| /* |
| * Remote Processor Framework |
| * |
| * Copyright (C) 2011 Texas Instruments, Inc. |
| * Copyright (C) 2011 Google, Inc. |
| * |
| * Ohad Ben-Cohen <ohad@wizery.com> |
| * Brian Swetland <swetland@google.com> |
| * Mark Grosen <mgrosen@ti.com> |
| * Fernando Guzman Lugo <fernando.lugo@ti.com> |
| * Suman Anna <s-anna@ti.com> |
| * Robert Tivy <rtivy@ti.com> |
| * Armando Uribe De Leon <x0095078@ti.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #define pr_fmt(fmt) "%s: " fmt, __func__ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/device.h> |
| #include <linux/slab.h> |
| #include <linux/mutex.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/firmware.h> |
| #include <linux/string.h> |
| #include <linux/debugfs.h> |
| #include <linux/remoteproc.h> |
| #include <linux/iommu.h> |
| #include <linux/klist.h> |
| #include <linux/elf.h> |
| #include <linux/virtio_ids.h> |
| #include <linux/virtio_ring.h> |
| |
| #include "remoteproc_internal.h" |
| |
| static void klist_rproc_get(struct klist_node *n); |
| static void klist_rproc_put(struct klist_node *n); |
| |
| /* |
| * klist of the available remote processors. |
| * |
| * We need this in order to support name-based lookups (needed by the |
| * rproc_get_by_name()). |
| * |
| * That said, we don't use rproc_get_by_name() anymore within the rpmsg |
| * framework. The use cases that do require its existence should be |
| * scrutinized, and hopefully migrated to rproc_boot() using device-based |
| * binding. |
| * |
| * If/when this materializes, we could drop the klist (and the by_name |
| * API). |
| */ |
| static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put); |
| |
| typedef int (*rproc_handle_resources_t)(struct rproc *rproc, |
| struct fw_resource *rsc, int len); |
| |
| /* |
| * This is the IOMMU fault handler we register with the IOMMU API |
| * (when relevant; not all remote processors access memory through |
| * an IOMMU). |
| * |
| * IOMMU core will invoke this handler whenever the remote processor |
| * will try to access an unmapped device address. |
| * |
| * Currently this is mostly a stub, but it will be later used to trigger |
| * the recovery of the remote processor. |
| */ |
| static int rproc_iommu_fault(struct iommu_domain *domain, struct device *dev, |
| unsigned long iova, int flags) |
| { |
| dev_err(dev, "iommu fault: da 0x%lx flags 0x%x\n", iova, flags); |
| |
| /* |
| * Let the iommu core know we're not really handling this fault; |
| * we just plan to use this as a recovery trigger. |
| */ |
| return -ENOSYS; |
| } |
| |
| static int rproc_enable_iommu(struct rproc *rproc) |
| { |
| struct iommu_domain *domain; |
| struct device *dev = rproc->dev; |
| int ret; |
| |
| /* |
| * We currently use iommu_present() to decide if an IOMMU |
| * setup is needed. |
| * |
| * This works for simple cases, but will easily fail with |
| * platforms that do have an IOMMU, but not for this specific |
| * rproc. |
| * |
| * This will be easily solved by introducing hw capabilities |
| * that will be set by the remoteproc driver. |
| */ |
| if (!iommu_present(dev->bus)) { |
| dev_dbg(dev, "iommu not found\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); |
| |
| ret = iommu_attach_device(domain, dev); |
| if (ret) { |
| dev_err(dev, "can't attach iommu device: %d\n", ret); |
| goto free_domain; |
| } |
| |
| rproc->domain = domain; |
| |
| return 0; |
| |
| free_domain: |
| iommu_domain_free(domain); |
| return ret; |
| } |
| |
| static void rproc_disable_iommu(struct rproc *rproc) |
| { |
| struct iommu_domain *domain = rproc->domain; |
| struct device *dev = rproc->dev; |
| |
| if (!domain) |
| return; |
| |
| iommu_detach_device(domain, dev); |
| iommu_domain_free(domain); |
| |
| return; |
| } |
| |
| /* |
| * Some remote processors will ask us to allocate them physically contiguous |
| * memory regions (which we call "carveouts"), and map them to specific |
| * device addresses (which are hardcoded in the firmware). |
| * |
| * They may then ask us to copy objects into specific device addresses (e.g. |
| * code/data sections) or expose us certain symbols in other device address |
| * (e.g. their trace buffer). |
| * |
| * This function is an internal helper with which we can go over the allocated |
| * carveouts and translate specific device address to kernel virtual addresses |
| * so we can access the referenced memory. |
| * |
| * Note: phys_to_virt(iommu_iova_to_phys(rproc->domain, da)) will work too, |
| * but only on kernel direct mapped RAM memory. Instead, we're just using |
| * here the output of the DMA API, which should be more correct. |
| */ |
| static void *rproc_da_to_va(struct rproc *rproc, u64 da, int len) |
| { |
| struct rproc_mem_entry *carveout; |
| void *ptr = NULL; |
| |
| list_for_each_entry(carveout, &rproc->carveouts, node) { |
| int offset = da - carveout->da; |
| |
| /* try next carveout if da is too small */ |
| if (offset < 0) |
| continue; |
| |
| /* try next carveout if da is too large */ |
| if (offset + len > carveout->len) |
| continue; |
| |
| ptr = carveout->va + offset; |
| |
| break; |
| } |
| |
| return ptr; |
| } |
| |
| /** |
| * rproc_load_segments() - load firmware segments to memory |
| * @rproc: remote processor which will be booted using these fw segments |
| * @elf_data: the content of the ELF firmware image |
| * @len: firmware size (in bytes) |
| * |
| * This function loads the firmware segments to memory, where the remote |
| * processor expects them. |
