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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Remote Processor Framework ELF loader4 *5 * Copyright (C) 2011 Texas Instruments, Inc.6 * Copyright (C) 2011 Google, Inc.7 *8 * Ohad Ben-Cohen <ohad@wizery.com>9 * Brian Swetland <swetland@google.com>10 * Mark Grosen <mgrosen@ti.com>11 * Fernando Guzman Lugo <fernando.lugo@ti.com>12 * Suman Anna <s-anna@ti.com>13 * Robert Tivy <rtivy@ti.com>14 * Armando Uribe De Leon <x0095078@ti.com>15 * Sjur Brændeland <sjur.brandeland@stericsson.com>16 */17 18#define pr_fmt(fmt)    "%s: " fmt, __func__19 20#include <linux/module.h>21#include <linux/firmware.h>22#include <linux/remoteproc.h>23#include <linux/elf.h>24 25#include "remoteproc_internal.h"26#include "remoteproc_elf_helpers.h"27 28/**29 * rproc_elf_sanity_check() - Sanity Check for ELF32/ELF64 firmware image30 * @rproc: the remote processor handle31 * @fw: the ELF firmware image32 *33 * Make sure this fw image is sane (ie a correct ELF32/ELF64 file).34 *35 * Return: 0 on success and -EINVAL upon any failure36 */37int rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw)38{39	const char *name = rproc->firmware;40	struct device *dev = &rproc->dev;41	/*42	 * ELF files are beginning with the same structure. Thus, to simplify43	 * header parsing, we can use the elf32_hdr one for both elf64 and44	 * elf32.45	 */46	struct elf32_hdr *ehdr;47	u32 elf_shdr_get_size;48	u64 phoff, shoff;49	char class;50	u16 phnum;51 52	if (!fw) {53		dev_err(dev, "failed to load %s\n", name);54		return -EINVAL;55	}56 57	if (fw->size < sizeof(struct elf32_hdr)) {58		dev_err(dev, "Image is too small\n");59		return -EINVAL;60	}61 62	ehdr = (struct elf32_hdr *)fw->data;63 64	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {65		dev_err(dev, "Image is corrupted (bad magic)\n");66		return -EINVAL;67	}68 69	class = ehdr->e_ident[EI_CLASS];70	if (class != ELFCLASS32 && class != ELFCLASS64) {71		dev_err(dev, "Unsupported class: %d\n", class);72		return -EINVAL;73	}74 75	if (class == ELFCLASS64 && fw->size < sizeof(struct elf64_hdr)) {76		dev_err(dev, "elf64 header is too small\n");77		return -EINVAL;78	}79 80	/* We assume the firmware has the same endianness as the host */81# ifdef __LITTLE_ENDIAN82	if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB) {83# else /* BIG ENDIAN */84	if (ehdr->e_ident[EI_DATA] != ELFDATA2MSB) {85# endif86		dev_err(dev, "Unsupported firmware endianness\n");87		return -EINVAL;88	}89 90	phoff = elf_hdr_get_e_phoff(class, fw->data);91	shoff = elf_hdr_get_e_shoff(class, fw->data);92	phnum =  elf_hdr_get_e_phnum(class, fw->data);93	elf_shdr_get_size = elf_size_of_shdr(class);94 95	if (fw->size < shoff + elf_shdr_get_size) {96		dev_err(dev, "Image is too small\n");97		return -EINVAL;98	}99 100	if (phnum == 0) {101		dev_err(dev, "No loadable segments\n");102		return -EINVAL;103	}104 105	if (phoff > fw->size) {106		dev_err(dev, "Firmware size is too small\n");107		return -EINVAL;108	}109 110	dev_dbg(dev, "Firmware is an elf%d file\n",111		class == ELFCLASS32 ? 32 : 64);112 113	return 0;114}115EXPORT_SYMBOL(rproc_elf_sanity_check);116 117/**118 * rproc_elf_get_boot_addr() - Get rproc's boot address.119 * @rproc: the remote processor handle120 * @fw: the ELF firmware image121 *122 * Note that the boot address is not a configurable property of all remote123 * processors. Some will always boot at a specific hard-coded address.124 *125 * Return: entry point address of the ELF image126 *127 */128u64 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw)129{130	return elf_hdr_get_e_entry(fw_elf_get_class(fw), fw->data);131}132EXPORT_SYMBOL(rproc_elf_get_boot_addr);133 134/**135 * rproc_elf_load_segments() - load firmware segments to memory136 * @rproc: remote processor which will be booted using these fw segments137 * @fw: the ELF firmware image138 *139 * This function loads the firmware segments to memory, where the remote140 * processor expects them.141 *142 * Some remote processors will expect their code and data to be