1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Qualcomm Peripheral Image Loader
  4 *
  5 * Copyright (C) 2016 Linaro Ltd
  6 * Copyright (C) 2015 Sony Mobile Communications Inc
  7 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
  8 */
  9
 10#include <linux/device.h>
 11#include <linux/elf.h>
 12#include <linux/firmware.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/qcom_scm.h>
 16#include <linux/sizes.h>
 17#include <linux/slab.h>
 18#include <linux/soc/qcom/mdt_loader.h>
 19
 20static bool mdt_phdr_valid(const struct elf32_phdr *phdr)
 21{
 22	if (phdr->p_type != PT_LOAD)
 23		return false;
 24
 25	if ((phdr->p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH)
 26		return false;
 27
 28	if (!phdr->p_memsz)
 29		return false;
 30
 31	return true;
 32}
 33
 34/**
 35 * qcom_mdt_get_size() - acquire size of the memory region needed to load mdt
 36 * @fw:		firmware object for the mdt file
 37 *
 38 * Returns size of the loaded firmware blob, or -EINVAL on failure.
 39 */
 40ssize_t qcom_mdt_get_size(const struct firmware *fw)
 41{
 42	const struct elf32_phdr *phdrs;
 43	const struct elf32_phdr *phdr;
 44	const struct elf32_hdr *ehdr;
 45	phys_addr_t min_addr = PHYS_ADDR_MAX;
 46	phys_addr_t max_addr = 0;
 47	int i;
 48
 49	ehdr = (struct elf32_hdr *)fw->data;
 50	phdrs = (struct elf32_phdr *)(ehdr + 1);
 51
 52	for (i = 0; i < ehdr->e_phnum; i++) {
 53		phdr = &phdrs[i];
 54
 55		if (!mdt_phdr_valid(phdr))
 56			continue;
 57
 58		if (phdr->p_paddr < min_addr)
 59			min_addr = phdr->p_paddr;
 60
 61		if (phdr->p_paddr + phdr->p_memsz > max_addr)
 62			max_addr = ALIGN(phdr->p_paddr + phdr->p_memsz, SZ_4K);
 63	}
 64
 65	return min_addr < max_addr ? max_addr - min_addr : -EINVAL;
 66}
 67EXPORT_SYMBOL_GPL(qcom_mdt_get_size);
 68
 69/**
 70 * qcom_mdt_read_metadata() - read header and metadata from mdt or mbn
 71 * @fw:		firmware of mdt header or mbn
 72 * @data_len:	length of the read metadata blob
 73 *
 74 * The mechanism that performs the authentication of the loading firmware
 75 * expects an ELF header directly followed by the segment of hashes, with no
 76 * padding inbetween. This function allocates a chunk of memory for this pair
 77 * and copy the two pieces into the buffer.
 78 *
 79 * In the case of split firmware the hash is found directly following the ELF
 80 * header, rather than at p_offset described by the second program header.
 81 *
 82 * The caller is responsible to free (kfree()) the returned pointer.