| * |
| * Some remote processors will expect their code and data to be placed |
| * in specific device addresses, and can't have them dynamically assigned. |
| * |
| * We currently support only those kind of remote processors, and expect |
| * the program header's paddr member to contain those addresses. We then go |
| * through the physically contiguous "carveout" memory regions which we |
| * allocated (and mapped) earlier on behalf of the remote processor, |
| * and "translate" device address to kernel addresses, so we can copy the |
| * segments where they are expected. |
| * |
| * Currently we only support remote processors that required carveout |
| * allocations and got them mapped onto their iommus. Some processors |
| * might be different: they might not have iommus, and would prefer to |
| * directly allocate memory for every segment/resource. This is not yet |
| * supported, though. |
| */ |
| static int |
| rproc_load_segments(struct rproc *rproc, const u8 *elf_data, size_t len) |
| { |
| struct device *dev = rproc->dev; |
| struct elf32_hdr *ehdr; |
| struct elf32_phdr *phdr; |
| int i, ret = 0; |
| |
| ehdr = (struct elf32_hdr *)elf_data; |
| phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff); |
| |
| /* go through the available ELF segments */ |
| for (i = 0; i < ehdr->e_phnum; i++, phdr++) { |
| u32 da = phdr->p_paddr; |
| u32 memsz = phdr->p_memsz; |
| u32 filesz = phdr->p_filesz; |
| u32 offset = phdr->p_offset; |
| void *ptr; |
| |
| if (phdr->p_type != PT_LOAD) |
| continue; |
| |
| dev_dbg(dev, "phdr: type %d da 0x%x memsz 0x%x filesz 0x%x\n", |
| phdr->p_type, da, memsz, filesz); |
| |
| if (filesz > memsz) { |
| dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n", |
| filesz, memsz); |
| ret = -EINVAL; |
| break; |
| } |
| |
| if (offset + filesz > len) { |
| dev_err(dev, "truncated fw: need 0x%x avail 0x%x\n", |
| offset + filesz, len); |
| ret = -EINVAL; |
| break; |
| } |
| |
| /* grab the kernel address for this device address */ |
| ptr = rproc_da_to_va(rproc, da, memsz); |
| if (!ptr) { |
| dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz); |
| ret = -EINVAL; |
| break; |
| } |
| |
| /* put the segment where the remote processor expects it */ |
| if (phdr->p_filesz) |
| memcpy(ptr, elf_data + phdr->p_offset, filesz); |
| |
| /* |
| * Zero out remaining memory for this segment. |
| * |
| * This isn't strictly required since dma_alloc_coherent already |
| * did this for us. albeit harmless, we may consider removing |
| * this. |
| */ |
| if (memsz > filesz) |
| memset(ptr + filesz, 0, memsz - filesz); |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * rproc_handle_virtio_hdr() - handle a virtio header resource |
| * @rproc: the remote processor |
| * @rsc: the resource descriptor |
| * |
| * The existence of this virtio hdr resource entry means that the firmware |
| * of this @rproc supports this virtio device. |
| * |
| * Currently we support only a single virtio device of type VIRTIO_ID_RPMSG, |
| * but the plan is to remove this limitation and support any number |
| * of virtio devices (and of any type). We'll also add support for dynamically |
| * adding (and removing) virtio devices over the rpmsg bus, but small |
| * firmwares that doesn't want to get involved with rpmsg will be able |
| * to simple use the resource table for this. |
| * |
| * At this point this virtio header entry is rather simple: it just |
| * announces the virtio device id and the supported virtio device features. |
| * The plan though is to extend this to include the vring information and |
| * the virtio config space, too (but first, some resource table overhaul |
| * is needed: move from fixed-sized to variable-length TLV entries). |
| * |
| * For now, the 'flags' member of the resource entry contains the virtio |
| * device id, the 'da' member contains the device features, and 'pa' is |
| * where we need to store the guest features once negotiation completes. |
| * As usual, the 'id' member of this resource contains the index of this |
| * resource type (i.e. is this the first virtio hdr entry, the 2nd, ...). |
| * |
| * Returns 0 on success, or an appropriate error code otherwise |
| */ |
| static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc) |
| { |
| struct rproc_vdev *rvdev; |
| |
| /* we only support VIRTIO_ID_RPMSG devices for now */ |
| if (rsc->flags != VIRTIO_ID_RPMSG) { |
| dev_warn(rproc->dev, "unsupported vdev: %d\n", rsc->flags); |
| return -EINVAL; |
| } |
| |
| /* we only support a single vdev per rproc for now */ |
| if (rsc->id || rproc->rvdev) { |
| dev_warn(rproc->dev, "redundant vdev entry: %s\n", rsc->name); |
| return -EINVAL; |
| } |
| |
| rvdev = kzalloc(sizeof(struct rproc_vdev), GFP_KERNEL); |
| if (!rvdev) |
| return -ENOMEM; |
| |
| /* remember the device features */ |
| rvdev->dfeatures = rsc->da; |
| |
| rproc->rvdev = rvdev; |
| rvdev->rproc = rproc; |
| |
| return 0; |
| } |
| |
| /** |
| * rproc_handle_vring() - handle a vring fw resource |
| * @rproc: the remote processor |
| * @rsc: the vring resource descriptor |
| * |
| * This resource entry requires allocation of non-cacheable memory |
| * for a virtio vring. Currently we only support two vrings per remote |
| * processor, required for the virtio rpmsg device. |
| * |
| * The 'len' member of @rsc should contain the number of buffers this vring |
| * support and 'da' should either contain the device address where |
| * the remote processor is expecting the vring, or indicate that |
