1 files changed, 395 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..5a412d7b6
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_elf_loader.c
@@ -0,0 +1,395 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+#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"
+#include "remoteproc_elf_helpers.h"
+
+/**
+ * rproc_elf_sanity_check() - Sanity Check for ELF32/ELF64 firmware image
+ * @rproc: the remote processor handle
+ * @fw: the ELF firmware image
+ *
+ * Make sure this fw image is sane (ie a correct ELF32/ELF64 file).
+ *
+ * Return: 0 on success and -EINVAL upon any failure
+ */
+int rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw)
+{
+	const char *name = rproc->firmware;
+	struct device *dev = &rproc->dev;
+	/*
+	 * Elf files are beginning with the same structure. Thus, to simplify
+	 * header parsing, we can use the elf32_hdr one for both elf64 and
+	 * elf32.
+	 */
+	struct elf32_hdr *ehdr;
+	u32 elf_shdr_get_size;
+	u64 phoff, shoff;
+	char class;
+	u16 phnum;
+
+	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;
+
+	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
+		dev_err(dev, "Image is corrupted (bad magic)\n");
+		return -EINVAL;
+	}
+
+	class = ehdr->e_ident[EI_CLASS];
+	if (class != ELFCLASS32 && class != ELFCLASS64) {
+		dev_err(dev, "Unsupported class: %d\n", class);
+		return -EINVAL;
+	}
+
+	if (class == ELFCLASS64 && fw->size < sizeof(struct elf64_hdr)) {
+		dev_err(dev, "elf64 header is too small\n");
+		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;
+	}
+
+	phoff = elf_hdr_get_e_phoff(class, fw->data);
+	shoff = elf_hdr_get_e_shoff(class, fw->data);
+	phnum =  elf_hdr_get_e_phnum(class, fw->data);
+	elf_shdr_get_size = elf_size_of_shdr(class);
+
+	if (fw->size < shoff + elf_shdr_get_size) {
+		dev_err(dev, "Image is too small\n");
+		return -EINVAL;
+	}
+
+	if (phnum == 0) {
+		dev_err(dev, "No loadable segments\n");
+		return -EINVAL;
+	}
+
+	if (phoff > fw->size) {
+		dev_err(dev, "Firmware size is too small\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "Firmware is an elf%d file\n",
+		class == ELFCLASS32 ? 32 : 64);
+
+	return 0;
+}
+EXPORT_SYMBOL(rproc_elf_sanity_check);
+
+/**
+ * rproc_elf_get_boot_addr() - Get rproc's boot address.
+ * @rproc: the remote processor handle
+ * @fw: the ELF firmware 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.
+ *
+ * Return: entry point address of the ELF image
+ *
+ */
+u64 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw)
+{
+	return elf_hdr_get_e_entry(fw_elf_get_class(fw), fw->data);
+}
+EXPORT_SYMBOL(rproc_elf_get_boot_addr);
+
+/**
+ * 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.
+ *
+ * Return: 0 on success and an appropriate error code otherwise
+ */
+int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
+{
+	struct device *dev = &rproc->dev;
+	const void *ehdr, *phdr;
+	int i, ret = 0;
+	u16 phnum;
+	const u8 *elf_data = fw->data;
+	u8 class = fw_elf_get_class(fw);
+	u32 elf_phdr_get_size = elf_size_of_phdr(class);
+
+	ehdr = elf_data;
+	phnum = elf_hdr_get_e_phnum(class, ehdr);
+	phdr = elf_data + elf_hdr_get_e_phoff(class, ehdr);
+
+	/* go through the available ELF segments */
+	for (i = 0; i < phnum; i++, phdr += elf_phdr_get_size) {
+		u64 da = elf_phdr_get_p_paddr(class, phdr);
+		u64 memsz = elf_phdr_get_p_memsz(class, phdr);
+		u64 filesz = elf_phdr_get_p_filesz(class, phdr);
+		u64 offset = elf_phdr_get_p_offset(class, phdr);
+		u32 type = elf_phdr_get_p_type(class, phdr);
+		bool is_iomem = false;
+		void *ptr;
+
+		if (type != PT_LOAD || !memsz)
+			continue;
+
+		dev_dbg(dev, "phdr: type %d da 0x%llx memsz 0x%llx filesz 0x%llx\n",
+			type, da, memsz, filesz);
+
+		if (filesz > memsz) {
+			dev_err(dev, "bad phdr filesz 0x%llx memsz 0x%llx\n",
+				filesz, memsz);
+			ret = -EINVAL;
+			break;
+		}
+
+		if (offset + filesz > fw->size) {
+			dev_err(dev, "truncated fw: need 0x%llx avail 0x%zx\n",
+				offset + filesz, fw->size);
+			ret = -EINVAL;
+			break;
+		}
+
+		if (!rproc_u64_fit_in_size_t(memsz)) {
+			dev_err(dev, "size (%llx) does not fit in size_t type\n",
+				memsz);
+			ret = -EOVERFLOW;
+			break;
+		}
+
+		/* grab the kernel address for this device address */
