drivers/remoteproc/remoteproc_elf_loader.c - maze/linux - Git at Google

 /*
  * 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
 };
	/*
	* 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
	};