aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/jazz/reset.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/jazz/reset.c')
-rw-r--r--arch/mips/jazz/reset.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/mips/jazz/reset.c b/arch/mips/jazz/reset.c
new file mode 100644
index 000000000000..2a9754750bc8
--- /dev/null
+++ b/arch/mips/jazz/reset.c
@@ -0,0 +1,69 @@
+/*
+ * Reset a Jazz machine.
+ *
+ * We don't trust the firmware so we do it the classic way by poking and
+ * stabbing at the keyboard controller ...
+ */
+#include <linux/jiffies.h>
+#include <asm/jazz.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/reboot.h>
+#include <asm/delay.h>
+
+#define KBD_STAT_IBF 0x02 /* Keyboard input buffer full */
+
+static void jazz_write_output(unsigned char val)
+{
+ int status;
+
+ do {
+ status = jazz_kh->command;
+ } while (status & KBD_STAT_IBF);
+ jazz_kh->data = val;
+}
+
+static void jazz_write_command(unsigned char val)
+{
+ int status;
+
+ do {
+ status = jazz_kh->command;
+ } while (status & KBD_STAT_IBF);
+ jazz_kh->command = val;
+}
+
+static unsigned char jazz_read_status(void)
+{
+ return jazz_kh->command;
+}
+
+static inline void kb_wait(void)
+{
+ unsigned long start = jiffies;
+ unsigned long timeout = start + HZ/2;
+
+ do {
+ if (! (jazz_read_status() & 0x02))
+ return;
+ } while (time_before_eq(jiffies, timeout));
+}
+
+void jazz_machine_restart(char *command)
+{
+ while(1) {
+ kb_wait();
+ jazz_write_command (0xd1);
+ kb_wait();
+ jazz_write_output (0x00);
+ }
+}
+
+void jazz_machine_halt(void)
+{
+}
+
+void jazz_machine_power_off(void)
+{
+ /* Jazz machines don't have a software power switch */
+}