+		ptr = rproc_da_to_va(rproc, da, memsz, &is_iomem);
+		if (!ptr) {
+			dev_err(dev, "bad phdr da 0x%llx mem 0x%llx\n", da,
+				memsz);
+			ret = -EINVAL;
+			break;
+		}
+
+		/* put the segment where the remote processor expects it */
+		if (filesz) {
+			if (is_iomem)
+				memcpy_toio((void __iomem *)ptr, elf_data + offset, filesz);
+			else
+				memcpy(ptr, elf_data + 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) {
+			if (is_iomem)
+				memset_io((void __iomem *)(ptr + filesz), 0, memsz - filesz);
+			else
+				memset(ptr + filesz, 0, memsz - filesz);
+		}
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(rproc_elf_load_segments);
+
+static const void *
+find_table(struct device *dev, const struct firmware *fw)
+{
+	const void *shdr, *name_table_shdr;
+	int i;
+	const char *name_table;
+	struct resource_table *table = NULL;
+	const u8 *elf_data = (void *)fw->data;
+	u8 class = fw_elf_get_class(fw);
+	size_t fw_size = fw->size;
+	const void *ehdr = elf_data;
+	u16 shnum = elf_hdr_get_e_shnum(class, ehdr);
+	u32 elf_shdr_get_size = elf_size_of_shdr(class);
+	u16 shstrndx = elf_hdr_get_e_shstrndx(class, ehdr);
+
+	/* look for the resource table and handle it */
+	/* First, get the section header according to the elf class */
+	shdr = elf_data + elf_hdr_get_e_shoff(class, ehdr);
+	/* Compute name table section header entry in shdr array */
+	name_table_shdr = shdr + (shstrndx * elf_shdr_get_size);
+	/* Finally, compute the name table section address in elf */
+	name_table = elf_data + elf_shdr_get_sh_offset(class, name_table_shdr);
+
+	for (i = 0; i < shnum; i++, shdr += elf_shdr_get_size) {
+		u64 size = elf_shdr_get_sh_size(class, shdr);
+		u64 offset = elf_shdr_get_sh_offset(class, shdr);
+		u32 name = elf_shdr_get_sh_name(class, shdr);
+
+		if (strcmp(name_table + 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 (struct_size(table, offset, table->num) > size) {
+			dev_err(dev, "resource table incomplete\n");
+			return NULL;
+		}
+
+		return shdr;
+	}
+
+	return NULL;
+}
+
+/**
+ * rproc_elf_load_rsc_table() - load the resource table
+ * @rproc: the rproc handle
+ * @fw: the ELF firmware image
+ *
+ * This function finds the resource table inside the remote processor's
+ * firmware, load it into the @cached_table and update @table_ptr.
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+int rproc_elf_load_rsc_table(struct rproc *rproc, const struct firmware *fw)
+{
+	const void *shdr;
+	struct device *dev = &rproc->dev;
+	struct resource_table *table = NULL;
+	const u8 *elf_data = fw->data;
+	size_t tablesz;
+	u8 class = fw_elf_get_class(fw);
+	u64 sh_offset;
+
+	shdr = find_table(dev, fw);
+	if (!shdr)
+		return -EINVAL;
+
+	sh_offset = elf_shdr_get_sh_offset(class, shdr);
+	table = (struct resource_table *)(elf_data + sh_offset);
+	tablesz = elf_shdr_get_sh_size(class, shdr);
+
+	/*
+	 * Create a copy of the resource table. When a virtio device starts
+	 * and calls vring_new_virtqueue() the address of the allocated vring
+	 * will be stored in the cached_table. Before the device is started,
+	 * cached_table will be copied into device memory.
+	 */
+	rproc->cached_table = kmemdup(table, tablesz, GFP_KERNEL);
+	if (!rproc->cached_table)
+		return -ENOMEM;
+
+	rproc->table_ptr = rproc->cached_table;
+	rproc->table_sz = tablesz;
+
+	return 0;
+}
+EXPORT_SYMBOL(rproc_elf_load_rsc_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.
+ *
+ * Return: pointer to the resource table if it is found or NULL otherwise.
+ * If the table wasn't loaded yet the result is unspecified.
+ */
+struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,
+						       const struct firmware *fw)
+{
+	const void *shdr;
+	u64 sh_addr, sh_size;
+	u8 class = fw_elf_get_class(fw);
+	struct device *dev = &rproc->dev;
+
+	shdr = find_table(&rproc->dev, fw);
+	if (!shdr)
+		return NULL;
+
+	sh_addr = elf_shdr_get_sh_addr(class, shdr);
+	sh_size = elf_shdr_get_sh_size(class, shdr);
+
+	if (!rproc_u64_fit_in_size_t(sh_size)) {
+		dev_err(dev, "size (%llx) does not fit in size_t type\n",
+			sh_size);
+		return NULL;
+	}
+
+	return rproc_da_to_va(rproc, sh_addr, sh_size, NULL);
+}
+EXPORT_SYMBOL(rproc_elf_find_loaded_rsc_table);