| * dynamically allocation of the vring's device address is supported. |
| * |
| * Note: 'da' is currently not handled. This will be revised when the generic |
| * iommu-based DMA API will arrive, or a dynanic & non-iommu use case show |
| * up. Meanwhile, statically-addressed iommu-based images should use |
| * RSC_DEVMEM resource entries to map their require 'da' to the physical |
| * address of their base CMA region. |
| * |
| * Returns 0 on success, or an appropriate error code otherwise |
| */ |
| static int rproc_handle_vring(struct rproc *rproc, struct fw_resource *rsc) |
| { |
| struct device *dev = rproc->dev; |
| struct rproc_vdev *rvdev = rproc->rvdev; |
| dma_addr_t dma; |
| int size, id = rsc->id; |
| void *va; |
| |
| /* no vdev is in place ? */ |
| if (!rvdev) { |
| dev_err(dev, "vring requested without a virtio dev entry\n"); |
| return -EINVAL; |
| } |
| |
| /* the firmware must provide the expected queue size */ |
| if (!rsc->len) { |
| dev_err(dev, "missing expected queue size\n"); |
| return -EINVAL; |
| } |
| |
| /* we currently support two vrings per rproc (for rx and tx) */ |
| if (id >= ARRAY_SIZE(rvdev->vring)) { |
| dev_err(dev, "%s: invalid vring id %d\n", rsc->name, id); |
| return -EINVAL; |
| } |
| |
| /* have we already allocated this vring id ? */ |
| if (rvdev->vring[id].len) { |
| dev_err(dev, "%s: duplicated id %d\n", rsc->name, id); |
| return -EINVAL; |
| } |
| |
| /* actual size of vring (in bytes) */ |
| size = PAGE_ALIGN(vring_size(rsc->len, AMP_VRING_ALIGN)); |
| |
| /* |
| * Allocate non-cacheable memory for the vring. In the future |
| * this call will also configure the IOMMU for us |
| */ |
| va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL); |
| if (!va) { |
| dev_err(dev, "dma_alloc_coherent failed\n"); |
| return -ENOMEM; |
| } |
| |
| dev_dbg(dev, "vring%d: va %p dma %x qsz %d ring size %x\n", id, va, |
| dma, rsc->len, size); |
| |
| rvdev->vring[id].len = rsc->len; |
| rvdev->vring[id].va = va; |
| rvdev->vring[id].dma = dma; |
| |
| return 0; |
| } |
| |
| /** |
| * rproc_handle_trace() - handle a shared trace buffer resource |
| * @rproc: the remote processor |
| * @rsc: the trace resource descriptor |
| * |
| * In case the remote processor dumps trace logs into memory, |
| * export it via debugfs. |
| * |
| * Currently, the 'da' member of @rsc should contain the device address |
| * where the remote processor is dumping the traces. Later we could also |
| * support dynamically allocating this address using the generic |
| * DMA API (but currently there isn't a use case for that). |
| * |
| * Returns 0 on success, or an appropriate error code otherwise |
| */ |
| static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc) |
| { |
| struct rproc_mem_entry *trace; |
| struct device *dev = rproc->dev; |
| void *ptr; |
| char name[15]; |
| |
| /* what's the kernel address of this resource ? */ |
| ptr = rproc_da_to_va(rproc, rsc->da, rsc->len); |
| if (!ptr) { |
| dev_err(dev, "erroneous trace resource entry\n"); |
| return -EINVAL; |
| } |
| |
| trace = kzalloc(sizeof(*trace), GFP_KERNEL); |
| if (!trace) { |
| dev_err(dev, "kzalloc trace failed\n"); |
| return -ENOMEM; |
| } |
| |
| /* set the trace buffer dma properties */ |
| trace->len = rsc->len; |
| trace->va = ptr; |
| |
| /* make sure snprintf always null terminates, even if truncating */ |
| snprintf(name, sizeof(name), "trace%d", rproc->num_traces); |
| |
| /* create the debugfs entry */ |
| trace->priv = rproc_create_trace_file(name, rproc, trace); |
| if (!trace->priv) { |
| trace->va = NULL; |
| kfree(trace); |
| return -EINVAL; |
| } |
| |
| list_add_tail(&trace->node, &rproc->traces); |
| |
| rproc->num_traces++; |
| |
| dev_dbg(dev, "%s added: va %p, da 0x%llx, len 0x%x\n", name, ptr, |
| rsc->da, rsc->len); |
| |
| return 0; |
| } |
| |
| /** |
| * rproc_handle_devmem() - handle devmem resource entry |
| * @rproc: remote processor handle |
| * @rsc: the devmem resource entry |
| * |
| * Remote processors commonly need to access certain on-chip peripherals. |
| * |
| * Some of these remote processors access memory via an iommu device, |
| * and might require us to configure their iommu before they can access |
| * the on-chip peripherals they need. |
| * |
| * This resource entry is a request to map such a peripheral device. |
| * |
| * These devmem entries will contain the physical address of the device in |
| * the 'pa' member. If a specific device address is expected, then 'da' will |
| * contain it (currently this is the only use case supported). 'len' will |
| * contain the size of the physical region we need to map. |
| * |
| * Currently we just "trust" those devmem entries to contain valid physical |
| * addresses, but this is going to change: we want the implementations to |
| * tell us ranges of physical addresses the firmware is allowed to request, |
| * and not allow firmwares to request access to physical addresses that |
| * are outside those ranges. |
| */ |
| static int rproc_handle_devmem(struct rproc *rproc, struct fw_resource *rsc) |
| { |
| struct rproc_mem_entry *mapping; |
| int ret; |
| |
| /* no point in handling this resource without a valid iommu domain */ |
| if (!rproc->domain) |
| return -EINVAL; |
| |
| mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); |
| if (!mapping) { |
| dev_err(rproc->dev, "kzalloc mapping failed\n"); |
| return -ENOMEM; |
| } |
| |
| ret = iommu_map(rproc->domain, rsc->da, rsc->pa, rsc->len, rsc->flags); |
