1 files changed, 48 insertions, 0 deletions

diff --git a/arch/mips/sni/reset.c b/arch/mips/sni/reset.c
new file mode 100644
index 000000000..66f963d8d
--- /dev/null
+++ b/arch/mips/sni/reset.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/arch/mips/sni/process.c
+ *
+ *  Reset a SNI machine.
+ */
+#include <linux/delay.h>
+
+#include <asm/io.h>
+#include <asm/reboot.h>
+#include <asm/sni.h>
+
+/*
+ * This routine reboots the machine by asking the keyboard
+ * controller to pulse the reset-line low. We try that for a while,
+ * and if it doesn't work, we do some other stupid things.
+ */
+static inline void kb_wait(void)
+{
+        int i;
+
+        for (i = 0; i < 0x10000; i++)
+                if ((inb_p(0x64) & 0x02) == 0)
+                        break;
+}
+
+/* XXX This ends up at the ARC firmware prompt ...  */
+void sni_machine_restart(char *command)
+{
+        int i;
+
+        /* This does a normal via the keyboard controller like a PC.
+           We can do that easier ...  */
+        local_irq_disable();
+        for (;;) {
+                for (i = 0; i < 100; i++) {
+                        kb_wait();
+                        udelay(50);
+                        outb_p(0xfe, 0x64);      /* pulse reset low */
+                        udelay(50);
+                }
+        }
+}
+
+void sni_machine_power_off(void)
+{
+        *(volatile unsigned char *)PCIMT_CSWCSM = 0xfd;
+}