kapi/gdb: extend pretty printers

1 files changed, 63 insertions, 0 deletions

diff --git a/kapi/gdb/devices/resource.py b/kapi/gdb/devices/resource.py
new file mode 100644
index 00000000..dd5fd320
--- /dev/null
+++ b/kapi/gdb/devices/resource.py
@@ -0,0 +1,63 @@
+import gdb
+
+
+# Map from the resource_type enum integer value to a readable name.
+# kapi::devices::resource_type is a plain enum struct with no backing store
+# other than int, so we match by integer.
+_RESOURCE_TYPES = {
+    0: "mmio",
+    1: "port",
+    2: "irq",
+    3: "dma",
+}
+
+
+class KapiDevicesResourcePrinter(gdb.ValuePrinter):
+
+    def __init__(self, val):
+        self.__val = val
+        self.__type_int = int(val["type"])
+        self.__type_name = _RESOURCE_TYPES.get(self.__type_int, f"<unknown:{self.__type_int}>")
+
+    def _active_member(self):
+        union = self.__val["m_value"]
+        t = self.__type_int
+        if t == 0:
+            return union["range"]
+        if t == 1:
+            return union["port"]
+        if t == 2:
+            return union["irq"]
+        if t == 3:
+            return union["channel"]
+        return union
+
+    def to_string(self):
+        try:
+            t = self.__type_int
+            union = self.__val["m_value"]
+            if t == 0:  # mmio
+                start = int(union["range"]["start"]["m_value"])
+                size = int(union["range"]["size"]["value"])
+                return f"mmio [{start:#x}, +{size:#x})"
+            if t == 1:  # port
+                start = int(union["port"]["start"])
+                count = int(union["port"]["count"])
+                return f"port {start:#x}+{count}"
+            if t == 2:  # irq
+                number = int(union["irq"]["number"])
+                return f"irq {number}"
+            if t == 3:  # dma
+                number = int(union["channel"]["number"])
+                return f"dma channel {number}"
+        except (gdb.error, AttributeError):
+            pass
+        return f"resource ({self.__type_name})"
+
+    def children(self):
+        yield ("type", self.__val["type"])
+        yield (self.__type_name, self._active_member())
+
+    def display_hint(self):
+        return None
+