diff --git a/drivers/gpu/drm/asahi/g15/hw.rs b/drivers/gpu/drm/asahi/g15/hw.rs
index df8feb36470fb7..582b0d96ff2a09 100644
--- a/drivers/gpu/drm/asahi/g15/hw.rs
+++ b/drivers/gpu/drm/asahi/g15/hw.rs
@@ -196,6 +196,54 @@ pub(crate) mod t6030 {
                 0x54, 0xf9, 0xf0, 0x6e, 0x0a, 0x61, 0x36, 0x3e,
             ],
           },
+          // Some J516S units on the same 14.7 boot chain load a different B0
+          // TEXT image with identical sizes and marker. Pin its complete
+          // measured digest for the J516S only.
+          FirmwareBuild {
+            name: "J516S cd05 firmware (14.7 boot chain)",
+            machine: Some(kernel::c_str!("apple,j516s")),
+            text_size: 0x5c000,
+            data_size: 0x114000,
+            marker: 0x58e88,
+            text_sha256: [
+                0xcd, 0x05, 0xaf, 0x6a, 0x82, 0x8b, 0x52, 0xe4,
+                0xc2, 0xfe, 0xd2, 0x00, 0x86, 0xd3, 0xd1, 0x8a,
+                0x7d, 0xb4, 0x2e, 0x03, 0xa8, 0xfd, 0x6f, 0x83,
+                0x54, 0xf9, 0xf0, 0x6e, 0x0a, 0x61, 0x36, 0x3e,
+            ],
+          },
+          // J514S (14-inch) firmware measured on the 14.7 boot chain with
+          // system firmware 26.6.2; the GPU reached READY with the bring-up
+          // prefix override (issue #247).
+          FirmwareBuild {
+            name: "J514S 4118 firmware (14.7 boot chain)",
+            machine: Some(kernel::c_str!("apple,j514s")),
+            text_size: 0x5c000,
+            data_size: 0x114000,
+            marker: 0x58e88,
+            text_sha256: [
+                0x41, 0x18, 0x33, 0xa7, 0xde, 0xd7, 0x73, 0xfe,
+                0xea, 0xc4, 0xa1, 0x81, 0x55, 0x2e, 0x3f, 0xf5,
+                0x58, 0x2e, 0xaf, 0x44, 0x35, 0xf2, 0xdd, 0x8f,
+                0x62, 0x0c, 0x1e, 0xd0, 0xb3, 0x1d, 0xf1, 0xb0,
+            ],
+          },
+          // J516S (16-inch) firmware measured on the 14.7 boot chain with
+          // system firmware 26.6.2; the GPU reached READY with the bring-up
+          // prefix override (issue #247).
+          FirmwareBuild {
+            name: "J516S 4118 firmware (14.7 boot chain)",
+            machine: Some(kernel::c_str!("apple,j516s")),
+            text_size: 0x5c000,
+            data_size: 0x114000,
+            marker: 0x58e88,
+            text_sha256: [
+                0x41, 0x18, 0x33, 0xa7, 0xde, 0xd7, 0x73, 0xfe,
+                0xea, 0xc4, 0xa1, 0x81, 0x55, 0x2e, 0x3f, 0xf5,
+                0x58, 0x2e, 0xaf, 0x44, 0x35, 0xf2, 0xdd, 0x8f,
+                0x62, 0x0c, 0x1e, 0xd0, 0xb3, 0x1d, 0xf1, 0xb0,
+            ],
+          },
         ],
         machine: kernel::c_str!("apple,t6030"),
         platform: super::Platform::AdtWithPmp,
diff --git a/tools/asahi/g15-maintained-handoff-tests.py b/tools/asahi/g15-maintained-handoff-tests.py
index e0fb4438de3793..738facb331e521 100644
--- a/tools/asahi/g15-maintained-handoff-tests.py
+++ b/tools/asahi/g15-maintained-handoff-tests.py
@@ -137,12 +137,15 @@ def item(s, marker):
         OWNER_CALLS.set(0); let bytes = fixture(kind);
         assert!(parse(&dev, &Adt { data: &bytes }).is_err()); assert_eq!(OWNER_CALLS.get(), 0);
     }
-    assert_eq!(BUILDS.len(), 4, "maintained B0 firmware row must not require an absent profile symbol");