 83 *
 84 * Return: pointer to data, or ERR_PTR()
 85 */
 86void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len)
 87{
 88	const struct elf32_phdr *phdrs;
 89	const struct elf32_hdr *ehdr;
 90	size_t hash_offset;
 91	size_t hash_size;
 92	size_t ehdr_size;
 93	void *data;
 94
 95	ehdr = (struct elf32_hdr *)fw->data;
 96	phdrs = (struct elf32_phdr *)(ehdr + 1);
 97
 98	if (ehdr->e_phnum < 2)
 99		return ERR_PTR(-EINVAL);
100
101	if (phdrs[0].p_type == PT_LOAD || phdrs[1].p_type == PT_LOAD)
102		return ERR_PTR(-EINVAL);
103
104	if ((phdrs[1].p_flags & QCOM_MDT_TYPE_MASK) != QCOM_MDT_TYPE_HASH)
105		return ERR_PTR(-EINVAL);
106
107	ehdr_size = phdrs[0].p_filesz;
108	hash_size = phdrs[1].p_filesz;
109
110	data = kmalloc(ehdr_size + hash_size, GFP_KERNEL);
111	if (!data)
112		return ERR_PTR(-ENOMEM);
113
114	/* Is the header and hash already packed */
115	if (ehdr_size + hash_size == fw->size)
116		hash_offset = phdrs[0].p_filesz;
117	else
118		hash_offset = phdrs[1].p_offset;
119
120	memcpy(data, fw->data, ehdr_size);
121	memcpy(data + ehdr_size, fw->data + hash_offset, hash_size);
122
123	*data_len = ehdr_size + hash_size;
124
125	return data;
126}
127EXPORT_SYMBOL_GPL(qcom_mdt_read_metadata);
128
129static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
130			   const char *firmware, int pas_id, void *mem_region,
131			   phys_addr_t mem_phys, size_t mem_size,
132			   phys_addr_t *reloc_base, bool pas_init)
133{
134	const struct elf32_phdr *phdrs;
135	const struct elf32_phdr *phdr;
136	const struct elf32_hdr *ehdr;
137	const struct firmware *seg_fw;
138	phys_addr_t mem_reloc;
139	phys_addr_t min_addr = PHYS_ADDR_MAX;
140	phys_addr_t max_addr = 0;
141	size_t metadata_len;
142	size_t fw_name_len;
143	ssize_t offset;
144	void *metadata;
145	char *fw_name;
146	bool relocate = false;
147	void *ptr;
148	int ret = 0;
149	int i;
150
151	if (!fw || !mem_region || !mem_phys || !mem_size)
152		return -EINVAL;
153
154	ehdr = (struct elf32_hdr *)fw->data;
155	phdrs = (struct elf32_phdr *)(ehdr + 1);
156
157	fw_name_len = strlen(firmware);
158	if (fw_name_len <= 4)
159		return -EINVAL;
160
161	fw_name = kstrdup(firmware, GFP_KERNEL);
162	if (!fw_name)
163		return -ENOMEM;
164
165	if (pas_init) {
166		metadata = qcom_mdt_read_metadata(fw, &metadata_len);
167		if (IS_ERR(metadata)) {
168			ret = PTR_ERR(metadata);
169			goto out;
170		}
171
172		ret = qcom_scm_pas_init_image(pas_id, metadata, metadata_len);
173
174		kfree(metadata);
175		if (ret) {
176			dev_err(dev, "invalid firmware metadata\n");
177			goto out;
178		}
179	}
180
181	for (i = 0; i < ehdr->e_phnum; i++) {
182		phdr = &phdrs[i];
183
184		if (!mdt_phdr_valid(phdr))
185			continue;
186
187		if (phdr->p_flags & QCOM_MDT_RELOCATABLE)
188			relocate = true;
189
190		if (phdr->p_paddr < min_addr)
191			min_addr = phdr->p_paddr;
192
193		if (phdr->p_paddr + phdr->p_memsz > max_addr)
194			max_addr = ALIGN(phdr->p_paddr + phdr->p_memsz, SZ_4K);
195	}
196
197	if (relocate) {
198		if (pas_init) {
199			ret = qcom_scm_pas_mem_setup(pas_id, mem_phys,
200						     max_addr - min_addr);
201			if (ret) {
202				dev_err(dev, "unable to setup relocation\n");
203				goto out;
204			}
205		}
206
207		/*
208		 * The image is relocatable, so offset each segment based on
209		 * the lowest segment address.
210		 */
211		mem_reloc = min_addr;
212	} else {
213		/*
214		 * Image is not relocatable, so offset each segment based on
215		 * the allocated physical chunk of memory.