| if (ret) { |
| dev_err(rproc->dev, "failed to map devmem: %d\n", ret); |
| goto out; |
| } |
| |
| /* |
| * We'll need this info later when we'll want to unmap everything |
| * (e.g. on shutdown). |
| * |
| * We can't trust the remote processor not to change the resource |
| * table, so we must maintain this info independently. |
| */ |
| mapping->da = rsc->da; |
| mapping->len = rsc->len; |
| list_add_tail(&mapping->node, &rproc->mappings); |
| |
| dev_dbg(rproc->dev, "mapped devmem pa 0x%llx, da 0x%llx, len 0x%x\n", |
| rsc->pa, rsc->da, rsc->len); |
| |
| return 0; |
| |
| out: |
| kfree(mapping); |
| return ret; |
| } |
| |
| /** |
| * rproc_handle_carveout() - handle phys contig memory allocation requests |
| * @rproc: rproc handle |
| * @rsc: the resource entry |
| * |
| * This function will handle firmware requests for allocation of physically |
| * contiguous memory regions. |
| * |
| * These request entries should come first in the firmware's resource table, |
| * as other firmware entries might request placing other data objects inside |
| * these memory regions (e.g. data/code segments, trace resource entries, ...). |
| * |
| * Allocating memory this way helps utilizing the reserved physical memory |
| * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries |
| * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB |
| * pressure is important; it may have a substantial impact on performance. |
| */ |
| static int rproc_handle_carveout(struct rproc *rproc, struct fw_resource *rsc) |
| { |
| struct rproc_mem_entry *carveout, *mapping; |
| struct device *dev = rproc->dev; |
| dma_addr_t dma; |
| void *va; |
| int ret; |
| |
| mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); |
| if (!mapping) { |
| dev_err(dev, "kzalloc mapping failed\n"); |
| return -ENOMEM; |
| } |
| |
| carveout = kzalloc(sizeof(*carveout), GFP_KERNEL); |
| if (!carveout) { |
| dev_err(dev, "kzalloc carveout failed\n"); |
| ret = -ENOMEM; |
| goto free_mapping; |
| } |
| |
| va = dma_alloc_coherent(dev, rsc->len, &dma, GFP_KERNEL); |
| if (!va) { |
| dev_err(dev, "failed to dma alloc carveout: %d\n", rsc->len); |
| ret = -ENOMEM; |
| goto free_carv; |
| } |
| |
| dev_dbg(dev, "carveout va %p, dma %x, len 0x%x\n", va, dma, rsc->len); |
| |
| /* |
| * Ok, this is non-standard. |
| * |
| * Sometimes we can't rely on the generic iommu-based DMA API |
| * to dynamically allocate the device address and then set the IOMMU |
| * tables accordingly, because some remote processors might |
| * _require_ us to use hard coded device addresses that their |
| * firmware was compiled with. |
| * |
| * In this case, we must use the IOMMU API directly and map |
| * the memory to the device address as expected by the remote |
| * processor. |
| * |
| * Obviously such remote processor devices should not be configured |
| * to use the iommu-based DMA API: we expect 'dma' to contain the |
| * physical address in this case. |
| */ |
| if (rproc->domain) { |
| ret = iommu_map(rproc->domain, rsc->da, dma, rsc->len, |
| rsc->flags); |
| if (ret) { |
| dev_err(dev, "iommu_map failed: %d\n", ret); |
| goto dma_free; |
| } |
| |
| /* |
| * We'll need this info later when we'll want to unmap |
| * everything (e.g. on shutdown). |
| * |
| * We can't trust the remote processor not to change the |
| * resource table, so we must maintain this info independently. |
| */ |
| mapping->da = rsc->da; |
| mapping->len = rsc->len; |
| list_add_tail(&mapping->node, &rproc->mappings); |
| |
| dev_dbg(dev, "carveout mapped 0x%llx to 0x%x\n", rsc->da, dma); |
| |
| /* |
| * Some remote processors might need to know the pa |
| * even though they are behind an IOMMU. E.g., OMAP4's |
| * remote M3 processor needs this so it can control |
| * on-chip hardware accelerators that are not behind |
| * the IOMMU, and therefor must know the pa. |
| * |
| * Generally we don't want to expose physical addresses |
| * if we don't have to (remote processors are generally |
| * _not_ trusted), so we might want to do this only for |
| * remote processor that _must_ have this (e.g. OMAP4's |
| * dual M3 subsystem). |
| */ |
| rsc->pa = dma; |
| } |
| |
| carveout->va = va; |
| carveout->len = rsc->len; |
| carveout->dma = dma; |
| carveout->da = rsc->da; |
| |
| list_add_tail(&carveout->node, &rproc->carveouts); |
| |
| return 0; |
| |
| dma_free: |
| dma_free_coherent(dev, rsc->len, va, dma); |
| free_carv: |
| kfree(carveout); |
| free_mapping: |
| kfree(mapping); |
| return ret; |
| } |
| |
| /* handle firmware resource entries before booting the remote processor */ |
| static int |
| rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) |
| { |
| struct device *dev = rproc->dev; |
| int ret = 0; |
| |
| while (len >= sizeof(*rsc)) { |
| dev_dbg(dev, "rsc: type %d, da 0x%llx, pa 0x%llx, len 0x%x, " |
| "id %d, name %s, flags %x\n", rsc->type, rsc->da, |
| rsc->pa, rsc->len, rsc->id, rsc->name, rsc->flags); |
| |
| switch (rsc->type) { |
| case RSC_CARVEOUT: |
| ret = rproc_handle_carveout(rproc, rsc); |
| break; |
| case RSC_DEVMEM: |
| ret = rproc_handle_devmem(rproc, rsc); |
| break; |
| case RSC_TRACE: |
| ret = rproc_handle_trace(rproc, rsc); |
| break; |
| case RSC_VRING: |
| ret = rproc_handle_vring(rproc, rsc); |
| break; |
| case RSC_VIRTIO_DEV: |
| /* this one is handled early upon registration */ |
| break; |
| default: |
| dev_warn(dev, "unsupported resource %d\n", rsc->type); |
| break; |
| } |
| |
| if (ret) |
| break; |
| |
| rsc++; |
| len -= sizeof(*rsc); |