placed143 * in specific device addresses, and can't have them dynamically assigned.144 *145 * We currently support only those kind of remote processors, and expect146 * the program header's paddr member to contain those addresses. We then go147 * through the physically contiguous "carveout" memory regions which we148 * allocated (and mapped) earlier on behalf of the remote processor,149 * and "translate" device address to kernel addresses, so we can copy the150 * segments where they are expected.151 *152 * Currently we only support remote processors that required carveout153 * allocations and got them mapped onto their iommus. Some processors154 * might be different: they might not have iommus, and would prefer to155 * directly allocate memory for every segment/resource. This is not yet156 * supported, though.157 *158 * Return: 0 on success and an appropriate error code otherwise159 */160int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)161{162	struct device *dev = &rproc->dev;163	const void *ehdr, *phdr;164	int i, ret = 0;165	u16 phnum;166	const u8 *elf_data = fw->data;167	u8 class = fw_elf_get_class(fw);168	u32 elf_phdr_get_size = elf_size_of_phdr(class);169 170	ehdr = elf_data;171	phnum = elf_hdr_get_e_phnum(class, ehdr);172	phdr = elf_data + elf_hdr_get_e_phoff(class, ehdr);173 174	/* go through the available ELF segments */175	for (i = 0; i < phnum; i++, phdr += elf_phdr_get_size) {176		u64 da = elf_phdr_get_p_paddr(class, phdr);177		u64 memsz = elf_phdr_get_p_memsz(class, phdr);178		u64 filesz = elf_phdr_get_p_filesz(class, phdr);179		u64 offset = elf_phdr_get_p_offset(class, phdr);180		u32 type = elf_phdr_get_p_type(class, phdr);181		bool is_iomem = false;182		void *ptr;183 184		if (type != PT_LOAD || !memsz)185			continue;186 187		dev_dbg(dev, "phdr: type %d da 0x%llx memsz 0x%llx filesz 0x%llx\n",188			type, da, memsz, filesz);189 190		if (filesz > memsz) {191			dev_err(dev, "bad phdr filesz 0x%llx memsz 0x%llx\n",192				filesz, memsz);193			ret = -EINVAL;194			break;195		}196 197		if (offset + filesz > fw->size) {198			dev_err(dev, "truncated fw: need 0x%llx avail 0x%zx\n",199				offset + filesz, fw->size);200			ret = -EINVAL;201			break;202		}203 204		if (!rproc_u64_fit_in_size_t(memsz)) {205			dev_err(dev, "size (%llx) does not fit in size_t type\n",206				memsz);207			ret = -EOVERFLOW;208			break;209		}210 211		/* grab the kernel address for this device address */212		ptr = rproc_da_to_va(rproc, da, memsz, &is_iomem);213		if (!ptr) {214			dev_err(dev, "bad phdr da 0x%llx mem 0x%llx\n", da,215				memsz);216			ret = -EINVAL;217			break;218		}219 220		/* put the segment where the remote processor expects it */221		if (filesz) {222			if (is_iomem)223				memcpy_toio((void __iomem *)ptr, elf_data + offset, filesz);224			else225				memcpy(ptr, elf_data + offset, filesz);226		}227 228		/*229		 * Zero out remaining memory for this segment.230		 *231		 * This isn't strictly required since dma_alloc_coherent already232		 * did this for us. albeit harmless, we may consider removing233		 * this.234		 */235		if (memsz > filesz) {236			if (is_iomem)237				memset_io((void __iomem *)(ptr + filesz), 0, memsz - filesz);238			else239				memset(ptr + filesz, 0, memsz - filesz);240		}241	}242 243	return ret;244}245EXPORT_SYMBOL(rproc_elf_load_segments);246 247static const void *248find_table(struct device *dev, const struct firmware *fw)249{250	const void *shdr, *name_table_shdr;251	int i;252	const char *name_table;253	struct resource_table *table = NULL;254	const u8 *elf_data = (void *)fw->data;255	u8 class = fw_elf_get_class(fw);256	size_t fw_size = fw->size;257	const void *ehdr = elf_data;258	u16 shnum = elf_hdr_get_e_shnum(class, ehdr);259	u32 elf_shdr_get_size = elf_size_of_shdr(class);260	u16 shstrndx = elf_hdr_get_e_shstrndx(class, ehdr);261 262	/* look for the resource table and handle it */263	/* First, get the section header according to the elf class */264	shdr = elf_data + elf_hdr_get_e_shoff(class, ehdr);265	/* Compute name table section header entry