drm/apple: T6041 (M4 Pro/Max) displays on desktop 26.6 firmware (carries #445)

Documentation/devicetree/bindings/phy/apple,t6040-atcphy.yaml

@@ -11,10 +11,13 @@ maintainers:
 
 description: >
   The Type-C PHY of the Apple T6040 (M4 Pro) SoC, as used for USB2 and USB3
-  host operation. USB3 is brought up by a PHY coprocessor running RTKit
-  firmware, reached through an ASC mailbox. The PHY also provides the reset
-  line of the attached DWC3 controller and acts as the Type-C orientation
-  switch.
+  host operation and for DisplayPort. USB3 is brought up by a PHY coprocessor
+  running RTKit firmware, reached through an ASC mailbox. The PHY also
+  provides the reset line of the attached DWC3 controller and acts as the
+  Type-C orientation switch and, where the port carries DisplayPort alt mode,
+  as its mode switch. The same PHY drives the fixed DisplayPort link of an
+  HDMI converter; that instance has no USB controller behind it and therefore
+  no PIPE interface.
 
 $defs:
   apple,tunable:
@@ -35,6 +38,7 @@ properties:
     const: apple,t6040-atcphy
 
   reg:
+    minItems: 10
     items:
       - description: USB2 PHY controls
       - description: USB2 event counter controls
@@ -49,21 +53,37 @@ properties:
       - description: ATC common configuration controls
 
   reg-names:
-    items:
-      - const: bank0
-      - const: bank1
-      - const: pipehandler
-      - const: core
-      - const: cfg
-      - const: cpu
-      - const: cpu-data
-      - const: axi2af
-      - const: axi2af-lioa
-      - const: fabric
-      - const: common-cfg
+    oneOf:
+      - items:
+          - const: bank0
+          - const: bank1
+          - const: pipehandler
+          - const: core
+          - const: cfg
+          - const: cpu
+          - const: cpu-data
+          - const: axi2af
+          - const: axi2af-lioa
+          - const: fabric
+          - const: common-cfg
+      - description: A fixed DisplayPort PHY without a USB controller
+        items:
+          - const: bank0
+          - const: bank1
+          - const: core
+          - const: cfg
+          - const: cpu
+          - const: cpu-data
+          - const: axi2af
+          - const: axi2af-lioa
+          - const: fabric
+          - const: common-cfg
 
   "#phy-cells":
     const: 1
+    description: >
+      The PHY type (dt-bindings/phy/phy.h): PHY_TYPE_USB2, PHY_TYPE_USB3 or
+      PHY_TYPE_DP.
 
   "#reset-cells":
     const: 0
@@ -81,9 +101,13 @@ properties:
 
   orientation-switch: true
 
+  mode-switch: true
+
   port:
     $ref: /schemas/graph.yaml#/properties/port
-    description: Link to the SuperSpeed lanes of the Type-C connector.
+    description: >
+      Link to the SuperSpeed lanes of the Type-C connector. Absent on a fixed
+      DisplayPort PHY.
 
   apple,tunable-axi2af:
     $ref: "#/$defs/apple,tunable"
@@ -134,9 +158,24 @@ required:
   - reg
   - reg-names
   - "#phy-cells"
-  - "#reset-cells"
   - power-domains
 
+allOf:
+  - if:
+      properties:
+        reg-names:
+          contains:
+            const: pipehandler
+    then:
+      required:
+        - "#reset-cells"
+    else:
+      properties:
+        "#reset-cells": false
+        orientation-switch: false
+        mode-switch: false
+        port: false
+
 additionalProperties: false
 
 examples:
@@ -170,4 +209,30 @@ examples:
             orientation-switch;
         };
     };
+  - |
+    soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        phy@39aa90000 {
+            compatible = "apple,t6040-atcphy";
+            reg = <0x3 0x9aa90000 0x0 0x4000>,
+                  <0x3 0x9a800000 0x0 0x4000>,
+                  <0x3 0x9b000000 0x0 0x30000>,
+                  <0x3 0x9b200000 0x0 0x4000>,
+                  <0x3 0x9b140000 0x0 0x4000>,
+                  <0x3 0x9b0c0000 0x0 0x10000>,
+                  <0x3 0x98000000 0x0 0x8000>,
+                  <0x3 0x98020000 0x0 0x4000>,
+                  <0x3 0x9b244000 0x0 0x4000>,
+                  <0x3 0x9b250000 0x0 0x4000>;
+            reg-names = "bank0", "bank1", "core", "cfg", "cpu", "cpu-data",
+                        "axi2af", "axi2af-lioa", "fabric", "common-cfg";
+            #phy-cells = <1>;
+            power-domains = <&ps_atc3_common_dp>;
+            mboxes = <&atcphy3_mbox>;
+            mbox-names = "phy-cpu";
+            nonposted-mmio;
+        };
+    };
 ...

drivers/gpu/drm/apple/Kconfig

@@ -14,6 +14,8 @@ config DRM_APPLE
 	select DRM_GEM_SHMEM_HELPER
 	select DRM_GEM_DMA_HELPER
 	select VIDEOMODE_HELPERS
+	# write-combined maps of firmware-placed carveouts (desktop 26.x)
+	select VMAP_PFN
 	depends on BACKLIGHT_CLASS_DEVICE
 	select MULTIPLEXER
 	select DRM_APPLE_FABRIC_CORE

drivers/gpu/drm/apple/Makefile

@@ -14,6 +14,7 @@ appledrm-y += dcpext_drm.o
 appledrm-y += iomfb_v12_3.o
 appledrm-y += iomfb_v13_3.o
 appledrm-y += iomfb_v14_7_tpl.o
+appledrm-y += iomfb_v26_6_desktop.o
 appledrm-y += iomfb_v14_7.o iomfb_v14_7_link.o
 appledrm-$(CONFIG_DRM_APPLE_DCP_T8132) += iomfb_m4.o
 appledrm-y += iomfb_h17p.o

drivers/gpu/drm/apple/afk-fragment.h

@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+#ifndef __APPLE_DCP_AFK_FRAGMENT_H__
+#define __APPLE_DCP_AFK_FRAGMENT_H__
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+/* Native 26.6 AV traffic: repeated 8-byte header, then up to 1028 bytes
+ * of the logical message (timestamp, subheader, descriptor and payload).
+ * The total length is repeated and the endpoint sequence advances on every
+ * fragment, including 255 -> 0. Messages are not interleaved on an endpoint.
+ */
+#define AFK_COMPACT_FRAGMENT_SIZE 1028U
+#define AFK_COMPACT_MESSAGE_MAX (1024U * 1024U)
+
+struct afk_fragment_state {
+	u32 total;
+	u32 received;
+	u16 intf_id;
+	u8 next_seq;
+};
+
+/* Validate before allocating/copying. Returns 1 on completion, 0 while
+ * collecting, or an error. The caller discards the whole message on error.
+ */
+static inline int afk_fragment_accept(struct afk_fragment_state *s,
+				      u16 intf_id, u8 seq, u32 total, u32 size)
+{
+	if (total < 16 || total > AFK_COMPACT_MESSAGE_MAX || !size || size > total)
+		return -EMSGSIZE;
+	if (s->received && (s->total != total || s->intf_id != intf_id ||
+			    s->next_seq != seq))
+		return -EPROTO;
+	if (size > total - s->received)
+		return -EMSGSIZE;
+
+	s->total = total;
+	s->intf_id = intf_id;
+	s->next_seq = seq + 1;
+	s->received += size;
+	return s->received == total;
+}
+
+#endif