From: kettenis <kettenis@openbsd.org>
Date: Fri, 29 Mar 2024 22:11:34 +0000 (+0000)
Subject: Use SBI calls to reboot or power down the machine when the firmware
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=114916adda2ad533b1f9dddde71bb75e4cde5991;p=openbsd

Use SBI calls to reboot or power down the machine when the firmware
supports them.

ok jca@
---

diff --git a/sys/arch/riscv64/include/sbi.h b/sys/arch/riscv64/include/sbi.h
index 802ae7f68a0..e5117ed752a 100644
--- a/sys/arch/riscv64/include/sbi.h
+++ b/sys/arch/riscv64/include/sbi.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sbi.h,v 1.5 2022/08/29 02:01:18 jsg Exp $	*/
+/*	$OpenBSD: sbi.h,v 1.6 2024/03/29 22:11:34 kettenis Exp $	*/
 
 /*-
  * Copyright (c) 2016-2017 Ruslan Bukin <br@bsdpad.com>
@@ -76,6 +76,13 @@
 #define	 SBI_HSM_STATUS_START_PENDING	2
 #define	 SBI_HSM_STATUS_STOP_PENDING	3
 
+/* System Reset Extension */
+#define	SBI_EXT_ID_SRST			0x53525354
+#define	SBI_SRST_RESET			0
+#define	 SBI_SRST_RESET_SHUTDOWN	0
+#define	 SBI_SRST_RESET_COLD_REBOOT	1
+#define	 SBI_SRST_RESET_WARM_REBOOT	2
+
 /* Legacy Extensions */
 #define	SBI_SET_TIMER			0
 #define	SBI_CONSOLE_PUTCHAR		1
diff --git a/sys/arch/riscv64/riscv64/sbi.c b/sys/arch/riscv64/riscv64/sbi.c
index 57b90aad434..b7c86900695 100644
--- a/sys/arch/riscv64/riscv64/sbi.c
+++ b/sys/arch/riscv64/riscv64/sbi.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sbi.c,v 1.7 2022/12/06 00:11:23 jca Exp $	*/
+/*	$OpenBSD: sbi.c,v 1.8 2024/03/29 22:11:34 kettenis Exp $	*/
 
 /*-
  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
@@ -35,6 +35,9 @@
 
 #include <dev/cons.h>
 
+extern void (*cpuresetfn)(void);
+extern void (*powerdownfn)(void);
+
 /* SBI Implementation-Specific Definitions */
 #define	OPENSBI_VERSION_MAJOR_OFFSET	16
 #define	OPENSBI_VERSION_MINOR_MASK	0xFFFF
@@ -124,6 +127,20 @@ sbi_hsm_hart_status(u_long hart)
 
 #endif
 
+void
+sbi_reset(void)
+{
+	SBI_CALL2(SBI_EXT_ID_SRST, SBI_SRST_RESET,
+	    SBI_SRST_RESET_WARM_REBOOT, 0);
+}
+
+void
+sbi_powerdown(void)
+{
+	SBI_CALL2(SBI_EXT_ID_SRST, SBI_SRST_RESET,
+	    SBI_SRST_RESET_SHUTDOWN, 0);
+}
+
 void
 sbi_init(void)
 {
@@ -167,6 +184,15 @@ sbi_init(void)
 	    "SBI doesn't implement sbi_remote_sfence_vma_asid()");
 	KASSERTMSG(sbi_probe_extension(SBI_SHUTDOWN) != 0,
 	    "SBI doesn't implement sbi_shutdown()");
+
+	/*
+	 * Implement reboot and power down if the System Reset
+	 * Extension is implemented.
+	 */
+	if (sbi_probe_extension(SBI_EXT_ID_SRST) != 0) {
+		cpuresetfn = sbi_reset;
+		powerdownfn = sbi_powerdown;
+	}
 }
 
 /*