MIPS: Loongson64: Load built-in dtbs

Load proper dtb according to firmware passed parameters and
CPU PRID.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Co-developed-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/mach-loongson64/builtin_dtbs.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019 Jiaxun Yang <jiaxun.yang@flygoat.com>
+ *
+ * Built-in Generic dtbs for MACH_LOONGSON64
+ */
+
+#ifndef __ASM_MACH_LOONGSON64_BUILTIN_DTBS_H_
+#define __ASM_MACH_LOONGSON64_BUILTIN_DTBS_H_
+
+extern u32 __dtb_loongson3_4core_rs780e_begin[];
+extern u32 __dtb_loongson3_8core_rs780e_begin[];
+#endif

arch/mips/include/asm/mach-loongson64/loongson.h

@@ -25,6 +25,7 @@ extern const struct plat_smp_ops loongson3_smp_ops;
 /* loongson-specific command line, env and memory initialization */
 extern void __init prom_init_memory(void);
 extern void __init prom_init_env(void);
+extern void *loongson_fdt_blob;
 
 /* irq operation functions */
 extern void mach_irq_dispatch(unsigned int pending);

arch/mips/loongson64/env.c

@@ -17,6 +17,7 @@
 #include <asm/bootinfo.h>
 #include <loongson.h>
 #include <boot_param.h>
+#include <builtin_dtbs.h>
 #include <workarounds.h>
 
 u32 cpu_clock_freq;
@@ -120,6 +121,28 @@ void __init prom_init_env(void)
 		loongson_sysconf.cores_per_node - 1) /
 		loongson_sysconf.cores_per_node;
 
+	if ((read_c0_prid() & PRID_IMP_MASK) == PRID_IMP_LOONGSON_64C) {
+		switch (read_c0_prid() & PRID_REV_MASK) {
+		case PRID_REV_LOONGSON3A_R1:
+		case PRID_REV_LOONGSON3A_R2_0:
+		case PRID_REV_LOONGSON3A_R2_1:
+		case PRID_REV_LOONGSON3A_R3_0:
+		case PRID_REV_LOONGSON3A_R3_1:
+			loongson_fdt_blob = __dtb_loongson3_4core_rs780e_begin;
+			break;
+		case PRID_REV_LOONGSON3B_R1:
+		case PRID_REV_LOONGSON3B_R2:
+			loongson_fdt_blob = __dtb_loongson3_8core_rs780e_begin;
+			break;
+		default:
+			break;
+		}
+	}
+
+
+	if (!loongson_fdt_blob)
+		pr_err("Failed to determine built-in Loongson64 dtb\n");
+
 	loongson_sysconf.pci_mem_start_addr = eirq_source->pci_mem_start_addr;
 	loongson_sysconf.pci_mem_end_addr = eirq_source->pci_mem_end_addr;
 	loongson_sysconf.pci_io_base = eirq_source->pci_io_start_addr;

arch/mips/loongson64/setup.c

@@ -8,9 +8,15 @@
 
 #include <asm/wbflush.h>
 #include <asm/bootinfo.h>
+#include <linux/libfdt.h>
+#include <linux/of_fdt.h>
+
+#include <asm/prom.h>
 
 #include <loongson.h>
 
+void *loongson_fdt_blob;
+
 static void wbflush_loongson(void)
 {
 	asm(".set\tpush\n\t"
@@ -27,4 +33,14 @@ EXPORT_SYMBOL(__wbflush);
 
 void __init plat_mem_setup(void)
 {
+	if (loongson_fdt_blob)
+		__dt_setup_arch(loongson_fdt_blob);
+}
+
+void __init device_tree_init(void)
+{
+	if (!initial_boot_params)
+		return;
+
+	unflatten_and_copy_device_tree();
 }