diff --git a/sw/device/lib/dif/dif_plic.h b/sw/device/lib/dif/dif_plic.h
index 0e6bff7..ae90c6f 100644
--- a/sw/device/lib/dif/dif_plic.h
+++ b/sw/device/lib/dif/dif_plic.h
@@ -7,7 +7,14 @@
 
 /**
  * @file
- * @brief <a href="/hw/ip/rv_plic/doc/">PLIC</a> Device Interface Functions
+ * @brief [PLIC](/hw/ip/rv_plic/doc/) Device Interface Functions.
+ *
+ * The PLIC should be largely compatible with the (currently draft) [RISC-V PLIC
+ * specification][plic], but tailored for the OpenTitan rv_plic register
+ * addresses. We intend to make the addresses compatible with the PLIC
+ * specification in the near future.
+ *
+ * [plic]: https://github.com/riscv/riscv-plic-spec/blob/master/riscv-plic.adoc
  */
 
 #include <stdbool.h>
@@ -192,8 +199,19 @@
  * Claims an IRQ and gets the information about the source.
  *
  * Claims an IRQ and returns the IRQ related data to the caller. This function
- * reads a target specific CC register. dif_plic_irq_complete must be called
- * after the claimed IRQ has been serviced.
+ * reads a target specific CC register. #dif_plic_irq_complete must be called in
+ * order to allow another interrupt with the same source id to be delivered.
+ * This usually would be done once the interrupt has been serviced.
+ *
+ * Another IRQ can be claimed before a prior IRQ is completed. In this way, this
+ * functionality is compatible with nested interrupt handling. The restriction
+ * is that you must Complete a Claimed IRQ before you will be able to claim an
+ * IRQ with the same ID. This allows a pair of Claim/Complete calls to be
+ * overlapped with another pair -- and there is no requirement that the
+ * interrupts should be Completed in the reverse order of when they were
+ * Claimed.
+ *
+ * @see #dif_plic_irq_complete
  *
  * @param plic PLIC state data.
  * @param target Target that claimed the IRQ.
@@ -210,7 +228,12 @@
  *
  * Finishes servicing of the claimed IRQ by writing the IRQ source ID back to a
  * target specific CC register. This function must be called after
- * dif_plic_claim_irq, when a caller has finished servicing the IRQ.
+ * #dif_plic_irq_claim, when the caller is prepared to service another IRQ with
+ * the same source ID. If a source ID is never Completed, then when future
+ * interrupts are Claimed, they will never have the source ID of the uncompleted
+ * IRQ.
+ *
+ * @see #dif_plic_irq_claim
  *
  * @param plic PLIC state data.
  * @param target Target that claimed the IRQ.
diff --git a/sw/device/lib/dif/dif_plic.md b/sw/device/lib/dif/dif_plic.md
index 8c48195..b2c9c42 100644
--- a/sw/device/lib/dif/dif_plic.md
+++ b/sw/device/lib/dif/dif_plic.md
@@ -25,7 +25,7 @@
 Type           | Item                        | Resolution  | Note/Collaterals
 ---------------|-----------------------------|-------------|------------------
 Implementation | [DIF_FEATURES][]            | Not Started |
-Coordination   | [DIF_HW_USAGE_REVIEWED][]   | Not Started |
+Coordination   | [DIF_HW_USAGE_REVIEWED][]   | Done        |
 Coordination   | [DIF_HW_FEATURE_COMPLETE][] | Not Started | [HW Dashboard]({{< relref "hw" >}})
 Implementation | [DIF_HW_PARAMS][]           | Not Started |
 Documentation  | [DIF_DOC_HW][]              | Not Started |
@@ -33,7 +33,7 @@
 Code Quality   | [DIF_CODE_STYLE][]          | Not Started |
 Coordination   | [DIF_DV_TESTS][]            | Not Started |
 Implementation | [DIF_USED_TOCK][]           | Not Started |
-Review         | HW IP Usage Reviewer(s)     | Not Started |
+Review         | HW IP Usage Reviewer(s)     | Not Started | @eunchan
 Review         | Reviewer(s)                 | Not Started |
 Review         | Signoff date                | Not Started |