armv7: unify stage hand-off routines

This replaces the current stage-specific exit/entry functions with
generic versions. Now all stages compile with stage_entry(), which
is placed at .text.stage_entry.armv7, and stage_exit().

Snow's ramstage files are also updated to avoid build breakage.

Change-Id: I953a2c4b8121bd4b66c3362557997a9ca3aa53b0
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2254
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)

1 files changed, 45 insertions, 0 deletions

diff --git a/src/arch/armv7/stages.c b/src/arch/armv7/stages.c
new file mode 100644
index 0000000000..fd4374ff9c
--- /dev/null
+++ b/src/arch/armv7/stages.c
@@ -0,0 +1,45 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2012 The ChromiumOS Authors.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * This file contains entry/exit functions for each stage during coreboot
+ * execution (bootblock entry and ramstage exit will depend on external
+ * loading.
+ *
+ * Unlike other files, this one should be compiled with a -m option to
+ * specify a pre-determined instruction set. The is to ensure consistency
+ * in the CPU operating mode (ARM or Thumb) when hand-off between stages
+ * occurs.
+ *
+ * Entry points must be placed at the location the previous stage jumps
+ * to (the lowest address in the stage image). This is done by giving
+ * stage_entry() its own section in .text and placing it first in the
+ * linker script.
+ */
+
+#include <arch/stages.h>
+
+void stage_entry(void)
+{
+	main();
+}
+
+void stage_exit(unsigned long addr)
+{
+	__attribute__((noreturn)) void (*doit)(void) = (void *)addr;
+	doit();
+}