riscv: add support smp_pause / smp_resume

See https://doc.coreboot.org/arch/riscv/ we know that we need to execute
smp_pause at the start of each stage and smp_resume at the end of each
stage.

Change-Id: I6f8159637bfb15f54f0abeb335de2ba6e9cf82fb
Signed-off-by: Xiang Wang <wxjstz@126.com>
Reviewed-on: https://review.coreboot.org/29023
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Philipp Hug <philipp@hug.cx>

1 files changed, 33 insertions, 0 deletions

diff --git a/src/arch/riscv/include/arch/smp/smp.h b/src/arch/riscv/include/arch/smp/smp.h
new file mode 100644
index 000000000000..e9964044767c
--- /dev/null
+++ b/src/arch/riscv/include/arch/smp/smp.h
@@ -0,0 +1,33 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 HardenedLinux.
+ *
+ * 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.
+ */
+
+#ifndef _RISCV_SMP_H
+#define _RISCV_SMP_H
+
+/*
+ * This function is used to pause smp. Only the hart with hartid equal
+ * to working_hartid can be returned from smp_pause, other harts will
+ * enter halt and wait for wakeup
+ */
+void smp_pause(int working_hartid);
+
+/*
+ * This function is used to wake up the harts that are halted by the
+ * smp_pause function. And this function will not return, all hart will
+ * jump to fn execution, and arg is the argument of the function fn.
+ */
+void smp_resume(void (*fn)(void *), void *arg);
+
+#endif