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-rw-r--r--flash.h24
1 files changed, 14 insertions, 10 deletions
diff --git a/flash.h b/flash.h
index f73f12e..6ff691a 100644
--- a/flash.h
+++ b/flash.h
@@ -59,18 +59,22 @@ enum chipbustype {
};
/*
- * The following write granularities are known:
- * - 1 bit: Each bit can be cleared individually.
- * - 1 byte: A byte can be written once. Further writes to an already written byte cause its contents to be
- * either undefined or to stay unchanged.
- * - 128 bytes: If less than 128 bytes are written, the rest will be erased. Each write to a 128-byte region
- * will trigger an automatic erase before anything is written. Very uncommon behaviour.
- * - 256 bytes: If less than 256 bytes are written, the contents of the unwritten bytes are undefined.
+ * The following enum defines possible write granularities of flash chips. These tend to reflect the properties
+ * of the actual hardware not necesserily the write function(s) defined by the respective struct flashchip.
+ * The latter might (and should) be more precisely specified, e.g. they might bail out early if their execution
+ * would result in undefined chip contents.
*/
enum write_granularity {
- write_gran_256bytes = 0, /* We assume 256 byte granularity by default. */
- write_gran_1bit,
- write_gran_1byte,
+ /* We assume 256 byte granularity by default. */
+ write_gran_256bytes = 0,/* If less than 256 bytes are written, the unwritten bytes are undefined. */
+ write_gran_1bit, /* Each bit can be cleared individually. */
+ write_gran_1byte, /* A byte can be written once. Further writes to an already written byte cause
+ * its contents to be either undefined or to stay unchanged. */
+ write_gran_264bytes, /* If less than 264 bytes are written, the unwritten bytes are undefined. */
+ write_gran_512bytes, /* If less than 512 bytes are written, the unwritten bytes are undefined. */
+ write_gran_528bytes, /* If less than 528 bytes are written, the unwritten bytes are undefined. */
+ write_gran_1024bytes, /* If less than 1024 bytes are written, the unwritten bytes are undefined. */
+ write_gran_1056bytes, /* If less than 1056 bytes are written, the unwritten bytes are undefined. */
};
/*
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