
  * 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)
 {
     const struct firmware *firmware_p;
     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);
 
     ret = rproc_stop(rproc, true);
     if (ret)
         goto unlock_mutex;
 
     /* 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);
         goto unlock_mutex;
     }
 
     /* boot the remote processor up again */
     ret = rproc_start(rproc, firmware_p);
 
     release_firmware(firmware_p);
 
 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 || rproc->state == RPROC_OFFLINE) {
         /* handle only the first crash detected */
         mutex_unlock(&rproc->lock);
         return;
     }
 
     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);
 
     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 && r->dev.parent->of_node == 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_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Generic Remote Processor Framework");

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