diff options
Diffstat (limited to 'drivers/remoteproc/remoteproc_core.c')
| -rw-r--r-- | drivers/remoteproc/remoteproc_core.c | 1419 |
1 files changed, 1419 insertions, 0 deletions
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c new file mode 100644 index 000000000..17086455b --- /dev/null +++ b/drivers/remoteproc/remoteproc_core.c @@ -0,0 +1,1419 @@ +/* + * 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/idr.h> +#include <linux/elf.h> +#include <linux/crc32.h> +#include <linux/virtio_ids.h> +#include <linux/virtio_ring.h> +#include <asm/byteorder.h> + +#include "remoteproc_internal.h" + +typedef int (*rproc_handle_resources_t)(struct rproc *rproc, + struct resource_table *table, int len); +typedef int (*rproc_handle_resource_t)(struct rproc *rproc, + void *, int offset, int avail); + +/* Unique indices for remoteproc devices */ +static DEFINE_IDA(rproc_dev_index); + +static const char * const rproc_crash_names[] = { + [RPROC_MMUFAULT] = "mmufault", +}; + +/* 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); + + 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. + */ +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; +} +EXPORT_SYMBOL(rproc_da_to_va); + +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; + dma_addr_t dma; + void *va; + int ret, size, notifyid; + + /* actual size of vring (in bytes) */ + size = PAGE_ALIGN(vring_size(rvring->len, rvring->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->parent, size, &dma, GFP_KERNEL); + if (!va) { + dev_err(dev->parent, "dma_alloc_coherent failed\n"); + return -EINVAL; + } + + /* + * 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); + dma_free_coherent(dev->parent, size, va, dma); + return ret; + } + notifyid = ret; + + dev_dbg(dev, "vring%d: va %p dma %llx size %x idr %d\n", i, va, + (unsigned long long)dma, size, notifyid); + + rvring->va = va; + rvring->dma = dma; + rvring->notifyid = notifyid; + + /* + * Let the rproc know the notifyid and da of this vring. + * Not all platforms use dma_alloc_coherent to automatically + * set up the iommu. In this case the device address (da) will + * hold the physical address and not the device address. + */ + rsc = (void *)rproc->table_ptr + rvdev->rsc_offset; + rsc->vring[i].da = dma; + 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 %x, qsz %d, align %d\n", + i, vring->da, vring->num, vring->align); + + /* make sure reserved bytes are zeroes */ + if (vring->reserved) { + dev_err(dev, "vring rsc has non zero reserved bytes\n"); + return -EINVAL; + } + + /* 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->len = vring->num; + rvring->align = vring->align; + rvring->rvdev = rvdev; + + return 0; +} + +void rproc_free_vring(struct rproc_vring *rvring) +{ + int size = PAGE_ALIGN(vring_size(rvring->len, rvring->align)); + struct rproc *rproc = rvring->rvdev->rproc; + int idx = rvring->rvdev->vring - rvring; + struct fw_rsc_vdev *rsc; + + dma_free_coherent(rproc->dev.parent, size, rvring->va, rvring->dma); + idr_remove(&rproc->notifyids, rvring->notifyid); + + /* reset resource entry info */ + rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset; + rsc->vring[idx].da = 0; + rsc->vring[idx].notifyid = -1; +} + +/** + * rproc_handle_vdev() - handle a vdev fw resource + * @rproc: the remote processor + * @rsc: the vring resource descriptor + * @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!). + * + * Returns 0 on success, or an appropriate error code otherwise + */ +static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, + int offset, int avail) +{ + struct device *dev = &rproc->dev; + struct rproc_vdev *rvdev; + int i, ret; + + /* make sure resource isn't truncated */ + if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct fw_rsc_vdev_vring) + + 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 %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(struct rproc_vdev), GFP_KERNEL); + if (!rvdev) + return -ENOMEM; + + rvdev->rproc = rproc; + + /* 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; + + list_add_tail(&rvdev->node, &rproc->rvdevs); + + /* it is now safe to add the virtio device */ + ret = rproc_add_virtio_dev(rvdev, rsc->id); + if (ret) + goto remove_rvdev; + + return 0; + +remove_rvdev: + list_del(&rvdev->node); +free_rvdev: + kfree(rvdev); + return ret; +} + +/** + * rproc_handle_trace() - handle a shared trace buffer resource + * @rproc: the remote processor + * @rsc: the trace resource descriptor + * @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). + * + * Returns 