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Diffstat (limited to 'arch/mips/dec/boot/decstation.c')
-rw-r--r--arch/mips/dec/boot/decstation.c83
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);
+}