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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /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.c337
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
+};