/*
* 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 endianess 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 endianess\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;
}
/**
* 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;
const char *name_table;
struct device *dev = &rproc->dev;
struct resource_table *table = NULL;
int i;
const u8 *elf_data = fw->data;
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++) {
int size = shdr->sh_size;
int 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) {
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;
}
*tablesz = shdr->sh_size;
break;
}
return table;
}
const struct rproc_fw_ops rproc_elf_fw_ops = {
.load = rproc_elf_load_segments,
.find_rsc_table = rproc_elf_find_rsc_table,
.sanity_check = rproc_elf_sanity_check,
.get_boot_addr = rproc_elf_get_boot_addr
};