| } |
| |
| return ret; |
| } |
| |
| /* handle firmware resource entries while registering the remote processor */ |
| static int |
| rproc_handle_virtio_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) |
| { |
| struct device *dev = rproc->dev; |
| int ret = -ENODEV; |
| |
| for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc)) |
| if (rsc->type == RSC_VIRTIO_DEV) { |
| dev_dbg(dev, "found vdev %d/%s features %llx\n", |
| rsc->flags, rsc->name, rsc->da); |
| ret = rproc_handle_virtio_hdr(rproc, rsc); |
| break; |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * rproc_handle_resources() - find and handle the resource table |
| * @rproc: the rproc handle |
| * @elf_data: the content of the ELF firmware image |
| * @len: firmware size (in bytes) |
| * @handler: function that should be used to handle the resource table |
| * |
| * This function finds the resource table inside the remote processor's |
| * firmware, and invoke a user-supplied handler with it (we have two |
| * possible handlers: one is invoked upon registration of @rproc, |
| * in order to register the supported virito devices, and the other is |
| * invoked when @rproc is actually booted). |
| * |
| * Currently this function fails if a resource table doesn't exist. |
| * This restriction will be removed when we'll start supporting remote |
| * processors that don't need a resource table. |
| */ |
| static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data, |
| size_t len, rproc_handle_resources_t handler) |
| |
| { |
| struct elf32_hdr *ehdr; |
| struct elf32_shdr *shdr; |
| const char *name_table; |
| int i, ret = -EINVAL; |
| |
| ehdr = (struct elf32_hdr *)elf_data; |
| shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff); |
| name_table = elf_data + shdr[ehdr->e_shstrndx].sh_offset; |
| |
| /* look for the resource table and handle it */ |
| for (i = 0; i < ehdr->e_shnum; i++, shdr++) { |
| if (!strcmp(name_table + shdr->sh_name, ".resource_table")) { |
| struct fw_resource *table = (struct fw_resource *) |
| (elf_data + shdr->sh_offset); |
| |
| if (shdr->sh_offset + shdr->sh_size > len) { |
| dev_err(rproc->dev, |
| "truncated fw: need 0x%x avail 0x%x\n", |
| shdr->sh_offset + shdr->sh_size, len); |
| ret = -EINVAL; |
| } |
| |
| ret = handler(rproc, table, shdr->sh_size); |
| |
| break; |
| } |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * rproc_resource_cleanup() - clean up and free all acquired resources |
| * @rproc: rproc handle |
| * |
| * This function will free all resources acquired for @rproc, and it |
| * is called when @rproc shuts down, or just failed booting. |
| */ |
| static void rproc_resource_cleanup(struct rproc *rproc) |
| { |
| struct rproc_mem_entry *entry, *tmp; |
| struct device *dev = rproc->dev; |
| struct rproc_vdev *rvdev = rproc->rvdev; |
| int i; |
| |
| /* clean up debugfs trace entries */ |
| list_for_each_entry_safe(entry, tmp, &rproc->traces, node) { |
| rproc_remove_trace_file(entry->priv); |
| rproc->num_traces--; |
| list_del(&entry->node); |
| kfree(entry); |
| } |
| |
| /* free the coherent memory allocated for the vrings */ |
| for (i = 0; rvdev && i < ARRAY_SIZE(rvdev->vring); i++) { |
| int qsz = rvdev->vring[i].len; |
| void *va = rvdev->vring[i].va; |
| int dma = rvdev->vring[i].dma; |
| |
| /* virtqueue size is expressed in number of buffers supported */ |
| if (qsz) { |
| /* how many bytes does this vring really occupy ? */ |
| int size = PAGE_ALIGN(vring_size(qsz, AMP_VRING_ALIGN)); |
| |
| dma_free_coherent(rproc->dev, size, va, dma); |
| |
| rvdev->vring[i].len = 0; |
| } |
| } |
| |
| /* clean up carveout allocations */ |
| list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) { |
| dma_free_coherent(dev, entry->len, entry->va, entry->dma); |
| list_del(&entry->node); |
| kfree(entry); |
| } |
| |
| /* clean up iommu mapping entries */ |
| list_for_each_entry_safe(entry, tmp, &rproc->mappings, node) { |
| size_t unmapped; |
| |
| unmapped = iommu_unmap(rproc->domain, entry->da, entry->len); |
| if (unmapped != entry->len) { |
| /* nothing much to do besides complaining */ |
| dev_err(dev, "failed to unmap %u/%u\n", entry->len, |
| unmapped); |
| } |
| |
| list_del(&entry->node); |
| kfree(entry); |
| } |
| } |
| |
| /* make sure this fw image is sane */ |
| static int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw) |
| { |
| const char *name = rproc->firmware; |
| struct device *dev = rproc->dev; |
| struct elf32_hdr *ehdr; |
| |
| if (!fw) { |
| dev_err(dev, "failed to load %s\n", name); |
| return -EINVAL; |
| } |
| |
| if (fw->size < sizeof(struct elf32_hdr)) { |
| dev_err(dev, "Image is too small\n"); |
| return -EINVAL; |
| } |
| |
| ehdr = (struct elf32_hdr *)fw->data; |
| |
| if (fw->size < ehdr->e_shoff + sizeof(struct elf32_shdr)) { |
| dev_err(dev, "Image is too small\n"); |
| return -EINVAL; |
| } |
| |
| if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) { |
| dev_err(dev, "Image is corrupted (bad magic)\n"); |
| return -EINVAL; |
| } |
| |
| if (ehdr->e_phnum == 0) { |
| dev_err(dev, "No loadable segments\n"); |
| return -EINVAL; |
| } |
| |
| if (ehdr->e_phoff > fw->size) { |
| dev_err(dev, "Firmware size is too small\n"); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * take a firmware and boot a remote processor with it. |
| */ |
| static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw) |
| { |
| struct device *dev = rproc->dev; |
| const char *name = rproc->firmware; |
| struct elf32_hdr *ehdr; |
