[dif/pattgen] Add DIF checklist

This adds a DIF checklist for the pattgen IP and updates it to reflect
the current state of the SW. This addresses a task in #10504.

Signed-off-by: Timothy Trippel <ttrippel@google.com>
diff --git a/hw/ip/pattgen/data/pattgen.prj.hjson b/hw/ip/pattgen/data/pattgen.prj.hjson
index ec7b1fa..2fa8a64 100644
--- a/hw/ip/pattgen/data/pattgen.prj.hjson
+++ b/hw/ip/pattgen/data/pattgen.prj.hjson
@@ -7,6 +7,7 @@
     design_spec:        "../doc",
     dv_doc:             "../doc/dv",
     hw_checklist:       "../doc/checklist",
+    sw_checklist:       "/sw/device/lib/dif/dif_pattgen",
     revisions: [
       {
         version:            "1.0",
diff --git a/sw/device/lib/dif/dif_pattgen.md b/sw/device/lib/dif/dif_pattgen.md
new file mode 100644
index 0000000..bc6ec0b
--- /dev/null
+++ b/sw/device/lib/dif/dif_pattgen.md
@@ -0,0 +1,52 @@
+---
+title: "Pattern Generator DIF Checklist"
+---
+
+This checklist is for [Development Stage]({{< relref "/doc/project/development_stages.md" >}}) transitions for the [Pattern Generator DIF]({{< relref "hw/ip/pattgen/doc" >}}).
+All checklist items refer to the content in the [Checklist]({{< relref "/doc/project/checklist.md" >}}).
+
+<h2>DIF Checklist</h2>
+
+<h3>S1</h3>
+
+Type           | Item                 | Resolution  | Note/Collaterals
+---------------|----------------------|-------------|------------------
+Implementation | [DIF_EXISTS][]       | Done        |
+Implementation | [DIF_USED_IN_TREE][] | Done        |
+Tests          | [DIF_TEST_SMOKE][]   | Not Started |
+
+[DIF_EXISTS]:       {{< relref "/doc/project/checklist.md#dif_exists" >}}
+[DIF_USED_IN_TREE]: {{< relref "/doc/project/checklist.md#dif_used_in_tree" >}}
+[DIF_TEST_SMOKE]:   {{< relref "/doc/project/checklist.md#dif_test_smoke" >}}
+
+<h3>S2</h3>
+
+Type           | Item                        | Resolution  | Note/Collaterals
+---------------|-----------------------------|-------------|------------------
+Coordination   | [DIF_HW_FEATURE_COMPLETE][] | Done        | [HW Dashboard]({{< relref "hw" >}})
+Implementation | [DIF_FEATURES][]            | In Progress |
+Coordination   | [DIF_DV_TESTS][]            | Not Started |
+
+[DIF_HW_FEATURE_COMPLETE]: {{< relref "/doc/project/checklist.md#dif_hw_feature_complete" >}}
+[DIF_FEATURES]:            {{< relref "/doc/project/checklist.md#dif_features" >}}
+[DIF_DV_TESTS]:            {{< relref "/doc/project/checklist.md#dif_dv_tests" >}}
+
+<h3>S3</h3>
+
+Type           | Item                             | Resolution  | Note/Collaterals
+---------------|----------------------------------|-------------|------------------
+Coordination   | [DIF_HW_DESIGN_COMPLETE][]       | Not Started |
+Coordination   | [DIF_HW_VERIFICATION_COMPLETE][] | Not Started |
+Documentation  | [DIF_DOC_HW][]                   | Not Started |
+Code Quality   | [DIF_CODE_STYLE][]               | Not Started |
+Tests          | [DIF_TEST_UNIT][]                | Not Started |
+Review         | [DIF_TODO_COMPLETE][]            | Not Started |
+Review         | Reviewer(s)                      | Not Started |
+Review         | Signoff date                     | Not Started |
+
+[DIF_HW_DESIGN_COMPLETE]:       {{< relref "/doc/project/checklist.md#dif_hw_design_complete" >}}
+[DIF_HW_VERIFICATION_COMPLETE]: {{< relref "/doc/project/checklist.md#dif_hw_verification_complete" >}}
+[DIF_DOC_HW]:                   {{< relref "/doc/project/checklist.md#dif_doc_hw" >}}
+[DIF_CODE_STYLE]:               {{< relref "/doc/project/checklist.md#dif_code_style" >}}
+[DIF_TEST_UNIT]:                {{< relref "/doc/project/checklist.md#dif_test_unit" >}}
+[DIF_TODO_COMPLETE]:            {{< relref "/doc/project/checklist.md#dif_todo_complete" >}}