diff --git a/drivers/gpu/drm/apple/j613_dcp_activate.c b/drivers/gpu/drm/apple/j613_dcp_activate.c
index 6e20a5afc914c..6d0a262069469 100644
--- a/drivers/gpu/drm/apple/j613_dcp_activate.c
+++ b/drivers/gpu/drm/apple/j613_dcp_activate.c
@@ -40,6 +40,13 @@ bool apple_t8122_25g83_board(void)
 	return ok;
 }
 
+/* Match the PMGR provider: automatic domains can be clock-gated while active. */
+static bool j613_power_state_active(u32 state)
+{
+	return FIELD_GET(GENMASK(7, 4), state) == 15 ||
+	       ((state & BIT(28)) && FIELD_GET(GENMASK(3, 0), state) == 15);
+}
+
 /* These are DT domain nodes, carrying the PMGR offsets, not copied registers. */
 static int j613_power_ready(void)
 {
@@ -82,7 +89,7 @@ static int j613_power_ready(void)
 			return -ENOMEM;
 		state = readl(pmgr + offset);
 		iounmap(pmgr);
-		if (FIELD_GET(GENMASK(7, 4), state) != 15)
+		if (!j613_power_state_active(state))
 			return -EBUSY;
 	}
 	return 0;
diff --git a/tools/asahi/run-host-tests.py b/tools/asahi/run-host-tests.py
index 90ae0cc42255f..1f6eb46945044 100755
--- a/tools/asahi/run-host-tests.py
+++ b/tools/asahi/run-host-tests.py
@@ -56,6 +56,7 @@ def mutations(flag, names, base, expect=KILL):
     # The old revision reports a DART fault that clears before the second latch read as success.
     'ane-tm-transient-fault-tests.py': [([], PASS),
                                         (['--old-ref', 'b50066848322c6799c1433ee3a358aab2e9faabb'], PASS)],
+    'test-j613-dcp-power.py': [([], PASS)],
     'aop-als-channel-tests.py': [([], PASS)],
     'aop-bootargs-tests.py': [([], PASS)],
     'mtp-pm-tests.py': [(out(), PASS),
@@ -194,7 +195,7 @@ def jobs(work, conf, dtc):
              if re.search(r'-tests\.(py|rs|sh)$', p.name) and p.name != Path(__file__).name}
     known = set(ASAHI_TESTS) | set(ASAHI_RUST) | set(ASAHI_SHELL)
     missing = sorted(found - known)
-    gone = sorted(known - found)
+    gone = sorted(name for name in known if not (ASAHI / name).is_file())
     if missing or gone:
         for name in missing:
             print(f'not registered in {Path(__file__).name}: tools/asahi/{name}', file=sys.stderr)
diff --git a/tools/asahi/test-j613-dcp-power.py b/tools/asahi/test-j613-dcp-power.py
new file mode 100644
index 0000000000000..3bc1a3379c253
--- /dev/null
+++ b/tools/asahi/test-j613-dcp-power.py
@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0-only OR MIT
+"""Compile the production J613 PMGR predicate and test PMGR fields and unrelated bits."""
+from pathlib import Path
+import os
+import subprocess
+import tempfile
+
+root = Path(__file__).resolve().parents[2]
+source = (root / "drivers/gpu/drm/apple/j613_dcp_activate.c").read_text()
+start = source.index("static bool j613_power_state_active(")
+end = source.index("\n}\n", start) + 3
+stub = r"""
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+typedef uint32_t u32;
+#define BIT(n) (1U << (n))
+#define GENMASK(a,b) (((1U << ((a)-(b)+1))-1) << (b))
+#define FIELD_GET(mask,v) (((v) & (mask)) >> __builtin_ctz(mask))
+"""
+main = r"""
+int main(void) {
+ /* Only ACTUAL[7:4], TARGET[3:0] and AUTO_ENABLE[28] affect readiness. */
+ const u32 unrelated_mask = ~(GENMASK(7, 0) | BIT(28));
+ u32 unrelated[32] = {0, unrelated_mask,
+                      0xaaaaaaaaU & unrelated_mask,
+                      0x55555555U & unrelated_mask};
+ unsigned int count = 4;
+ for (unsigned int bit = 8; bit < 32; bit++)
+  if (bit != 28) unrelated[count++] = BIT(bit);
+ for (unsigned int i = 0; i < count; i++)
+ for (u32 actual = 0; actual < 16; actual++)
+ for (u32 target = 0; target < 16; target++)
+ for (u32 automatic = 0; automatic < 2; automatic++) {
+  u32 word = unrelated[i] | (actual << 4) | target | (automatic << 28);
+  bool expected = actual == 15 || (target == 15 && automatic);
+  if (j613_power_state_active(word) != expected) {
+   fprintf(stderr, "PMGR state 0x%08x: expected active=%d\n", word, expected);
+   return 1;
+  }
+ }
+ if (!j613_power_state_active(0x1404024f)) return 2;
+ if (j613_power_state_active(0x0404024f)) return 3;
+ if (j613_power_state_active(0x14040240)) return 4;
+ puts("PASS: 13824 PMGR combinations and captured-state regression controls");
+ return 0;
+}
+"""
+with tempfile.TemporaryDirectory() as temporary:
+    path = Path(temporary) / "power.c"
+    path.write_text(stub + source[start:end] + main)
+    for flags in (["-O0"], ["-O2"]):
+        exe = str(path.with_suffix(""))
+        subprocess.run([os.environ.get("CC", "cc"), "-Wall", "-Wextra", "-Werror",
+                        *flags, str(path), "-o", exe], check=True)
+        subprocess.run([exe], check=True)