| int ret; |
| |
| ret = rproc_fw_sanity_check(rproc, fw); |
| if (ret) |
| return ret; |
| |
| ehdr = (struct elf32_hdr *)fw->data; |
| |
| dev_info(dev, "Booting fw image %s, size %d\n", name, fw->size); |
| |
| /* |
| * if enabling an IOMMU isn't relevant for this rproc, this is |
| * just a nop |
| */ |
| ret = rproc_enable_iommu(rproc); |
| if (ret) { |
| dev_err(dev, "can't enable iommu: %d\n", ret); |
| return ret; |
| } |
| |
| /* |
| * The ELF entry point is the rproc's boot addr (though this is not |
| * a configurable property of all remote processors: some will always |
| * boot at a specific hardcoded address). |
| */ |
| rproc->bootaddr = ehdr->e_entry; |
| |
| /* handle fw resources which are required to boot rproc */ |
| ret = rproc_handle_resources(rproc, fw->data, fw->size, |
| rproc_handle_boot_rsc); |
| if (ret) { |
| dev_err(dev, "Failed to process resources: %d\n", ret); |
| goto clean_up; |
| } |
| |
| /* load the ELF segments to memory */ |
| ret = rproc_load_segments(rproc, fw->data, fw->size); |
| if (ret) { |
| dev_err(dev, "Failed to load program segments: %d\n", ret); |
| goto clean_up; |
| } |
| |
| /* power up the remote processor */ |
| ret = rproc->ops->start(rproc); |
| if (ret) { |
| dev_err(dev, "can't start rproc %s: %d\n", rproc->name, ret); |
| goto clean_up; |
| } |
| |
| rproc->state = RPROC_RUNNING; |
| |
| dev_info(dev, "remote processor %s is now up\n", rproc->name); |
| |
| return 0; |
| |
| clean_up: |
| rproc_resource_cleanup(rproc); |
| rproc_disable_iommu(rproc); |
| return ret; |
| } |
| |
| /* |
| * take a firmware and look for virtio devices to register. |
| * |
| * Note: this function is called asynchronously upon registration of the |
| * remote processor (so we must wait until it completes before we try |
| * to unregister the device. one other option is just to use kref here, |
| * that might be cleaner). |
| */ |
| static void rproc_fw_config_virtio(const struct firmware *fw, void *context) |
| { |
| struct rproc *rproc = context; |
| struct device *dev = rproc->dev; |
| int ret; |
| |
| if (rproc_fw_sanity_check(rproc, fw) < 0) |
| goto out; |
| |
| /* does the fw supports any virtio devices ? */ |
| ret = rproc_handle_resources(rproc, fw->data, fw->size, |
| rproc_handle_virtio_rsc); |
| if (ret) { |
| dev_info(dev, "No fw virtio device was found\n"); |
| goto out; |
| } |
| |
| /* add the virtio device (currently only rpmsg vdevs are supported) */ |
| ret = rproc_add_rpmsg_vdev(rproc); |
| if (ret) |
| goto out; |
| |
| out: |
| if (fw) |
| release_firmware(fw); |
| /* allow rproc_unregister() contexts, if any, to proceed */ |
| complete_all(&rproc->firmware_loading_complete); |
| } |
| |
| /** |
| * rproc_boot() - boot a remote processor |
| * @rproc: handle of a remote processor |
| * |
| * Boot a remote processor (i.e. load its firmware, power it on, ...). |
| * |
| * If the remote processor is already powered on, this function immediately |
| * returns (successfully). |
| * |
| * Returns 0 on success, and an appropriate error value otherwise. |
| */ |
| int rproc_boot(struct rproc *rproc) |
| { |
| const struct firmware *firmware_p; |
| struct device *dev; |
| int ret; |
| |
| if (!rproc) { |
| pr_err("invalid rproc handle\n"); |
| return -EINVAL; |
| } |
| |
| dev = rproc->dev; |
| |
| ret = mutex_lock_interruptible(&rproc->lock); |
| if (ret) { |
| dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret); |
| return ret; |
| } |
| |
| /* loading a firmware is required */ |
| if (!rproc->firmware) { |
| dev_err(dev, "%s: no firmware to load\n", __func__); |
| ret = -EINVAL; |
| goto unlock_mutex; |
| } |
| |
| /* prevent underlying implementation from being removed */ |
| if (!try_module_get(dev->driver->owner)) { |
| dev_err(dev, "%s: can't get owner\n", __func__); |
| ret = -EINVAL; |
| goto unlock_mutex; |
| } |
| |
| /* skip the boot process if rproc is already powered up */ |
| if (atomic_inc_return(&rproc->power) > 1) { |
| ret = 0; |
| goto unlock_mutex; |
| } |
| |
| dev_info(dev, "powering up %s\n", rproc->name); |
| |
| /* load firmware */ |
| ret = request_firmware(&firmware_p, rproc->firmware, dev); |
| if (ret < 0) { |
| dev_err(dev, "request_firmware failed: %d\n", ret); |
| goto downref_rproc; |
| } |
| |
| ret = rproc_fw_boot(rproc, firmware_p); |
| |
| release_firmware(firmware_p); |
| |
| downref_rproc: |
| if (ret) { |
| module_put(dev->driver->owner); |
| atomic_dec(&rproc->power); |
| } |
| unlock_mutex: |
| mutex_unlock(&rproc->lock); |
| return ret; |
| } |
| EXPORT_SYMBOL(rproc_boot); |
| |
| /** |
| * rproc_shutdown() - power off the remote processor |
| * @rproc: the remote processor |
| * |
| * Power off a remote processor (previously booted with rproc_boot()). |
| * |
| * In case @rproc is still being used by an additional user(s), then |
| * this function will just decrement the power refcount and exit, |
| * without really powering off the device. |
| * |
| * Every call to rproc_boot() must (eventually) be accompanied by a call |
| * to rproc_shutdown(). Calling rproc_shutdown() redundantly is a bug. |
| * |
| * Notes: |
| * - we're not decrementing the rproc's refcount, only the power refcount. |
| * which means that the @rproc handle stays valid even after rproc_shutdown() |
| * returns, and users can still use it with a subsequent rproc_boot(), if |
| * needed. |
| * - don't call rproc_shutdown() to unroll rproc_get_by_name(), exactly |
| * because rproc_shutdown() _does not_ decrement the refcount of @rproc. |
