1 files changed, 83 insertions, 0 deletions
diff --git a/arch/mips/dec/boot/decstation.c b/arch/mips/dec/boot/decstation.c
new file mode 100644
index 00000000000..56fd4277555
--- /dev/null
+++ b/arch/mips/dec/boot/decstation.c
@@ -0,0 +1,83 @@
+/*
+ * arch/mips/dec/decstation.c
+ */
+
+#define RELOC
+#define INITRD
+#define DEBUG_BOOT
+
+/*
+ * Magic number indicating REX PROM available on DECSTATION.
+ */
+#define	REX_PROM_MAGIC		0x30464354
+
+#define REX_PROM_CLEARCACHE	0x7c/4
+#define REX_PROM_PRINTF		0x30/4
+
+#define VEC_RESET		0xBFC00000		/* Prom base address */
+#define	PMAX_PROM_ENTRY(x)	(VEC_RESET+((x)*8))	/* Prom jump table */
+#define	PMAX_PROM_PRINTF	PMAX_PROM_ENTRY(17)
+
+#define PARAM	(k_start + 0x2000)
+
+#define LOADER_TYPE (*(unsigned char *) (PARAM+0x210))
+#define INITRD_START (*(unsigned long *) (PARAM+0x218))
+#define INITRD_SIZE (*(unsigned long *) (PARAM+0x21c))
+
+extern int _ftext, _end;		/* begin and end of kernel image */
+extern void kernel_entry(int, char **, unsigned long, int *);
+
+void * memcpy(void * dest, const void *src, unsigned int count)
+{
+	unsigned long *tmp = (unsigned long *) dest, *s = (unsigned long *) src;
+
+	count >>= 2;
+	while (count--)
+		*tmp++ = *s++;
+
+	return dest;
+}
+
+void dec_entry(int argc, char **argv,
+	       unsigned long magic, int *prom_vec)
+{
+	void (*rex_clear_cache)(void);
+	int (*prom_printf)(char *, ...);
+	unsigned long k_start, len;
+
+	/*
+	 * The DS5100 leaves cpu with BEV enabled, clear it.
+	 */
+	asm(	"lui\t$8,0x3000\n\t"
+		"mtc0\t$8,$12\n\t"
+		".section\t.sdata\n\t"
+		".section\t.sbss\n\t"
+		".section\t.text"
+		: : : "$8");
+
+#ifdef DEBUG_BOOT
+	if (magic == REX_PROM_MAGIC) {
+	prom_printf = (int (*)(char *, ...)) *(prom_vec + REX_PROM_PRINTF);
+	} else {
+		prom_printf = (int (*)(char *, ...)) PMAX_PROM_PRINTF;
+	}
+	prom_printf("Launching kernel...\n");
+#endif
+
+	k_start = (unsigned long) (&kernel_entry) & 0xffff0000;
+
+#ifdef RELOC
+	/*
+	 * Now copy kernel image to its destination.
+	 */
+	len = ((unsigned long) (&_end) - k_start);
+	memcpy((void *)k_start, &_ftext, len);
+#endif
+
+	if (magic == REX_PROM_MAGIC) {
+		rex_clear_cache = (void (*)(void)) * (prom_vec + REX_PROM_CLEARCACHE);
+		rex_clear_cache();
+	}
+
+	kernel_entry(argc, argv, magic, prom_vec);
+}