+    assert_eq!(BUILDS.len(), 7, "maintained B0 firmware row must not require an absent profile symbol");
     for (row, machine) in [(1, &b"apple,j516s"[..]), (2, &b"apple,j514s"[..])] {
         assert_eq!(BUILDS[row].machine.unwrap().to_bytes(), machine);
         assert_eq!((BUILDS[row].text_size, BUILDS[row].data_size, BUILDS[row].marker), (0x5c000, 0x114000, 0x58e88));
         assert_eq!(BUILDS[row].text_sha256, [0xda,0x26,0xec,0xca,0xb1,0xf8,0x59,0x8d,0xa8,0x0c,0x85,0x5e,0xca,0x91,0x65,0x20,0x40,0x6d,0x1d,0x06,0x70,0xf1,0xd4,0x70,0xe7,0x9b,0xb9,0xb0,0x22,0x09,0xdb,0x53]);
     }
+    assert_eq!(BUILDS[4].machine.unwrap().to_bytes(), b"apple,j516s");
+    assert_eq!((BUILDS[4].text_size, BUILDS[4].data_size, BUILDS[4].marker), (0x5c000, 0x114000, 0x58e88));
+    assert_eq!(BUILDS[4].text_sha256, [0xcd,0x05,0xaf,0x6a,0x82,0x8b,0x52,0xe4,0xc2,0xfe,0xd2,0x00,0x86,0xd3,0xd1,0x8a,0x7d,0xb4,0x2e,0x03,0xa8,0xfd,0x6f,0x83,0x54,0xf9,0xf0,0x6e,0x0a,0x61,0x36,0x3e]);
     // Issue #247: this J514S build must pin without the bring-up override.
     use identity::lookup::{Measured, Verdict, verdict};
     let measured = Measured {
@@ -157,9 +160,9 @@ def item(s, marker):
                    marker: b.marker, sha256: b.text_sha256 },
         b.machine.map_or(true, |board| board.to_bytes() == machine),
     )), 0);
-    assert!(matches!(identify(&measured, b"apple,j514s"), Verdict::Pinned(_)),
+    assert!(matches!(identify(&measured, b"apple,j514s"), Verdict::Pinned(3)),
             "J514S cd05 firmware must pin without a prefix override");
-    assert_eq!(identify(&measured, b"apple,j516s"), Verdict::Refused);
+    assert_eq!(identify(&measured, b"apple,j516s"), Verdict::Pinned(4));
     let mut changed = measured;
     changed.sha256[31] ^= 1;
     assert_eq!(identify(&changed, b"apple,j514s"), Verdict::Refused);
@@ -169,6 +172,36 @@ def item(s, marker):
     assert_eq!(identify(&changed, b"apple,j514s"), Verdict::Refused);
     changed = measured; changed.marker += 8;
     assert_eq!(identify(&changed, b"apple,j514s"), Verdict::Refused);
+    // Issue #247: the 4118 build pins on the J514S and the J516S, each to
+    // its own row, without the bring-up override.
+    let digest = [0x41,0x18,0x33,0xa7,0xde,0xd7,0x73,0xfe,
+                  0xea,0xc4,0xa1,0x81,0x55,0x2e,0x3f,0xf5,
+                  0x58,0x2e,0xaf,0x44,0x35,0xf2,0xdd,0x8f,
+                  0x62,0x0c,0x1e,0xd0,0xb3,0x1d,0xf1,0xb0];
+    for (row, machine) in [(5, &b"apple,j514s"[..]), (6, &b"apple,j516s"[..])] {
+        assert_eq!(BUILDS[row].machine.unwrap().to_bytes(), machine);
+        assert_eq!((BUILDS[row].text_size, BUILDS[row].data_size, BUILDS[row].marker), (0x5c000, 0x114000, 0x58e88));
+        assert_eq!(BUILDS[row].text_sha256, digest);
+    }
+    let measured = Measured { text_size: 0x5c000, data_size: 0x114000, marker: 0x58e88, sha256: digest };
+    assert_eq!(identify(&measured, b"apple,j514s"), Verdict::Pinned(5),
+               "J514S 4118 firmware must pin without a prefix override");
+    assert_eq!(identify(&measured, b"apple,j516s"), Verdict::Pinned(6),
+               "J516S 4118 firmware must pin without a prefix override");
+    for other in [&b"apple,j514c"[..], b"apple,j516c", b"apple,j514m", b"apple,j516m", b"apple,t6030"] {