216		 */
217		mem_reloc = mem_phys;
218	}
219
220	for (i = 0; i < ehdr->e_phnum; i++) {
221		phdr = &phdrs[i];
222
223		if (!mdt_phdr_valid(phdr))
224			continue;
225
226		offset = phdr->p_paddr - mem_reloc;
227		if (offset < 0 || offset + phdr->p_memsz > mem_size) {
228			dev_err(dev, "segment outside memory range\n");
229			ret = -EINVAL;
230			break;
231		}
232
233		ptr = mem_region + offset;
234
235		if (phdr->p_filesz && phdr->p_offset < fw->size) {
236			/* Firmware is large enough to be non-split */
237			if (phdr->p_offset + phdr->p_filesz > fw->size) {
238				dev_err(dev,
239					"failed to load segment %d from truncated file %s\n",
240					i, firmware);
241				ret = -EINVAL;
242				break;
243			}
244
245			memcpy(ptr, fw->data + phdr->p_offset, phdr->p_filesz);
246		} else if (phdr->p_filesz) {
247			/* Firmware not large enough, load split-out segments */
248			sprintf(fw_name + fw_name_len - 3, "b%02d", i);
249			ret = request_firmware_into_buf(&seg_fw, fw_name, dev,
250							ptr, phdr->p_filesz);
251			if (ret) {
252				dev_err(dev, "failed to load %s\n", fw_name);
253				break;
254			}
255
256			release_firmware(seg_fw);
257		}
258
259		if (phdr->p_memsz > phdr->p_filesz)
260			memset(ptr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
261	}
262
263	if (reloc_base)
264		*reloc_base = mem_reloc;
265
266out:
267	kfree(fw_name);
268
269	return ret;
270}
271
272/**
273 * qcom_mdt_load() - load the firmware which header is loaded as fw
274 * @dev:	device handle to associate resources with
275 * @fw:		firmware object for the mdt file
276 * @firmware:	name of the firmware, for construction of segment file names
277 * @pas_id:	PAS identifier
278 * @mem_region:	allocated memory region to load firmware into
279 * @mem_phys:	physical address of allocated memory region
280 * @mem_size:	size of the allocated memory region
281 * @reloc_base:	adjusted physical address after relocation
282 *
283 * Returns 0 on success, negative errno otherwise.
284 */
285int qcom_mdt_load(struct device *dev, const struct firmware *fw,
286		  const char *firmware, int pas_id, void *mem_region,
287		  phys_addr_t mem_phys, size_t mem_size,
288		  phys_addr_t *reloc_base)
289{
290	return __qcom_mdt_load(dev, fw, firmware, pas_id, mem_region, mem_phys,
291			       mem_size, reloc_base, true);
292}
293EXPORT_SYMBOL_GPL(qcom_mdt_load);
294
295/**
296 * qcom_mdt_load_no_init() - load the firmware which header is loaded as fw
297 * @dev:	device handle to associate resources with
298 * @fw:		firmware object for the mdt file
299 * @firmware:	name of the firmware, for construction of segment file names
300 * @pas_id:	PAS identifier
301 * @mem_region:	allocated memory region to load firmware into
302 * @mem_phys:	physical address of allocated memory region
303 * @mem_size:	size of the allocated memory region
304 * @reloc_base:	adjusted physical address after relocation
305 *
306 * Returns 0 on success, negative errno otherwise.
307 */
308int qcom_mdt_load_no_init(struct device *dev, const struct firmware *fw,
309			  const char *firmware, int pas_id,
310			  void *mem_region, phys_addr_t mem_phys,
311			  size_t mem_size, phys_addr_t *reloc_base)
312{
313	return __qcom_mdt_load(dev, fw, firmware, pas_id, mem_region, mem_phys,
314			       mem_size, reloc_base, false);
315}
316EXPORT_SYMBOL_GPL(qcom_mdt_load_no_init);
317
318MODULE_DESCRIPTION("Firmware parser for Qualcomm MDT format");
319MODULE_LICENSE("GPL v2");