[riscv] Add support for reboot and power off via SBI

Signed-off-by: Michael Brown <mcb30@ipxe.org>

5 files changed, 120 insertions, 0 deletions

diff --git a/src/arch/riscv/include/bits/errfile.h b/src/arch/riscv/include/bits/errfile.h
index 2b1202147..e97c71a37 100644
--- a/src/arch/riscv/include/bits/errfile.h
+++ b/src/arch/riscv/include/bits/errfile.h
@@ -14,6 +14,8 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  * @{
  */
 
+#define ERRFILE_sbi_reboot	( ERRFILE_ARCH | ERRFILE_CORE | 0x00000000 )
+
 /** @} */
 
 #endif /* _BITS_ERRFILE_H */
diff --git a/src/arch/riscv/include/bits/reboot.h b/src/arch/riscv/include/bits/reboot.h
new file mode 100644
index 000000000..01272483b
--- /dev/null
+++ b/src/arch/riscv/include/bits/reboot.h
@@ -0,0 +1,14 @@
+#ifndef _BITS_REBOOT_H
+#define _BITS_REBOOT_H
+
+/** @file
+ *
+ * RISCV-specific reboot API implementations
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <ipxe/sbi_reboot.h>
+
+#endif /* _BITS_REBOOT_H */
diff --git a/src/arch/riscv/include/ipxe/sbi.h b/src/arch/riscv/include/ipxe/sbi.h
index 529f1d0c9..44685cc87 100644
--- a/src/arch/riscv/include/ipxe/sbi.h
+++ b/src/arch/riscv/include/ipxe/sbi.h
@@ -148,6 +148,16 @@ sbi_ecall_3 ( int eid, int fid, unsigned long p0, unsigned long p1,
 	return ret;
 }
 
+/** Convert an SBI error code to an iPXE status code */
+#define ESBI( error ) EPLATFORM ( EINFO_EPLATFORM, error )
+
+/** System reset extension */
+#define SBI_SRST SBI_EID ( 'S', 'R', 'S', 'T' )
+#define SBI_SRST_SYSTEM_RESET 0x00	/**< Reset system */
+#define SBI_RESET_SHUTDOWN 0x00000000	/**< Shutdown */
+#define SBI_RESET_COLD 0x00000001	/**< Cold reboot */
+#define SBI_RESET_WARM 0x00000002	/**< Warm reboot */
+
 /** Debug console extension */
 #define SBI_DBCN SBI_EID ( 'D', 'B', 'C', 'N' )
 #define SBI_DBCN_WRITE 0x00		/**< Console Write */
diff --git a/src/arch/riscv/include/ipxe/sbi_reboot.h b/src/arch/riscv/include/ipxe/sbi_reboot.h
new file mode 100644
index 000000000..e8d6e82bf
--- /dev/null
+++ b/src/arch/riscv/include/ipxe/sbi_reboot.h
@@ -0,0 +1,18 @@
+#ifndef _IPXE_BIOS_REBOOT_H
+#define _IPXE_BIOS_REBOOT_H
+
+/** @file
+ *
+ * Supervisor Binary Interface (SBI) reboot mechanism
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#ifdef REBOOT_SBI
+#define REBOOT_PREFIX_sbi
+#else
+#define REBOOT_PREFIX_sbi __sbi_
+#endif
+
+#endif /* _IPXE_BIOS_REBOOT_H */
diff --git a/src/arch/riscv/interface/sbi/sbi_reboot.c b/src/arch/riscv/interface/sbi/sbi_reboot.c
new file mode 100644
index 000000000..64365b0d3
--- /dev/null
+++ b/src/arch/riscv/interface/sbi/sbi_reboot.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2024 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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; either version 2 of the
+ * License, or any later version.
+ *
+ * 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * Supervisor Binary Interface (SBI) reboot mechanism
+ *
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <ipxe/sbi.h>
+#include <ipxe/reboot.h>
+
+/**
+ * Reboot system
+ *
+ * @v warm		Perform a warm reboot
+ */
+static void sbi_reboot ( int warm ) {
+	struct sbi_return ret;
+	int rc;
+
+	/* Reboot system */
+	ret = sbi_ecall_2 ( SBI_SRST, SBI_SRST_SYSTEM_RESET,
+			    ( warm ? SBI_RESET_WARM : SBI_RESET_COLD ), 0 );
+
+	/* Any return is an error */
+	rc = -ESBI ( ret.error );
+	DBGC ( SBI_SRST, "SBI %s reset failed: %s\n",
+	       ( warm ? "warm" : "cold" ), strerror ( rc ) );
+}
+
+/**
+ * Power off system
+ *
+ * @ret rc		Return status code
+ */
+static int sbi_poweroff ( void ) {
+	struct sbi_return ret;
+	int rc;
+
+	/* Shut down system */
+	ret = sbi_ecall_2 ( SBI_SRST, SBI_SRST_SYSTEM_RESET,
+			    SBI_RESET_SHUTDOWN, 0 );
+
+	/* Any return is an error */
+	rc = -ESBI ( ret.error );
+	DBGC ( SBI_SRST, "SBI shutdown failed: %s\n", strerror ( rc ) );
+	return rc;
+}
+
+PROVIDE_REBOOT ( sbi, reboot, sbi_reboot );
+PROVIDE_REBOOT ( sbi, poweroff, sbi_poweroff );