board: siemens: iot2050: Split the build for PG1 and PG2

Due to different signature keys, the PG1 and the PG2 boards can no
longer use the same FSBL (tiboot3). This makes it impossible anyway to
maintaine a single flash.bin for both variants, so we can also split the
build.

A new target is added to indicates the build is for PG1 vs. PG2 boards.
Hence now the variants have separated defconfig files.

The runtime board_is_sr1() check does make no sense anymore, so remove
it and replace with build time check.

Documentation is updated accordingly. New binary artifacts are already
available via meta-iot2050.

Signed-off-by: Su Baocheng <baocheng.su@siemens.com>
[Jan: refactor config option into targets, tweak some wordings]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
diff --git a/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi b/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
index 2705837..3135ad0 100644
--- a/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
+++ b/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) Siemens AG, 2020-2021
+ * Copyright (c) Siemens AG, 2020-2022
  *
  * Authors:
  *   Jan Kiszka <jan.kiszka@siemens.com>
@@ -17,7 +17,11 @@
 
 		blob-ext@0x000000 {
 			offset = <0x000000>;
-			filename = "tiboot3.bin";
+#ifdef CONFIG_TARGET_IOT2050_A53_PG1
+			filename = "seboot_pg1.bin";
+#else
+			filename = "seboot_pg2.bin";
+#endif
 			missing-msg = "iot2050-seboot";
 		};
 
@@ -43,42 +47,30 @@
 				};
 
 				fdt-iot2050-basic {
-					description = "k3-am6528-iot2050-basic.dtb";
+					description = "k3-am6528-iot2050-basic*.dtb";
 					type = "flat_dt";
 					arch = "arm64";
 					compression = "none";
 					blob {
+#ifdef CONFIG_TARGET_IOT2050_A53_PG1
 						filename = "arch/arm/dts/k3-am6528-iot2050-basic.dtb";
-					};
-				};
-
-				fdt-iot2050-basic-pg2 {
-					description = "k3-am6528-iot2050-basic-pg2.dtb";
-					type = "flat_dt";
-					arch = "arm64";
-					compression = "none";
-					blob {
+#else
 						filename = "arch/arm/dts/k3-am6528-iot2050-basic-pg2.dtb";
+#endif
 					};
 				};
 
 				fdt-iot2050-advanced {
-					description = "k3-am6548-iot2050-advanced.dtb";
+					description = "k3-am6548-iot2050-advanced*.dtb";
 					type = "flat_dt";
 					arch = "arm64";
 					compression = "none";
 					blob {
+#ifdef CONFIG_TARGET_IOT2050_A53_PG1
 						filename = "arch/arm/dts/k3-am6548-iot2050-advanced.dtb";
-					};
-				};
-
-				fdt-iot2050-advanced-pg2 {
-					description = "k3-am6548-iot2050-advanced-pg2.dtb";
-					type = "flat_dt";
-					arch = "arm64";
-					compression = "none";
-					blob {
+#else
 						filename = "arch/arm/dts/k3-am6548-iot2050-advanced-pg2.dtb";
+#endif
 					};
 				};
 
@@ -108,15 +100,6 @@
 #endif
 				};
 
-				conf-iot2050-basic-pg2 {
-					description = "iot2050-basic-pg2";
-					firmware = "u-boot";
-					fdt = "fdt-iot2050-basic-pg2";
-#ifdef CONFIG_WDT_K3_RTI_FW_FILE
-					loadables = "k3-rti-wdt-firmware";
-#endif
-				};
-
 				conf-iot2050-advanced {
 					description = "iot2050-advanced";
 					firmware = "u-boot";
@@ -125,15 +108,6 @@
 					loadables = "k3-rti-wdt-firmware";
 #endif
 				};
-
-				conf-iot2050-advanced-pg2 {
-					description = "iot2050-advanced-pg2";
-					firmware = "u-boot";
-					fdt = "fdt-iot2050-advanced-pg2";
-#ifdef CONFIG_WDT_K3_RTI_FW_FILE
-					loadables = "k3-rti-wdt-firmware";
-#endif
-				};
 			};
 		};
 
@@ -150,28 +124,24 @@
 			fill-byte = [00];
 		};
 
-		/* PG1 sysfw, basic variant */
+		/* sysfw, basic variant */
 		blob-ext@0x6c0000 {
 			offset = <0x6c0000>;
-			filename = "sysfw.itb";
+#ifdef CONFIG_TARGET_IOT2050_A53_PG1
+			filename = "sysfw_sr1.itb";
+#else
+			filename = "sysfw_sr2.itb";
+#endif
 			missing-msg = "iot2050-sysfw";
 		};
-		/* PG1 sysfw, advanced variant */
+		/* sysfw, advanced variant */
 		blob-ext@0x740000 {
 			offset = <0x740000>;
-			filename = "sysfw.itb_HS";
-			missing-msg = "iot2050-sysfw";
-		};
-		/* PG2 sysfw, basic variant */
-		blob-ext@0x7c0000 {
-			offset = <0x7c0000>;
-			filename = "sysfw_sr2.itb";
-			missing-msg = "iot2050-sysfw";
-		};
-		/* PG2 sysfw, advanced variant */
-		blob-ext@0x840000 {
-			offset = <0x840000>;
+#ifdef CONFIG_TARGET_IOT2050_A53_PG1
+			filename = "sysfw_sr1.itb_HS";
+#else
 			filename = "sysfw_sr2.itb_HS";
+#endif
 			missing-msg = "iot2050-sysfw";
 		};
 	};