1 files changed, 132 insertions, 0 deletions
diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
new file mode 100644
index 000000000..1e91155be
--- /dev/null
+++ b/arch/mips/boot/compressed/decompress.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2001 MontaVista Software Inc.
+ * Author: Matt Porter <mporter@mvista.com>
+ *
+ * Copyright (C) 2009 Lemote, Inc.
+ * Author: Wu Zhangjin <wuzhangjin@gmail.com>
+ */
+
+#define DISABLE_BRANCH_PROFILING
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/libfdt.h>
+
+#include <asm/addrspace.h>
+#include <asm/unaligned.h>
+
+/*
+ * These two variables specify the free mem region
+ * that can be used for temporary malloc area
+ */
+unsigned long free_mem_ptr;
+unsigned long free_mem_end_ptr;
+
+/* The linker tells us where the image is. */
+extern unsigned char __image_begin, __image_end;
+
+/* debug interfaces  */
+#ifdef CONFIG_DEBUG_ZBOOT
+extern void puts(const char *s);
+extern void puthex(unsigned long long val);
+#else
+#define puts(s) do {} while (0)
+#define puthex(val) do {} while (0)
+#endif
+
+extern char __appended_dtb[];
+
+void error(char *x)
+{
+	puts("\n\n");
+	puts(x);
+	puts("\n\n -- System halted");
+
+	while (1)
+		;	/* Halt */
+}
+
+/* activate the code for pre-boot environment */
+#define STATIC static
+
+#ifdef CONFIG_KERNEL_GZIP
+#include "../../../../lib/decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_BZIP2
+#include "../../../../lib/decompress_bunzip2.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZ4
+#include "../../../../lib/decompress_unlz4.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZMA
+#include "../../../../lib/decompress_unlzma.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZO
+#include "../../../../lib/decompress_unlzo.c"
+#endif
+
+#ifdef CONFIG_KERNEL_XZ
+#include "../../../../lib/decompress_unxz.c"
+#endif
+
+#ifdef CONFIG_KERNEL_ZSTD
+#include "../../../../lib/decompress_unzstd.c"
+#endif
+
+const unsigned long __stack_chk_guard = 0x000a0dff;
+
+void __stack_chk_fail(void)
+{
+	error("stack-protector: Kernel stack is corrupted\n");
+}
+
+void decompress_kernel(unsigned long boot_heap_start)
+{
+	unsigned long zimage_start, zimage_size;
+
+	zimage_start = (unsigned long)(&__image_begin);
+	zimage_size = (unsigned long)(&__image_end) -
+	    (unsigned long)(&__image_begin);
+
+	puts("zimage at:     ");
+	puthex(zimage_start);
+	puts(" ");
+	puthex(zimage_size + zimage_start);
+	puts("\n");
+
+	/* This area are prepared for mallocing when decompressing */
+	free_mem_ptr = boot_heap_start;
+	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
+
+	/* Display standard Linux/MIPS boot prompt */
+	puts("Uncompressing Linux at load address ");
+	puthex(VMLINUX_LOAD_ADDRESS_ULL);
+	puts("\n");
+
+	/* Decompress the kernel with according algorithm */
+	__decompress((char *)zimage_start, zimage_size, 0, 0,
+		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
+
+	if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
+	    fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
+		unsigned int image_size, dtb_size;
+
+		dtb_size = fdt_totalsize((void *)&__appended_dtb);
+
+		/* last four bytes is always image size in little endian */
+		image_size = get_unaligned_le32((void *)&__image_end - 4);
+
+		/* copy dtb to where the booted kernel will expect it */
+		memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
+		       __appended_dtb, dtb_size);
+	}
+
+	/* FIXME: should we flush cache here? */
+	puts("Now, booting the kernel...\n");
+}