diff options
Diffstat (limited to 'drivers/soc/qcom/mdt_loader.c')
| -rw-r--r-- | drivers/soc/qcom/mdt_loader.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c new file mode 100644 index 0000000000..6f177e46fa --- /dev/null +++ b/drivers/soc/qcom/mdt_loader.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Qualcomm Peripheral Image Loader + * + * Copyright (C) 2016 Linaro Ltd + * Copyright (C) 2015 Sony Mobile Communications Inc + * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. + */ + +#include <linux/device.h> +#include <linux/elf.h> +#include <linux/firmware.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/firmware/qcom/qcom_scm.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/soc/qcom/mdt_loader.h> + +static bool mdt_phdr_valid(const struct elf32_phdr *phdr) +{ + if (phdr->p_type != PT_LOAD) + return false; + + if ((phdr->p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH) + return false; + + if (!phdr->p_memsz) + return false; + + return true; +} + +static ssize_t mdt_load_split_segment(void *ptr, const struct elf32_phdr *phdrs, + unsigned int segment, const char *fw_name, + struct device *dev) +{ + const struct elf32_phdr *phdr = &phdrs[segment]; + const struct firmware *seg_fw; + char *seg_name; + ssize_t ret; + + if (strlen(fw_name) < 4) + return -EINVAL; + + seg_name = kstrdup(fw_name, GFP_KERNEL); + if (!seg_name) + return -ENOMEM; + + sprintf(seg_name + strlen(fw_name) - 3, "b%02d", segment); + ret = request_firmware_into_buf(&seg_fw, seg_name, dev, + ptr, phdr->p_filesz); + if (ret) { + dev_err(dev, "error %zd loading %s\n", ret, seg_name); + kfree(seg_name); + return ret; + } + + if (seg_fw->size != phdr->p_filesz) { + dev_err(dev, + "failed to load segment %d from truncated file %s\n", + segment, seg_name); + ret = -EINVAL; + } + + release_firmware(seg_fw); + kfree(seg_name); + + return ret; +} + +/** + * qcom_mdt_get_size() - acquire size of the memory region needed to load mdt + * @fw: firmware object for the mdt file + * + * Returns size of the loaded firmware blob, or -EINVAL on failure. + */ +ssize_t qcom_mdt_get_size(const struct firmware *fw) +{ + const struct elf32_phdr *phdrs; + const struct elf32_phdr *phdr; + const struct elf32_hdr *ehdr; + phys_addr_t min_addr = PHYS_ADDR_MAX; + phys_addr_t max_addr = 0; + int i; + + ehdr = (struct elf32_hdr *)fw->data; + phdrs = (struct elf32_phdr *)(ehdr + 1); + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = &phdrs[i]; + + if (!mdt_phdr_valid(phdr)) + continue; + + if (phdr->p_paddr < min_addr) + min_addr = phdr->p_paddr; + + if (phdr->p_paddr + phdr->p_memsz > max_addr) + max_addr = ALIGN(phdr->p_paddr + phdr->p_memsz, SZ_4K); + } + + return min_addr < max_addr ? max_addr - min_addr : -EINVAL; +} +EXPORT_SYMBOL_GPL(qcom_mdt_get_size); + +/** + * qcom_mdt_read_metadata() - read header and metadata from mdt or mbn + * @fw: firmware of mdt header or mbn + * @data_len: length of the read metadata blob + * @fw_name: name of the firmware, for construction of segment file names + * @dev: device handle to associate resources with + * + * The mechanism that performs the authentication of the loading firmware + * expects an ELF header directly followed by the segment of hashes, with no + * padding inbetween. This function allocates a chunk of memory for this pair + * and copy the two pieces into the buffer. + * + * In the case of split firmware the hash is found directly following the ELF + * header, rather than at p_offset described by the second program header. + * + * The caller is responsible to free (kfree()) the returned pointer. + * + * Return: pointer to data, or ERR_PTR() + */ +void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len, + const char *fw_name, struct device *dev) +{ + const struct elf32_phdr *phdrs; + const struct elf32_hdr *ehdr; + unsigned int hash_segment = 0; + size_t hash_offset; + size_t hash_size; + size_t ehdr_size; + unsigned int i; + ssize_t ret; + void *data; + + ehdr = (struct elf32_hdr *)fw->data; + phdrs = (struct elf32_phdr *)(ehdr + 1); + + if (ehdr->e_phnum < 2) + return ERR_PTR(-EINVAL); + + if (phdrs[0].p_type == PT_LOAD) + return ERR_PTR(-EINVAL); + + for (i = 1; i < ehdr->e_phnum; i++) { + if ((phdrs[i].p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH) { + hash_segment = i; + break; + } + } + + if (!hash_segment) { + dev_err(dev, "no hash segment found in %s\n", fw_name); + return ERR_PTR(-EINVAL); + } + + ehdr_size = phdrs[0].p_filesz; + hash_size = phdrs[hash_segment].p_filesz; + + data = kmalloc(ehdr_size + hash_size, GFP_KERNEL); + if (!data) + return ERR_PTR(-ENOMEM); + + /* Copy ELF header */ + memcpy(data, fw->data, ehdr_size); + + if (ehdr_size + hash_size == fw->size) { + /* Firmware is split and hash is packed following the ELF header */ + hash_offset = phdrs[0].p_filesz; + memcpy(data + ehdr_size, fw->data + hash_offset, hash_size); + } else if (phdrs[hash_segment].p_offset + hash_size <= fw->size) { + /* Hash is in its own segment, but within the loaded file */ + hash_offset = phdrs[hash_segment].p_offset; + memcpy(data + ehdr_size, fw->data + hash_offset, hash_size); + } else { + /* Hash is in its own segment, beyond the loaded file */ + ret = mdt_load_split_segment(data + ehdr_size, phdrs, hash_segment, fw_name, dev); + if (ret) { + kfree(data); + return ERR_PTR(ret); + } + } + + *data_len = ehdr_size + hash_size; + + return data; +} +EXPORT_SYMBOL_GPL(qcom_mdt_read_metadata); + +/** + * qcom_mdt_pas_init() - initialize PAS region for firmware loading + * @dev: device handle to associate resources with + * @fw: firmware object for the mdt file + * @fw_name: name of the firmware, for construction of segment file names + * @pas_id: PAS identifier + * @mem_phys: physical address of allocated memory region + * @ctx: PAS metadata context, to be released by caller + * + * Returns 0 on success, negative errno otherwise. + */ +int qcom_mdt_pas_init(struct device *dev, const struct firmware *fw, + const char *fw_name, int pas_id, phys_addr_t mem_phys, + struct qcom_scm_pas_metadata *ctx) +{ + const struct elf32_phdr *phdrs; + const struct elf32_phdr *phdr; + const struct elf32_hdr *ehdr; + phys_addr_t min_addr = PHYS_ADDR_MAX; + phys_addr_t max_addr = 0; + bool relocate = false; + size_t metadata_len; + void *metadata; + int ret; + int i; + + ehdr = (struct elf32_hdr *)fw->data; + phdrs = (struct elf32_phdr *)(ehdr + 1); + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = &phdrs[i]; + + if (!mdt_phdr_valid(phdr)) + continue; + + if (phdr->p_flags & QCOM_MDT_RELOCATABLE) + relocate = true; + + if (phdr->p_paddr < min_addr) + min_addr = phdr->p_paddr; + + if (phdr->p_paddr + phdr->p_memsz > max_addr) + max_addr = ALIGN(phdr->p_paddr + phdr->p_memsz, SZ_4K); + } + + metadata = qcom_mdt_read_metadata(fw, &metadata_len, fw_name, dev); + if (IS_ERR(metadata)) { + ret = PTR_ERR(metadata); + dev_err(dev, "error %d reading firmware %s metadata\n", ret, fw_name); + goto out; + } + + ret = qcom_scm_pas_init_image(pas_id, metadata, metadata_len, ctx); + kfree(metadata); + if (ret) { + /* Invalid firmware metadata */ + dev_err(dev, "error %d initializing firmware %s\n", ret, fw_name); + goto out; + } + + if (relocate) { + ret = qcom_scm_pas_mem_setup(pas_id, mem_phys, max_addr - min_addr); + if (ret) { + /* Unable to set up relocation */ + dev_err(dev, "error %d setting up firmware %s\n", ret, fw_name); + goto out; + } + } + +out: + return ret; +} +EXPORT_SYMBOL_GPL(qcom_mdt_pas_init); + +static bool qcom_mdt_bins_are_split(const struct firmware *fw, const char *fw_name) +{ + const struct elf32_phdr *phdrs; + const struct elf32_hdr *ehdr; + uint64_t seg_start, seg_end; + int i; + + ehdr = (struct elf32_hdr *)fw->data; + phdrs = (struct elf32_phdr *)(ehdr + 1); + + for (i = 0; i < ehdr->e_phnum; i++) { + /* + * The size of the MDT file is not padded to include any + * zero-sized segments at the end. Ignore these, as they should + * not affect the decision about image being split or not. + */ + if (!phdrs[i].p_filesz) + continue; + + seg_start = phdrs[i].p_offset; + seg_end = phdrs[i].p_offset + phdrs[i].p_filesz; + if (seg_start > fw->size || seg_end > fw->size) + return true; + } + + return false; +} + +static int __qcom_mdt_load(struct device *dev, const struct firmware *fw, + const char *fw_name, int pas_id, void *mem_region, + phys_addr_t mem_phys, size_t mem_size, + phys_addr_t *reloc_base, bool pas_init) +{ + const struct elf32_phdr *phdrs; + const struct elf32_phdr *phdr; + const struct elf32_hdr *ehdr; + phys_addr_t mem_reloc; + phys_addr_t min_addr = PHYS_ADDR_MAX; + ssize_t offset; + bool relocate = false; + bool is_split; + void *ptr; + int ret = 0; + int i; + + if (!fw || !mem_region || !mem_phys || !mem_size) + return -EINVAL; + + is_split = qcom_mdt_bins_are_split(fw, fw_name); + ehdr = (struct elf32_hdr *)fw->data; + phdrs = (struct elf32_phdr *)(ehdr + 1); + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = &phdrs[i]; + + if (!mdt_phdr_valid(phdr)) + continue; + + if (phdr->p_flags & QCOM_MDT_RELOCATABLE) + relocate = true; + + if (phdr->p_paddr < min_addr) + min_addr = phdr->p_paddr; + } + + if (relocate) { + /* + * The image is relocatable, so offset each segment based on + * the lowest segment address. + */ + mem_reloc = min_addr; + } else { + /* + * Image is not relocatable, so offset each segment based on + * the allocated physical chunk of memory. + */ + mem_reloc = mem_phys; + } + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = &phdrs[i]; + + if (!mdt_phdr_valid(phdr)) + continue; + + offset = phdr->p_paddr - mem_reloc; + if (offset < 0 || offset + phdr->p_memsz > mem_size) { + dev_err(dev, "segment outside memory range\n"); + ret = -EINVAL; + break; + } + + if (phdr->p_filesz > phdr->p_memsz) { + dev_err(dev, + "refusing to load segment %d with p_filesz > p_memsz\n", + i); + ret = -EINVAL; + break; + } + + ptr = mem_region + offset; + + if (phdr->p_filesz && !is_split) { + /* Firmware is large enough to be non-split */ + if (phdr->p_offset + phdr->p_filesz > fw->size) { + dev_err(dev, "file %s segment %d would be truncated\n", + fw_name, i); + ret = -EINVAL; + break; + } + + memcpy(ptr, fw->data + phdr->p_offset, phdr->p_filesz); + } else if (phdr->p_filesz) { + /* Firmware not large enough, load split-out segments */ + ret = mdt_load_split_segment(ptr, phdrs, i, fw_name, dev); + if (ret) + break; + } + + if (phdr->p_memsz > phdr->p_filesz) + memset(ptr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz); + } + + if (reloc_base) + *reloc_base = mem_reloc; + + return ret; +} + +/** + * qcom_mdt_load() - load the firmware which header is loaded as fw + * @dev: device handle to associate resources with + * @fw: firmware object for the mdt file + * @firmware: name of the firmware, for construction of segment file names + * @pas_id: PAS identifier + * @mem_region: allocated memory region to load firmware into + * @mem_phys: physical address of allocated memory region + * @mem_size: size of the allocated memory region + * @reloc_base: adjusted physical address after relocation + * + * Returns 0 on success, negative errno otherwise. + */ +int qcom_mdt_load(struct device *dev, const struct firmware *fw, + const char *firmware, int pas_id, void *mem_region, + phys_addr_t mem_phys, size_t mem_size, + phys_addr_t *reloc_base) +{ + int ret; + + ret = qcom_mdt_pas_init(dev, fw, firmware, pas_id, mem_phys, NULL); + if (ret) + return ret; + + return __qcom_mdt_load(dev, fw, firmware, pas_id, mem_region, mem_phys, + mem_size, reloc_base, true); +} +EXPORT_SYMBOL_GPL(qcom_mdt_load); + +/** + * qcom_mdt_load_no_init() - load the firmware which header is loaded as fw + * @dev: device handle to associate resources with + * @fw: firmware object for the mdt file + * @firmware: name of the firmware, for construction of segment file names + * @pas_id: PAS identifier + * @mem_region: allocated memory region to load firmware into + * @mem_phys: physical address of allocated memory region + * @mem_size: size of the allocated memory region + * @reloc_base: adjusted physical address after relocation + * + * Returns 0 on success, negative errno otherwise. + */ +int qcom_mdt_load_no_init(struct device *dev, const struct firmware *fw, + const char *firmware, int pas_id, + void *mem_region, phys_addr_t mem_phys, + size_t mem_size, phys_addr_t *reloc_base) +{ + return __qcom_mdt_load(dev, fw, firmware, pas_id, mem_region, mem_phys, + mem_size, reloc_base, false); +} +EXPORT_SYMBOL_GPL(qcom_mdt_load_no_init); + +MODULE_DESCRIPTION("Firmware parser for Qualcomm MDT format"); +MODULE_LICENSE("GPL v2"); |