| * To decrement the refcount of @rproc, use rproc_put() (but _only_ if |
| * you acquired @rproc using rproc_get_by_name()). |
| */ |
| void rproc_shutdown(struct rproc *rproc) |
| { |
| struct device *dev = rproc->dev; |
| int ret; |
| |
| ret = mutex_lock_interruptible(&rproc->lock); |
| if (ret) { |
| dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret); |
| return; |
| } |
| |
| /* if the remote proc is still needed, bail out */ |
| if (!atomic_dec_and_test(&rproc->power)) |
| goto out; |
| |
| /* power off the remote processor */ |
| ret = rproc->ops->stop(rproc); |
| if (ret) { |
| atomic_inc(&rproc->power); |
| dev_err(dev, "can't stop rproc: %d\n", ret); |
| goto out; |
| } |
| |
| /* clean up all acquired resources */ |
| rproc_resource_cleanup(rproc); |
| |
| rproc_disable_iommu(rproc); |
| |
| rproc->state = RPROC_OFFLINE; |
| |
| dev_info(dev, "stopped remote processor %s\n", rproc->name); |
| |
| out: |
| mutex_unlock(&rproc->lock); |
| if (!ret) |
| module_put(dev->driver->owner); |
| } |
| EXPORT_SYMBOL(rproc_shutdown); |
| |
| /** |
| * rproc_release() - completely deletes the existence of a remote processor |
| * @kref: the rproc's kref |
| * |
| * This function should _never_ be called directly. |
| * |
| * The only reasonable location to use it is as an argument when kref_put'ing |
| * @rproc's refcount. |
| * |
| * This way it will be called when no one holds a valid pointer to this @rproc |
| * anymore (and obviously after it is removed from the rprocs klist). |
| * |
| * Note: this function is not static because rproc_vdev_release() needs it when |
| * it decrements @rproc's refcount. |
| */ |
| void rproc_release(struct kref *kref) |
| { |
| struct rproc *rproc = container_of(kref, struct rproc, refcount); |
| |
| dev_info(rproc->dev, "removing %s\n", rproc->name); |
| |
| rproc_delete_debug_dir(rproc); |
| |
| /* at this point no one holds a reference to rproc anymore */ |
| kfree(rproc); |
| } |
| |
| /* will be called when an rproc is added to the rprocs klist */ |
| static void klist_rproc_get(struct klist_node *n) |
| { |
| struct rproc *rproc = container_of(n, struct rproc, node); |
| |
| kref_get(&rproc->refcount); |
| } |
| |
| /* will be called when an rproc is removed from the rprocs klist */ |
| static void klist_rproc_put(struct klist_node *n) |
| { |
| struct rproc *rproc = container_of(n, struct rproc, node); |
| |
| kref_put(&rproc->refcount, rproc_release); |
| } |
| |
| static struct rproc *next_rproc(struct klist_iter *i) |
| { |
| struct klist_node *n; |
| |
| n = klist_next(i); |
| if (!n) |
| return NULL; |
| |
| return container_of(n, struct rproc, node); |
| } |
| |
| /** |
| * rproc_get_by_name() - find a remote processor by name and boot it |
| * @name: name of the remote processor |
| * |
| * Finds an rproc handle using the remote processor's name, and then |
| * boot it. If it's already powered on, then just immediately return |
| * (successfully). |
| * |
| * Returns the rproc handle on success, and NULL on failure. |
| * |
| * This function increments the remote processor's refcount, so always |
| * use rproc_put() to decrement it back once rproc isn't needed anymore. |
| * |
| * Note: currently this function (and its counterpart rproc_put()) are not |
| * used anymore by the rpmsg subsystem. We need to scrutinize the use cases |
| * that still need them, and see if we can migrate them to use the non |
| * name-based boot/shutdown interface. |
| */ |
| struct rproc *rproc_get_by_name(const char *name) |
| { |
| struct rproc *rproc; |
| struct klist_iter i; |
| int ret; |
| |
| /* find the remote processor, and upref its refcount */ |
| klist_iter_init(&rprocs, &i); |
| while ((rproc = next_rproc(&i)) != NULL) |
| if (!strcmp(rproc->name, name)) { |
| kref_get(&rproc->refcount); |
| break; |
| } |
| klist_iter_exit(&i); |
| |
| /* can't find this rproc ? */ |
| if (!rproc) { |
| pr_err("can't find remote processor %s\n", name); |
| return NULL; |
| } |
| |
| ret = rproc_boot(rproc); |
| if (ret < 0) { |
| kref_put(&rproc->refcount, rproc_release); |
| return NULL; |
| } |
| |
| return rproc; |
| } |
| EXPORT_SYMBOL(rproc_get_by_name); |
| |
| /** |
| * rproc_put() - decrement the refcount of a remote processor, and shut it down |
| * @rproc: the remote processor |
| * |
| * This function tries to shutdown @rproc, and it then decrements its |
| * refcount. |
| * |
| * After this function returns, @rproc may _not_ be used anymore, and its |
| * handle should be considered invalid. |
| * |
| * This function should be called _iff_ the @rproc handle was grabbed by |
| * calling rproc_get_by_name(). |
| */ |
| void rproc_put(struct rproc *rproc) |
| { |
| /* try to power off the remote processor */ |
| rproc_shutdown(rproc); |
| |
| /* downref rproc's refcount */ |
| kref_put(&rproc->refcount, rproc_release); |
| } |
| EXPORT_SYMBOL(rproc_put); |
| |
| /** |
| * rproc_register() - register a remote processor |
| * @rproc: the remote processor handle to register |
| * |
| * Registers @rproc with the remoteproc framework, after it has been |
| * allocated with rproc_alloc(). |
| * |
| * This is called by the platform-specific rproc implementation, whenever |
| * a new remote processor device is probed. |
| * |
| * Returns 0 on success and an appropriate error code otherwise. |
| * |
| * Note: this function initiates an asynchronous firmware loading |
| * context, which will look for virtio devices supported by the rproc's |
| * firmware. |
