reset.c 963 B

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748
  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * linux/arch/mips/sni/process.c
  4. *
  5. * Reset a SNI machine.
  6. */
  7. #include <linux/delay.h>
  8. #include <asm/io.h>
  9. #include <asm/reboot.h>
  10. #include <asm/sni.h>
  11. /*
  12. * This routine reboots the machine by asking the keyboard
  13. * controller to pulse the reset-line low. We try that for a while,
  14. * and if it doesn't work, we do some other stupid things.
  15. */
  16. static inline void kb_wait(void)
  17. {
  18. int i;
  19. for (i = 0; i < 0x10000; i++)
  20. if ((inb_p(0x64) & 0x02) == 0)
  21. break;
  22. }
  23. /* XXX This ends up at the ARC firmware prompt ... */
  24. void sni_machine_restart(char *command)
  25. {
  26. int i;
  27. /* This does a normal via the keyboard controller like a PC.
  28. We can do that easier ... */
  29. local_irq_disable();
  30. for (;;) {
  31. for (i = 0; i < 100; i++) {
  32. kb_wait();
  33. udelay(50);
  34. outb_p(0xfe, 0x64); /* pulse reset low */
  35. udelay(50);
  36. }
  37. }
  38. }
  39. void sni_machine_power_off(void)
  40. {
  41. *(volatile unsigned char *)PCIMT_CSWCSM = 0xfd;
  42. }