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| -rw-r--r-- | src/target/target.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/target/target.h b/src/target/target.h index 0f8be6f2..19d8013a 100644 --- a/src/target/target.h +++ b/src/target/target.h @@ -363,6 +363,30 @@ extern int target_write_memory(struct target_s *target, extern int target_bulk_write_memory(struct target_s *target, uint32_t address, uint32_t count, uint8_t *buffer); +/* + * Write to target memory using the virtual address. + * + * Note that this fn is used to implement software breakpoints. Targets + * can implement support for software breakpoints to memory marked as read + * only by making this fn write to ram even if it is read only(MMU or + * MPUs). + * + * It is sufficient to implement for writing a single word(16 or 32 in + * ARM32/16 bit case) to write the breakpoint to ram. + * + * The target should also take care of "other things" to make sure that + * software breakpoints can be written using this function. E.g. + * when there is a separate instruction and data cache, this fn must + * make sure that the instruction cache is synced up to the potential + * code change that can happen as a result of the memory write(typically + * by invalidating the cache). + * + * The high level wrapper fn in target.c will break down this memory write + * request to multiple write requests to the target driver to e.g. guarantee + * that writing 4 bytes to an aligned address happens with a single 32 bit + * write operation, thus making this fn suitable to e.g. write to special + * peripheral registers which do not support byte operations. + */ extern int target_write_buffer(struct target_s *target, uint32_t address, uint32_t size, uint8_t *buffer); extern int target_read_buffer(struct target_s *target, uint32_t address, uint32_t size, uint8_t *buffer); extern int target_checksum_memory(struct target_s *target, uint32_t address, uint32_t size, uint32_t* crc); |