Blackfin arch: unify the duplicated _real_start functions

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/arch/blackfin/mach-common/head.S b/arch/blackfin/mach-common/head.S
new file mode 100644
index 000000000000..8514da587557
--- /dev/null
+++ b/arch/blackfin/mach-common/head.S
@@ -0,0 +1,76 @@
+/*
+ * Common Blackfin startup code
+ *
+ * Copyright 2004-2008 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/blackfin.h>
+#include <asm/trace.h>
+
+/* A little BF561 glue ... */
+#ifndef WDOG_CTL
+# define WDOG_CTL WDOGA_CTL
+#endif
+
+__INIT
+
+ENTRY(_real_start)
+        /* Enable nested interrupts */
+        [--sp] = reti;
+
+        /* watchdog off for now */
+        p0.l = lo(WDOG_CTL);
+        p0.h = hi(WDOG_CTL);
+        r0 = 0xAD6(z);
+        w[p0] = r0;
+        ssync;
+
+        /* Zero out the bss region
+         * Note: this will fail if bss is 0 bytes ...
+         */
+        r0 = 0 (z);
+        r1.l = ___bss_start;
+        r1.h = ___bss_start;
+        r2.l = ___bss_stop;
+        r2.h = ___bss_stop;
+        r2 = r2 - r1;
+        r2 >>= 2;
+        p1 = r1;
+        p2 = r2;
+        lsetup (.L_clear_bss, .L_clear_bss) lc0 = p2;
+.L_clear_bss:
+        [p1++] = r0;
+
+        /* In case there is a NULL pointer reference,
+         * zero out region before stext
+         */
+        p1 = r0;
+        r2.l = __stext;
+        r2.h = __stext;
+        r2 >>= 2;
+        p2 = r2;
+        lsetup (.L_clear_zero, .L_clear_zero) lc0 = p2;
+.L_clear_zero:
+        [p1++] = r0;
+
+        /* Pass the u-boot arguments to the global value command line */
+        R0 = R7;
+        call _cmdline_init;
+
+        /* Load the current thread pointer and stack */
+        sp.l = _init_thread_union;
+        sp.h = _init_thread_union;
+        p1 = THREAD_SIZE (z);
+        sp = sp + p1;
+        usp = sp;
+        fp = sp;
+        jump.l _start_kernel;
+ENDPROC(_real_start)
+
+__FINIT