kboot: dcpext: t8112/t602x: Use dt_reserve_asc_firmware() for dcpext*

Avoids manually matching pre-mapped memory against "carveout-memory-map"
and maintaining a list of hopefully static carveoout regions.
Leave t8103 and t600x alone for now. Porting dcp over to this a littles
harder since that needs additional handling for regions mapped to
"dart-disp0?".

src/kboot.c

@@ -1635,6 +1635,46 @@ static int dt_reserve_asc_firmware(const char *adt_path, const char *adt_path_al
     return 0;
 }
 
+static const char dcpext_aliases[][8] = {
+    "dcpext",  "dcpext0", "dcpext1", "dcpext2", "dcpext3",
+    "dcpext4", "dcpext5", "dcpext6", "dcpext7",
+};
+
+static int dt_reserve_dcpext_firmware(void)
+{
+    /* reserve asc for all  */
+    for (size_t n = 0; n < ARRAY_SIZE(dcpext_aliases); n++) {
+        const char *dcpext_alias = dcpext_aliases[n];
+        char adt_path[48];
+
+        snprintf(adt_path, sizeof(adt_path) - 1, "/arm-io/%s/iop-%s-nub", dcpext_alias,
+                 dcpext_alias);
+        adt_path[sizeof(adt_path) - 1] = '\0';
+
+        if (adt_path_offset(adt, adt_path) < 0)
+            continue;
+
+        int dcpext_node = fdt_path_offset(dt, dcpext_alias);
+        if (dcpext_node < 0)
+            continue;
+
+        int ret = dt_reserve_asc_firmware(adt_path, NULL, dcpext_alias, true, 0);
+        if (ret < 0)
+            bail("FDT: reserving ASC firmware for %s failed!\n", dcpext_alias);
+
+        ret = dt_set_dcp_firmware(dcpext_alias);
+        if (ret)
+            continue;
+
+        // refresh dcpext_node
+        dcpext_node = fdt_path_offset(dt, dcpext_alias);
+        if ((dcpext_node < 0) || (fdt_setprop_string(dt, dcpext_node, "status", "okay") < 0))
+            printf("FDT: failed to enable '%s'\n", dcpext_alias);
+    }
+
+    return 0;
+}
+
 static struct disp_mapping disp_reserved_regions_t8103[] = {
     {"region-id-50", "dcp_data", true, false, false},
     {"region-id-57", "region57", true, false, false},
@@ -1649,20 +1689,14 @@ static struct disp_mapping dcpext_reserved_regions_t8103[] = {
 };
 
 static struct disp_mapping disp_reserved_regions_t8112[] = {
-    {"region-id-49", "dcp_txt", true, false, false},
+    {"region-id-49", "asc-firmware", true, false, false},
     {"region-id-50", "dcp_data", true, false, false},
     {"region-id-57", "region57", true, false, false},
     // The 2 following regions are mapped in dart-dcp sid 5 and dart-disp0 sid 0 and 4
     {"region-id-94", "region94", true, true, false},
     {"region-id-95", "region95", true, false, true},
 };
 
-static struct disp_mapping dcpext_reserved_regions_t8112[] = {
-    {"region-id-49", "dcp_txt", true, false, false},
-    {"region-id-73", "dcpext_data", true, false, false},
-    {"region-id-74", "region74", true, false, false},
-};
-
 static struct disp_mapping disp_reserved_regions_t600x[] = {
     {"region-id-50", "dcp_data", true, false, false},
     {"region-id-57", "region57", true, false, false},
@@ -1711,7 +1745,7 @@ static struct disp_mapping dcpext_reserved_regions_t600x[MAX_DCPEXT][2] = {
 };
 
 static struct disp_mapping disp_reserved_regions_t602x[] = {
-    {"region-id-49", "dcp_txt", true, false, false},
+    {"region-id-49", "asc-firmware", true, false, false},
     {"region-id-50", "dcp_data", true, false, false},
     {"region-id-57", "region57", true, false, false},
     // The 2 following regions are mapped in dart-dcp sid 0 and dart-disp0 sid 0 and 4
@@ -1721,8 +1755,6 @@ static struct disp_mapping disp_reserved_regions_t602x[] = {
     {"region-id-157", "region157", true, true, false},
 };
 
-#define ARRAY_SIZE(s) (sizeof(s) / sizeof((s)[0]))
-
 static int dt_set_display(void)
 {
     /* lock dart-disp0 to prevent old software from resetting it */
@@ -1736,6 +1768,7 @@ static int dt_set_display(void)
      * they are missing. */
 
     int ret = 0;
+    char dcp_alias[8] = "dcp";
 
     if (!fdt_node_check_compatible(dt, 0, "apple,t8103")) {
         ret = dt_carveout_reserved_regions("dcp", "disp0", "disp0_piodma",
@@ -1752,9 +1785,6 @@ static int dt_set_display(void)
                                            ARRAY_SIZE(disp_reserved_regions_t8112));
         if (ret)
             return ret;
-
-        ret = dt_carveout_reserved_regions("dcpext", NULL, NULL, dcpext_reserved_regions_t8112,
-                                           ARRAY_SIZE(dcpext_reserved_regions_t8112));
     } else if (!fdt_node_check_compatible(dt, 0, "apple,t6000") ||
                !fdt_node_check_compatible(dt, 0, "apple,t6001") ||
                !fdt_node_check_compatible(dt, 0, "apple,t6002")) {
@@ -1779,14 +1809,28 @@ static int dt_set_display(void)
                                            ARRAY_SIZE(disp_reserved_regions_t602x));
         if (ret)
             return ret;
+    } else if (!fdt_node_check_compatible(dt, 0, "apple,t6022")) {
+        // Set dcp_alias to "dcpext4" on  M2 Ultra, cmp. display.c
+        strncpy(dcp_alias, "dcpext4", sizeof(dcp_alias));
+        dcp_alias[sizeof(dcp_alias) - 1] = '\0';
     } else {
         printf("FDT: unknown compatible, skip display reserved-memory setup\n");
         return 0;
     }
     if (ret)
         return ret;
 
-    return dt_vram_reserved_region("dcp", "disp0");
+    /*
+     * Ignore errors for dcpext firmware reservation, nodes should be disabled
+     * if the reservation fails allowing basic operation with just dcp.
+     */
+    if (!fdt_node_check_compatible(dt, 0, "apple,t8112") ||
+        !fdt_node_check_compatible(dt, 0, "apple,t6020") ||
+        !fdt_node_check_compatible(dt, 0, "apple,t6021") ||
+        !fdt_node_check_compatible(dt, 0, "apple,t6022"))
+        dt_reserve_dcpext_firmware();
+
+    return dt_vram_reserved_region(dcp_alias, "disp0");
 }
 
 static int dt_set_sio_fwdata(void)