+        assert_eq!(identify(&measured, other), Verdict::Refused);
+    }
+    for machine in [&b"apple,j514s"[..], b"apple,j516s"] {
+        let mut changed = measured;
+        changed.sha256[31] ^= 1;
+        assert_eq!(identify(&changed, machine), Verdict::Refused);
+        changed = measured; changed.text_size += 0x1000;
+        assert_eq!(identify(&changed, machine), Verdict::Refused);
+        changed = measured; changed.data_size += 0x1000;
+        assert_eq!(identify(&changed, machine), Verdict::Refused);
+        changed = measured; changed.marker += 8;
+        assert_eq!(identify(&changed, machine), Verdict::Refused);
+    }
     for error in [0, -517, -12] {
         INIT_ERROR.set(error); let shared = Arc::new(Shared); let result = Rtkit::new(&dev, &shared);
         assert_eq!(result.is_ok(), error == 0);
diff --git a/tools/asahi/g15-zero-words-tests.py b/tools/asahi/g15-zero-words-tests.py
index 05d29398a1ca16..5236ccbce4ceaf 100644
--- a/tools/asahi/g15-zero-words-tests.py
+++ b/tools/asahi/g15-zero-words-tests.py
@@ -16,11 +16,12 @@
 gated on CONFIG_DRM_ASAHI_G15 for the T8122 runtime without the G15 backend
 (one #[cfg] line; the tables are unchanged). Its T6030 configuration module is
 independently pinned to the original bytes,
-except for the J514S B0 FirmwareBuild row and the J514S cd05 FirmwareBuild row
-added to its firmware table: the module is the original pinned bytes (0079ae08)
-plus those two 15-line rows, and the whole hw.rs pin was refreshed with each
-(with the cd05 row removed, both pins are their earlier values e9b80be9 and
-cab592b5). prepare_board() is pinned too;
+except for the J514S B0 FirmwareBuild row, the J514S cd05 and J516S cd05
+FirmwareBuild rows and the J514S 4118 and J516S 4118 FirmwareBuild rows added
+to its firmware table: the module is the original pinned bytes (0079ae08) plus
+those five rows, and the whole hw.rs pin was refreshed with each (with the 4118
+rows removed, both pins are their earlier values fb2118b6 and 2667963a; with
+the cd05 rows also removed, e9b80be9 and cab592b5). prepare_board() is pinned too;
 it was refreshed for the same Board change (its T6030 arm is unchanged).
 """
 
@@ -37,11 +38,11 @@
 GOLDEN_FILES = {
     "board/data.rs": "7c5ff1077ca3296cbfc9e7144294162b6dea78a3774c38eeed4b0f59a14d7a5c",
     "board/template.rs": "286872f5474a67534f214e83e659253299f85143f3dc59035fa80894022e2549",
-    "hw.rs": "66df80458865ccd0c701145759e6fd8fd1f5a6695a98a7a318b38fbc1368a001",
+    "hw.rs": "76d91bb3cd4c4b676ac13572a756d404cad81e2dc07e5b0bf48dce7e114011e0",
     "power/idle.rs": "4928ecf7699b3ca85ff5143eb6e996efd40d47321e29a238a02c8873bc9f102c",
 }
 GOLDEN_FUNCTIONS = {
-    ("hw.rs", "pub(crate) mod t6030 {"): "d6c3020007646cba504db26bdfe5232e45185aba1d4603931da9a8d29bec40de",
+    ("hw.rs", "pub(crate) mod t6030 {"): "4016ec0d46831482382a92791b625e10fb2f6e4e28115a9498fdde0776f82e52",
     ("initdata.rs", "fn templates("): "c3115c9926d3d7d93317cb8510e93b04f30b0c256811d7137568e822dd93b8ee",
     ("initdata.rs", "pub(crate) fn prepare_board("): "ebef64ab87ef7b1f994eb7fa2a2424d05bc4fc9e88cbfbf18e51570bdfc4222d",
     ("board.rs", "pub(crate) fn from_adt("): "cecd0b28db5bd94d3b75c1bbb5f35204e8bf0699f74e5b3d08228c59025f6ac2",