1/* 2 * Reset a Jazz machine. 3 * 4 * We don't trust the firmware so we do it the classic way by poking and 5 * stabbing at the keyboard controller ... 6 */ 7#include <linux/jiffies.h> 8#include <asm/jazz.h> 9 10#define KBD_STAT_IBF 0x02 /* Keyboard input buffer full */ 11 12static void jazz_write_output(unsigned char val) 13{ 14 int status; 15 16 do { 17 status = jazz_kh->command; 18 } while (status & KBD_STAT_IBF); 19 jazz_kh->data = val; 20} 21 22static void jazz_write_command(unsigned char val) 23{ 24 int status; 25 26 do { 27 status = jazz_kh->command; 28 } while (status & KBD_STAT_IBF); 29 jazz_kh->command = val; 30} 31 32static unsigned char jazz_read_status(void) 33{ 34 return jazz_kh->command; 35} 36 37static inline void kb_wait(void) 38{ 39 unsigned long start = jiffies; 40 unsigned long timeout = start + HZ/2; 41 42 do { 43 if (! (jazz_read_status() & 0x02)) 44 return; 45 } while (time_before_eq(jiffies, timeout)); 46} 47 48void jazz_machine_restart(char *command) 49{ 50 while(1) { 51 kb_wait(); 52 jazz_write_command(0xd1); 53 kb_wait(); 54 jazz_write_output(0x00); 55 } 56} 57