| * |
| * If found, those virtio devices will be created and added, so as a result |
| * of registering this remote processor, additional virtio drivers will be |
| * probed. |
| * |
| * Currently, though, we only support a single RPMSG virtio vdev per remote |
| * processor. |
| */ |
| int rproc_register(struct rproc *rproc) |
| { |
| struct device *dev = rproc->dev; |
| int ret = 0; |
| |
| /* expose to rproc_get_by_name users */ |
| klist_add_tail(&rproc->node, &rprocs); |
| |
| dev_info(rproc->dev, "%s is available\n", rproc->name); |
| |
| /* create debugfs entries */ |
| rproc_create_debug_dir(rproc); |
| |
| /* rproc_unregister() calls must wait until async loader completes */ |
| init_completion(&rproc->firmware_loading_complete); |
| |
| /* |
| * We must retrieve early virtio configuration info from |
| * the firmware (e.g. whether to register a virtio rpmsg device, |
| * what virtio features does it support, ...). |
| * |
| * We're initiating an asynchronous firmware loading, so we can |
| * be built-in kernel code, without hanging the boot process. |
| */ |
| ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_HOTPLUG, |
| rproc->firmware, dev, GFP_KERNEL, |
| rproc, rproc_fw_config_virtio); |
| if (ret < 0) { |
| dev_err(dev, "request_firmware_nowait failed: %d\n", ret); |
| complete_all(&rproc->firmware_loading_complete); |
| klist_remove(&rproc->node); |
| } |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(rproc_register); |
| |
| /** |
| * rproc_alloc() - allocate a remote processor handle |
| * @dev: the underlying device |
| * @name: name of this remote processor |
| * @ops: platform-specific handlers (mainly start/stop) |
| * @firmware: name of firmware file to load |
| * @len: length of private data needed by the rproc driver (in bytes) |
| * |
| * Allocates a new remote processor handle, but does not register |
| * it yet. |
| * |
| * This function should be used by rproc implementations during initialization |
| * of the remote processor. |
| * |
| * After creating an rproc handle using this function, and when ready, |
| * implementations should then call rproc_register() to complete |
| * the registration of the remote processor. |
| * |
| * On success the new rproc is returned, and on failure, NULL. |
| * |
| * Note: _never_ directly deallocate @rproc, even if it was not registered |
| * yet. Instead, if you just need to unroll rproc_alloc(), use rproc_free(). |
| */ |
| struct rproc *rproc_alloc(struct device *dev, const char *name, |
| const struct rproc_ops *ops, |
| const char *firmware, int len) |
| { |
| struct rproc *rproc; |
| |
| if (!dev || !name || !ops) |
| return NULL; |
| |
| rproc = kzalloc(sizeof(struct rproc) + len, GFP_KERNEL); |
| if (!rproc) { |
| dev_err(dev, "%s: kzalloc failed\n", __func__); |
| return NULL; |
| } |
| |
| rproc->dev = dev; |
| rproc->name = name; |
| rproc->ops = ops; |
| rproc->firmware = firmware; |
| rproc->priv = &rproc[1]; |
| |
| atomic_set(&rproc->power, 0); |
| |
| kref_init(&rproc->refcount); |
| |
| mutex_init(&rproc->lock); |
| |
| INIT_LIST_HEAD(&rproc->carveouts); |
| INIT_LIST_HEAD(&rproc->mappings); |
| INIT_LIST_HEAD(&rproc->traces); |
| |
| rproc->state = RPROC_OFFLINE; |
| |
| return rproc; |
| } |
| EXPORT_SYMBOL(rproc_alloc); |
| |
| /** |
| * rproc_free() - free an rproc handle that was allocated by rproc_alloc |
| * @rproc: the remote processor handle |
| * |
| * This function should _only_ be used if @rproc was only allocated, |
| * but not registered yet. |
| * |
| * If @rproc was already successfully registered (by calling rproc_register()), |
| * then use rproc_unregister() instead. |
| */ |
| void rproc_free(struct rproc *rproc) |
| { |
| kfree(rproc); |
| } |
| EXPORT_SYMBOL(rproc_free); |
| |
| /** |
| * rproc_unregister() - unregister a remote processor |
| * @rproc: rproc handle to unregister |
| * |
| * Unregisters a remote processor, and decrements its refcount. |
| * If its refcount drops to zero, then @rproc will be freed. If not, |
| * it will be freed later once the last reference is dropped. |
| * |
| * This function should be called when the platform specific rproc |
| * implementation decides to remove the rproc device. it should |
| * _only_ be called if a previous invocation of rproc_register() |
| * has completed successfully. |
| * |
| * After rproc_unregister() returns, @rproc is _not_ valid anymore and |
| * it shouldn't be used. More specifically, don't call rproc_free() |
| * or try to directly free @rproc after rproc_unregister() returns; |
| * none of these are needed, and calling them is a bug. |
| * |
| * Returns 0 on success and -EINVAL if @rproc isn't valid. |
| */ |
| int rproc_unregister(struct rproc *rproc) |
| { |
| if (!rproc) |
| return -EINVAL; |
| |
| /* if rproc is just being registered, wait */ |
| wait_for_completion(&rproc->firmware_loading_complete); |
| |
| /* was an rpmsg vdev created ? */ |
| if (rproc->rvdev) |
| rproc_remove_rpmsg_vdev(rproc); |
| |
| klist_remove(&rproc->node); |
| |
| kref_put(&rproc->refcount, rproc_release); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(rproc_unregister); |
| |
| static int __init remoteproc_init(void) |
| { |
| rproc_init_debugfs(); |
| return 0; |
| } |
| module_init(remoteproc_init); |
| |
| static void __exit remoteproc_exit(void) |
| { |
| rproc_exit_debugfs(); |
| } |
| module_exit(remoteproc_exit); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_DESCRIPTION("Generic Remote Processor Framework"); |