diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/remoteproc/remoteproc_elf_loader.c |
Initial import
Diffstat (limited to 'drivers/remoteproc/remoteproc_elf_loader.c')
-rw-r--r-- | drivers/remoteproc/remoteproc_elf_loader.c | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/drivers/remoteproc/remoteproc_elf_loader.c b/drivers/remoteproc/remoteproc_elf_loader.c new file mode 100644 index 000000000..ce283a5b4 --- /dev/null +++ b/drivers/remoteproc/remoteproc_elf_loader.c @@ -0,0 +1,337 @@ +/* + * Remote Processor Framework Elf loader + * + * 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> + * Sjur Brændeland <sjur.brandeland@stericsson.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/module.h> +#include <linux/firmware.h> +#include <linux/remoteproc.h> +#include <linux/elf.h> + +#include "remoteproc_internal.h" + +/** + * rproc_elf_sanity_check() - Sanity Check ELF firmware image + * @rproc: the remote processor handle + * @fw: the ELF firmware image + * + * Make sure this fw image is sane. + */ +static int +rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw) +{ + const char *name = rproc->firmware; + struct device *dev = &rproc->dev; + struct elf32_hdr *ehdr; + char class; + + 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; + + /* We only support ELF32 at this point */ + class = ehdr->e_ident[EI_CLASS]; + if (class != ELFCLASS32) { + dev_err(dev, "Unsupported class: %d\n", class); + return -EINVAL; + } + + /* We assume the firmware has the same endianness as the host */ +# ifdef __LITTLE_ENDIAN + if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB) { +# else /* BIG ENDIAN */ + if (ehdr->e_ident[EI_DATA] != ELFDATA2MSB) { +# endif + dev_err(dev, "Unsupported firmware endianness\n"); + return -EINVAL; + } + + 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; +} + +/** + * rproc_elf_get_boot_addr() - Get rproc's boot address. + * @rproc: the remote processor handle + * @fw: the ELF firmware image + * + * This function returns the entry point address of the ELF + * image. + * + * Note that the boot address is not a configurable property of all remote + * processors. Some will always boot at a specific hard-coded address. + */ +static +u32 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw) +{ + struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data; + + return ehdr->e_entry; +} + +/** + * rproc_elf_load_segments() - load firmware segments to memory + * @rproc: remote processor which will be booted using these fw segments + * @fw: the ELF firmware image + * + * This function loads the firmware segments to memory, where the remote + * processor expects them. + * + * Some remote processors will expect their code and data to be placed + * in specific device addresses, and can't have them dynamically assigned. + * + * We currently support only those kind of remote processors, and expect + * the program header's paddr member to contain those addresses. We then go + * through the physically contiguous "carveout" memory regions which we + * allocated (and mapped) earlier on behalf of the remote processor, + * and "translate" device address to kernel addresses, so we can copy the + * segments where they are expected. + * + * Currently we only support remote processors that required carveout + * allocations and got them mapped onto their iommus. Some processors + * might be different: they might not have iommus, and would prefer to + * directly allocate memory for every segment/resource. This is not yet + * supported, though. + */ +static int +rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw) +{ + struct device *dev = &rproc->dev; + struct elf32_hdr *ehdr; + struct elf32_phdr *phdr; + int i, ret = 0; + const u8 *elf_data = fw->data; + + 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 > fw->size) { + dev_err(dev, "truncated fw: need 0x%x avail 0x%zx\n", + offset + filesz, fw->size); + 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; +} + +static struct elf32_shdr * +find_table(struct device *dev, struct elf32_hdr *ehdr, size_t fw_size) +{ + struct elf32_shdr *shdr; + int i; + const char *name_table; + struct resource_table *table = NULL; + const u8 *elf_data = (void *)ehdr; + + /* look for the resource table and handle it */ + shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff); + name_table = elf_data + shdr[ehdr->e_shstrndx].sh_offset; + + for (i = 0; i < ehdr->e_shnum; i++, shdr++) { + u32 size = shdr->sh_size; + u32 offset = shdr->sh_offset; + + if (strcmp(name_table + shdr->sh_name, ".resource_table")) + continue; + + table = (struct resource_table *)(elf_data + offset); + + /* make sure we have the entire table */ + if (offset + size > fw_size || offset + size < size) { + dev_err(dev, "resource table truncated\n"); + return NULL; + } + + /* make sure table has at least the header */ + if (sizeof(struct resource_table) > size) { + dev_err(dev, "header-less resource table\n"); + return NULL; + } + + /* we don't support any version beyond the first */ + if (table->ver != 1) { + dev_err(dev, "unsupported fw ver: %d\n", table->ver); + return NULL; + } + + /* make sure reserved bytes are zeroes */ + if (table->reserved[0] || table->reserved[1]) { + dev_err(dev, "non zero reserved bytes\n"); + return NULL; + } + + /* make sure the offsets array isn't truncated */ + if (table->num * sizeof(table->offset[0]) + + sizeof(struct resource_table) > size) { + dev_err(dev, "resource table incomplete\n"); + return NULL; + } + + return shdr; + } + + return NULL; +} + +/** + * rproc_elf_find_rsc_table() - find the resource table + * @rproc: the rproc handle + * @fw: the ELF firmware image + * @tablesz: place holder for providing back the table size + * + * This function finds the resource table inside the remote processor's + * firmware. It is used both upon the registration of @rproc (in order + * to look for and register the supported virito devices), and when the + * @rproc is booted. + * + * Returns the pointer to the resource table if it is found, and write its + * size into @tablesz. If a valid table isn't found, NULL is returned + * (and @tablesz isn't set). + */ +static struct resource_table * +rproc_elf_find_rsc_table(struct rproc *rproc, const struct firmware *fw, + int *tablesz) +{ + struct elf32_hdr *ehdr; + struct elf32_shdr *shdr; + struct device *dev = &rproc->dev; + struct resource_table *table = NULL; + const u8 *elf_data = fw->data; + + ehdr = (struct elf32_hdr *)elf_data; + + shdr = find_table(dev, ehdr, fw->size); + if (!shdr) + return NULL; + + table = (struct resource_table *)(elf_data + shdr->sh_offset); + *tablesz = shdr->sh_size; + + return table; +} + +/** + * rproc_elf_find_loaded_rsc_table() - find the loaded resource table + * @rproc: the rproc handle + * @fw: the ELF firmware image + * + * This function finds the location of the loaded resource table. Don't + * call this function if the table wasn't loaded yet - it's a bug if you do. + * + * Returns the pointer to the resource table if it is found or NULL otherwise. + * If the table wasn't loaded yet the result is unspecified. + */ +static struct resource_table * +rproc_elf_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw) +{ + struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data; + struct elf32_shdr *shdr; + + shdr = find_table(&rproc->dev, ehdr, fw->size); + if (!shdr) + return NULL; + + return rproc_da_to_va(rproc, shdr->sh_addr, shdr->sh_size); +} + +const struct rproc_fw_ops rproc_elf_fw_ops = { + .load = rproc_elf_load_segments, + .find_rsc_table = rproc_elf_find_rsc_table, + .find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table, + .sanity_check = rproc_elf_sanity_check, + .get_boot_addr = rproc_elf_get_boot_addr +}; |