0 on success, or an appropriate error code otherwise + */ +static int rproc_handle_trace(struct rproc *rproc, struct fw_rsc_trace *rsc, + int offset, int avail) +{ + struct rproc_mem_entry *trace; + struct device *dev = &rproc->dev; + void *ptr; + 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; + } + + /* 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%x, 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 + * @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. + */ +static int rproc_handle_devmem(struct rproc *rproc, struct fw_rsc_devmem *rsc, + int offset, int avail) +{ + 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) { + dev_err(dev, "kzalloc mapping failed\n"); + 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_handle_carveout() - handle phys contig memory allocation requests + * @rproc: rproc handle + * @rsc: 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. + */ +static int rproc_handle_carveout(struct rproc *rproc, + struct fw_rsc_carveout *rsc, + int offset, int avail) + +{ + struct rproc_mem_entry *carveout, *mapping; + struct device *dev = &rproc->dev; + dma_addr_t dma; + void *va; + int ret; + + 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: da %x, pa %x, len %x, flags %x\n", + rsc->da, rsc->pa, rsc->len, rsc->flags); + + carveout = kzalloc(sizeof(*carveout), GFP_KERNEL); + if (!carveout) { + dev_err(dev, "kzalloc carveout failed\n"); + return -ENOMEM; + } + + va = dma_alloc_coherent(dev->parent, rsc->len, &dma, GFP_KERNEL); + if (!va) { + dev_err(dev->parent, "dma_alloc_coherent err: %d\n", rsc->len); + ret = -ENOMEM; + goto free_carv; + } + + dev_dbg(dev, "carveout va %p, dma %llx, len 0x%x\n", va, + (unsigned long long)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) { + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); + if (!mapping) { + dev_err(dev, "kzalloc mapping failed\n"); + ret = -ENOMEM; + goto dma_free; + } + + ret = iommu_map(rproc->domain, rsc->da, dma, rsc->len, + rsc->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 = rsc->da; + mapping->len = rsc->len; + list_add_tail(&mapping->node, &rproc->mappings); + + dev_dbg(dev, "carveout mapped 0x%x to 0x%llx\n", + rsc->da, (unsigned long long)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). + * + * Non-IOMMU processors might also want to have this info. + * In this case, the device address and the physical address + * are the same. + */ + 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; + +free_mapping: + kfree(mapping); +dma_free: + dma_free_coherent(dev->parent, rsc->len, va, dma); +free_carv: + kfree(carveout); + return ret; +} + +static int rproc_count_vrings(struct rproc *rproc, struct fw_rsc_vdev *rsc, + int offset, int avail) +{ + /* Summarize the number of notification IDs */ + rproc->max_notifyid += rsc->num_of_vrings; + + return 0; +} + +/* + * 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_resource_t)rproc_handle_carveout, + [RSC_DEVMEM] = (rproc_handle_resource_t)rproc_handle_devmem, + [RSC_TRACE] = (rproc_handle_resource_t)rproc_handle_trace, + [RSC_VDEV] = NULL, /* VDEVs were handled upon registrarion */ +}; + +static rproc_handle_resource_t rproc_vdev_handler[RSC_LAST] = { + [RSC_VDEV] = (rproc_handle_resource_t)rproc_handle_vdev, +}; + +static rproc_handle_resource_t rproc_count_vrings_handler[RSC_LAST] = { + [RSC_VDEV] = (rproc_handle_resource_t)rproc_count_vrings, +}; + +/* handle firmware resource entries before booting the remote processor */ +static int rproc_handle_resources(struct rproc *rproc, int len, + rproc_handle_resource_t handlers[RSC_LAST]) +{ + struct device *dev = &rproc->dev; + rproc_handle_resource_t handler; + int ret = 0, i; + + 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 = len - 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_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; +} + +/** + * 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. + */ +static void rproc_resource_cleanup(struct rproc *rproc) +{ + struct rproc_mem_entry *entry, *tmp; + struct device *dev = &rproc->dev; + + /* 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); + } + + /* 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/%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) { + dma_free_coherent(dev->parent, entry->len, entry->va, entry->dma); + list_del(&entry->node); + kfree(entry); + } +} + +/* + * 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 resource_table *table, *loaded_table; + int ret, tablesz; + + if (!rproc->table_ptr) + return -ENOMEM; + + 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; + } + + rproc->bootaddr = rproc_get_boot_addr(rproc, fw); + ret = -EINVAL; + + /* look for the resource table */ + table = rproc_find_rsc_table(rproc, fw, &tablesz); + if (!table) { + goto clean_up; + } + + /* Verify that resource table in loaded fw is unchanged */ + if (rproc->table_csum != crc32(0, table, tablesz)) { + dev_err(dev, "resource checksum failed, fw changed?