From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- include/linux/ihex.h | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 include/linux/ihex.h (limited to 'include/linux/ihex.h') diff --git a/include/linux/ihex.h b/include/linux/ihex.h new file mode 100644 index 000000000..86713b058 --- /dev/null +++ b/include/linux/ihex.h @@ -0,0 +1,89 @@ +/* + * 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 +#include +#include + +/* 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 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 *rec; + size_t ofs = 0; + + while (ofs <= fw->size - sizeof(*rec)) { + rec = (void *)&fw->data[ofs]; + + /* Zero length marks end of records */ + if (!be16_to_cpu(rec->len)) + return 0; + + /* Point to next record... */ + ofs += (sizeof(*rec) + be16_to_cpu(rec->len) + 3) & ~3; + } + 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; +} +#ifndef _LINUX_LIBRE_IHEX_H +#define _LINUX_LIBRE_IHEX_H + +static inline int +maybe_reject_ihex_firmware(const struct firmware **fw, + const char *name, struct device *device) +{ + if (strstr (name, NONFREE_FIRMWARE)) + return reject_firmware(fw, name, device); + else + return request_ihex_firmware(fw, name, device); +} + +#endif /* _LINUX_LIBRE_IHEX_H */ + +#endif /* __LINUX_IHEX_H__ */ -- cgit v1.2.3