in shdr array */266	name_table_shdr = shdr + (shstrndx * elf_shdr_get_size);267	/* Finally, compute the name table section address in elf */268	name_table = elf_data + elf_shdr_get_sh_offset(class, name_table_shdr);269 270	for (i = 0; i < shnum; i++, shdr += elf_shdr_get_size) {271		u64 size = elf_shdr_get_sh_size(class, shdr);272		u64 offset = elf_shdr_get_sh_offset(class, shdr);273		u32 name = elf_shdr_get_sh_name(class, shdr);274 275		if (strcmp(name_table + name, ".resource_table"))276			continue;277 278		table = (struct resource_table *)(elf_data + offset);279 280		/* make sure we have the entire table */281		if (offset + size > fw_size || offset + size < size) {282			dev_err(dev, "resource table truncated\n");283			return NULL;284		}285 286		/* make sure table has at least the header */287		if (sizeof(struct resource_table) > size) {288			dev_err(dev, "header-less resource table\n");289			return NULL;290		}291 292		/* we don't support any version beyond the first */293		if (table->ver != 1) {294			dev_err(dev, "unsupported fw ver: %d\n", table->ver);295			return NULL;296		}297 298		/* make sure reserved bytes are zeroes */299		if (table->reserved[0] || table->reserved[1]) {300			dev_err(dev, "non zero reserved bytes\n");301			return NULL;302		}303 304		/* make sure the offsets array isn't truncated */305		if (struct_size(table, offset, table->num) > size) {306			dev_err(dev, "resource table incomplete\n");307			return NULL;308		}309 310		return shdr;311	}312 313	return NULL;314}315 316/**317 * rproc_elf_load_rsc_table() - load the resource table318 * @rproc: the rproc handle319 * @fw: the ELF firmware image320 *321 * This function finds the resource table inside the remote processor's322 * firmware, load it into the @cached_table and update @table_ptr.323 *324 * Return: 0 on success, negative errno on failure.325 */326int rproc_elf_load_rsc_table(struct rproc *rproc, const struct firmware *fw)327{328	const void *shdr;329	struct device *dev = &rproc->dev;330	struct resource_table *table = NULL;331	const u8 *elf_data = fw->data;332	size_t tablesz;333	u8 class = fw_elf_get_class(fw);334	u64 sh_offset;335 336	shdr = find_table(dev, fw);337	if (!shdr)338		return -EINVAL;339 340	sh_offset = elf_shdr_get_sh_offset(class, shdr);341	table = (struct resource_table *)(elf_data + sh_offset);342	tablesz = elf_shdr_get_sh_size(class, shdr);343 344	/*345	 * Create a copy of the resource table. When a virtio device starts346	 * and calls vring_new_virtqueue() the address of the allocated vring347	 * will be stored in the cached_table. Before the device is started,348	 * cached_table will be copied into device memory.349	 */350	rproc->cached_table = kmemdup(table, tablesz, GFP_KERNEL);351	if (!rproc->cached_table)352		return -ENOMEM;353 354	rproc->table_ptr = rproc->cached_table;355	rproc->table_sz = tablesz;356 357	return 0;358}359EXPORT_SYMBOL(rproc_elf_load_rsc_table);360 361/**362 * rproc_elf_find_loaded_rsc_table() - find the loaded resource table363 * @rproc: the rproc handle364 * @fw: the ELF firmware image365 *366 * This function finds the location of the loaded resource table. Don't367 * call this function if the table wasn't loaded yet - it's a bug if you do.368 *369 * Return: pointer to the resource table if it is found or NULL otherwise.370 * If the table wasn't loaded yet the result is unspecified.371 */372struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,373						       const struct firmware *fw)374{375	const void *shdr;376	u64 sh_addr, sh_size;377	u8 class = fw_elf_get_class(fw);378	struct device *dev = &rproc->dev;379 380	shdr = find_table(&rproc->dev, fw);381	if (!shdr)382		return NULL;383 384	sh_addr = elf_shdr_get_sh_addr(class, shdr);385	sh_size = elf_shdr_get_sh_size(class, shdr);386 387	if (!rproc_u64_fit_in_size_t(sh_size)) {388		dev_err(dev, "size (%llx) does not fit in size_t type\n",389			sh_size);390		return NULL;391	}392 393	return rproc_da_to_va(rproc, sh_addr, sh_size, NULL);394}395EXPORT_SYMBOL(rproc_elf_find_loaded_rsc_table);396