\n"); + goto clean_up; + } + + /* handle fw resources which are required to boot rproc */ + ret = rproc_handle_resources(rproc, tablesz, rproc_loading_handlers); + 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); + if (ret) { + dev_err(dev, "Failed to load program segments: %d\n", ret); + goto clean_up; + } + + /* + * 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. + */ + loaded_table = rproc_find_loaded_rsc_table(rproc, fw); + if (!loaded_table) { + ret = -EINVAL; + goto clean_up; + } + + memcpy(loaded_table, rproc->cached_table, tablesz); + + /* 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; + } + + /* + * Update table_ptr so that all subsequent vring allocations and + * virtio fields manipulation update the actual loaded resource table + * in device memory. + */ + rproc->table_ptr = loaded_table; + + 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 resource_table *table; + int ret, tablesz; + + if (rproc_fw_sanity_check(rproc, fw) < 0) + goto out; + + /* look for the resource table */ + table = rproc_find_rsc_table(rproc, fw, &tablesz); + if (!table) + goto out; + + rproc->table_csum = crc32(0, table, tablesz); + + /* + * Create a copy of the resource table. When a virtio device starts + * and calls vring_new_virtqueue() the address of the allocated vring + * will be stored in the cached_table. Before the device is started, + * cached_table will be copied into devic memory. + */ + rproc->cached_table = kmemdup(table, tablesz, GFP_KERNEL); + if (!rproc->cached_table) + goto out; + + rproc->table_ptr = rproc->cached_table; + + /* count the number of notify-ids */ + rproc->max_notifyid = -1; + ret = rproc_handle_resources(rproc, tablesz, rproc_count_vrings_handler); + if (ret) + goto out; + + /* look for virtio devices and register them */ + ret = rproc_handle_resources(rproc, tablesz, rproc_vdev_handler); + +out: + release_firmware(fw); + /* allow rproc_del() contexts, if any, to proceed */ + complete_all(&rproc->firmware_loading_complete); +} + +static int rproc_add_virtio_devices(struct rproc *rproc) +{ + int ret; + + /* rproc_del() 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 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 = maybe_reject_firmware_nowait(THIS_MODULE, FW_ACTION_HOTPLUG, + rproc->firmware, &rproc->dev, GFP_KERNEL, + rproc, rproc_fw_config_virtio); + if (ret < 0) { + dev_err(&rproc->dev, "request_firmware_nowait err: %d\n", ret); + complete_all(&rproc->firmware_loading_complete); + } + + return ret; +} + +/** + * rproc_trigger_recovery() - recover a remoteproc + * @rproc: the remote processor + * + * The recovery is done by reseting 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. + */ +int rproc_trigger_recovery(struct rproc *rproc) +{ + struct rproc_vdev *rvdev, *rvtmp; + + dev_err(&rproc->dev, "recovering %s\n", rproc->name); + + init_completion(&rproc->crash_comp); + + /* clean up remote vdev entries */ + list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node) + rproc_remove_virtio_dev(rvdev); + + /* wait until there is no more rproc users */ + wait_for_completion(&rproc->crash_comp); + + /* Free the copy of the resource table */ + kfree(rproc->cached_table); + + return rproc_add_virtio_devices(rproc); +} + +/** + * rproc_crash_handler_work() - handle a 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); +} + +/** + * 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->parent->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 = maybe_reject_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->parent->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. + */ +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); + + /* Give the next start a clean resource table */ + rproc->table_ptr = rproc->cached_table; + + /* if in crash state, unlock crash handler */ + if (rproc->state == RPROC_CRASHED) + complete_all(&rproc->crash_comp); + + rproc->state = RPROC_OFFLINE; + + dev_info(dev, "stopped remote processor %s\n", rproc->name); + +out: + mutex_unlock(&rproc->lock); + if (!ret) + module_put(dev->parent->driver->owner); +} +EXPORT_SYMBOL(rproc_shutdown); + +/** + * 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. + * + * 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 might be + * probed. + */ +int rproc_add(struct rproc *rproc) +{ + struct device *dev = &rproc->dev; + int ret; + + ret = device_add(dev); + if (ret < 0) + return ret; + + dev_info(dev, "%s is available\n", rproc->name); + + dev_info(dev, "Note: remoteproc is still under development and considered experimental.