[linux-block.git] / include / linux / ihex.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Compact binary representation of ihex records. Some devices need their
 * firmware loaded in strange orders rather than a single big blob, but
 * actually parsing ihex-as-text within the kernel seems silly. Thus,...
 */

#ifndef __LINUX_IHEX_H__
#define __LINUX_IHEX_H__

#include <linux/types.h>
#include <linux/firmware.h>
#include <linux/device.h>

/* Intel HEX files actually limit the length to 256 bytes, but we have
   drivers which would benefit from using separate records which are
   longer than that, so we extend to 16 bits of length */
struct ihex_binrec {
	__be32 addr;
	__be16 len;
	uint8_t data[0];
} __attribute__((packed));

/* Find the next record, taking into account the 4-byte alignment */
static inline const struct ihex_binrec *
__ihex_next_binrec(const struct ihex_binrec *rec)
{
	int next = ((be16_to_cpu(rec->len) + 5) & ~3) - 2;
	rec = (void *)&rec->data[next];

	return rec;
}

static inline const struct ihex_binrec *
ihex_next_binrec(const struct ihex_binrec *rec)
{
	rec = __ihex_next_binrec(rec);

	return be16_to_cpu(rec->len) ? rec : NULL;
}

/* Check that ihex_next_binrec() won't take us off the end of the image... */
static inline int ihex_validate_fw(const struct firmware *fw)
{
	const struct ihex_binrec *end, *rec;

	rec = (const void *)fw->data;
	end = (const void *)&fw->data[fw->size - sizeof(*end)];

	for (; rec <= end; rec = __ihex_next_binrec(rec)) {
		/* Zero length marks end of records */
		if (!be16_to_cpu(rec->len))
			return 0;
	}
	return -EINVAL;
}

/* Request firmware and validate it so that we can trust we won't
 * run off the end while reading records... */
static inline int request_ihex_firmware(const struct firmware **fw,
					const char *fw_name,
					struct device *dev)
{
	const struct firmware *lfw;
	int ret;

	ret = request_firmware(&lfw, fw_name, dev);
	if (ret)
		return ret;
	ret = ihex_validate_fw(lfw);
	if (ret) {
		dev_err(dev, "Firmware \"%s\" not valid IHEX records\n",
			fw_name);
		release_firmware(lfw);
		return ret;
	}
	*fw = lfw;
	return 0;
}
#endif /* __LINUX_IHEX_H__ */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
bacfe09d DW	2	/*
	3	* Compact binary representation of ihex records. Some devices need their
	4	* firmware loaded in strange orders rather than a single big blob, but
	5	* actually parsing ihex-as-text within the kernel seems silly. Thus,...
	6	*/
	7
	8	#ifndef __LINUX_IHEX_H__
	9	#define __LINUX_IHEX_H__
	10
	11	#include <linux/types.h>
	12	#include <linux/firmware.h>
f1485f3d	13	#include <linux/device.h>
bacfe09d DW	14
	15	/* Intel HEX files actually limit the length to 256 bytes, but we have
	16	drivers which would benefit from using separate records which are
	17	longer than that, so we extend to 16 bits of length */
	18	struct ihex_binrec {
	19	__be32 addr;
	20	__be16 len;
	21	uint8_t data[0];
85ebd003	22	} __attribute__((packed));
bacfe09d DW	23
	24	/* Find the next record, taking into account the 4-byte alignment */
	25	static inline const struct ihex_binrec *
8092e792	26	__ihex_next_binrec(const struct ihex_binrec *rec)
bacfe09d DW	27	{
	28	int next = ((be16_to_cpu(rec->len) + 5) & ~3) - 2;
	29	rec = (void *)&rec->data[next];
	30
8092e792 AS	31	return rec;
	32	}
	33
	34	static inline const struct ihex_binrec *
	35	ihex_next_binrec(const struct ihex_binrec *rec)
	36	{
	37	rec = __ihex_next_binrec(rec);
	38
bacfe09d DW	39	return be16_to_cpu(rec->len) ? rec : NULL;
	40	}
	41
	42	/* Check that ihex_next_binrec() won't take us off the end of the image... */
	43	static inline int ihex_validate_fw(const struct firmware *fw)
	44	{
8092e792	45	const struct ihex_binrec end, rec;
bacfe09d	46
8092e792 AS	47	rec = (const void *)fw->data;
8092e792 AS	48	end = (const void )&fw->data[fw->size - sizeof(end)];
bacfe09d	49
8092e792	50	for (; rec <= end; rec = __ihex_next_binrec(rec)) {
bacfe09d DW	51	/* Zero length marks end of records */
	52	if (!be16_to_cpu(rec->len))
	53	return 0;
bacfe09d DW	54	}
	55	return -EINVAL;
	56	}
f1485f3d DW	57
	58	/* Request firmware and validate it so that we can trust we won't
	59	* run off the end while reading records... */
	60	static inline int request_ihex_firmware(const struct firmware **fw,
	61	const char *fw_name,
	62	struct device *dev)
	63	{
	64	const struct firmware *lfw;
	65	int ret;
	66
	67	ret = request_firmware(&lfw, fw_name, dev);
	68	if (ret)
	69	return ret;
	70	ret = ihex_validate_fw(lfw);
	71	if (ret) {
	72	dev_err(dev, "Firmware \"%s\" not valid IHEX records\n",
	73	fw_name);
	74	release_firmware(lfw);
	75	return ret;
	76	}
	77	*fw = lfw;
	78	return 0;
	79	}
bacfe09d	80	#endif /* __LINUX_IHEX_H__ */