- * Determine how many 1024b "DRAM lines" do we need to read from the
- * Sigma so we have a complete set of samples. Note that the last
- * line can be only partial, containing less than 64 clusters.
+ * Determine how many "DRAM lines" of 1024 bytes each we need to
+ * retrieve from the Sigma hardware, so that we have a complete
+ * set of samples. Note that the last line need not contain 64
+ * clusters, it might be partially filled only.
+ *
+ * When RMR_ROUND is set, the circular buffer in DRAM has wrapped
+ * around. Since the status of the very next line is uncertain in
+ * that case, we skip it and start reading from the next line. The
+ * circular buffer has 32K lines (0x8000).