\n"); + dev_info(dev, "THE BINARY FORMAT IS NOT YET FINALIZED, and backward compatibility isn't yet guaranteed.\n"); + + /* create debugfs entries */ + rproc_create_debug_dir(rproc); + + return rproc_add_virtio_devices(rproc); +} +EXPORT_SYMBOL(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); + + rproc_delete_debug_dir(rproc); + + idr_destroy(&rproc->notifyids); + + if (rproc->index >= 0) + ida_simple_remove(&rproc_dev_index, rproc->index); + + kfree(rproc); +} + +static struct device_type rproc_type = { + .name = "remoteproc", + .release = rproc_type_release, +}; + +/** + * 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. + * + * On success the new rproc is returned, and on failure, NULL. + * + * Note: _never_ directly deallocate @rproc, even if it was not registered + * yet. Instead, when you need to unroll rproc_alloc(), use rproc_put(). + */ +struct rproc *rproc_alloc(struct device *dev, const char *name, + const struct rproc_ops *ops, + const char *firmware, int len) +{ + struct rproc *rproc; + char *p, *template = "rproc-%s-fw"; + int name_len = 0; + + if (!dev || !name || !ops) + return NULL; + + if (!firmware) + /* + * Make room for default firmware name (minus %s plus '\0'). + * If the caller didn't pass in a firmware name then + * construct a default name. We're already glomming 'len' + * bytes onto the end of the struct rproc allocation, so do + * a few more for the default firmware name (but only if + * the caller doesn't pass one). + */ + name_len = strlen(name) + strlen(template) - 2 + 1; + + rproc = kzalloc(sizeof(struct rproc) + len + name_len, GFP_KERNEL); + if (!rproc) { + dev_err(dev, "%s: kzalloc failed\n", __func__); + return NULL; + } + + if (!firmware) { + p = (char *)rproc + sizeof(struct rproc) + len; + snprintf(p, name_len, template, name); + } else { + p = (char *)firmware; + } + + rproc->firmware = p; + rproc->name = name; + rproc->ops = ops; + rproc->priv = &rproc[1]; + + device_initialize(&rproc->dev); + rproc->dev.parent = dev; + rproc->dev.type = &rproc_type; + + /* Assign a unique device index and name */ + rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL); + if (rproc->index < 0) { + dev_err(dev, "ida_simple_get failed: %d\n", rproc->index); + put_device(&rproc->dev); + return NULL; + } + + dev_set_name(&rproc->dev, "remoteproc%d", rproc->index); + + atomic_set(&rproc->power, 0); + + /* Set ELF as the default fw_ops handler */ + rproc->fw_ops = &rproc_elf_fw_ops; + + mutex_init(&rproc->lock); + + idr_init(&rproc->notifyids); + + INIT_LIST_HEAD(&rproc->carveouts); + INIT_LIST_HEAD(&rproc->mappings); + INIT_LIST_HEAD(&rproc->traces); + INIT_LIST_HEAD(&rproc->rvdevs); + + INIT_WORK(&rproc->crash_handler, rproc_crash_handler_work); + init_completion(&rproc->crash_comp); + + rproc->state = RPROC_OFFLINE; + + return rproc; +} +EXPORT_SYMBOL(rproc_alloc); + +/** + * rproc_put() - 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_put(struct rproc *rproc) +{ + 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_put(). + * + * Returns 0 on success and -EINVAL if @rproc isn't valid. + */ +int rproc_del(struct rproc *rproc) +{ + struct rproc_vdev *rvdev, *tmp; + + if (!rproc) + return -EINVAL; + + /* if rproc is just being registered, wait */ + wait_for_completion(&rproc->firmware_loading_complete); + + /* clean up remote vdev entries */ + list_for_each_entry_safe(rvdev, tmp, &rproc->rvdevs, node) + rproc_remove_virtio_dev(rvdev); + + /* Free the copy of the resource table */ + kfree(rproc->cached_table); + + device_del(&rproc->dev); + + return 0; +} +EXPORT_SYMBOL(rproc_del); + +/** + * 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; + } + + dev_err(&rproc->dev, "crash detected in %s: type %s\n", + rproc->name, rproc_crash_to_string(type)); + + /* create a new task to handle the error */ + schedule_work(&rproc->crash_handler); +} +EXPORT_SYMBOL(rproc_report_crash); + +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"); |