8680 Time of Day clock error

*** 17,26 ****
--- 17,27 ----
   * information: Portions Copyright [yyyy] [name of copyright owner]
   *
   * CDDL HEADER END
   */
  /*
+  * Copyright 2018 Gary Mills
   * Copyright 2012 Nexenta Systems, Inc.  All rights reserved.
   */
  /*
   * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
*** 44,53 ****
--- 45,55 ----
  #include <sys/archsystm.h>
  #include <sys/sysmacros.h>
  #include <sys/lockstat.h>
  #include <sys/stat.h>
  #include <sys/sunddi.h>
+ #include <sys/ddi.h>
  
  #include <sys/acpi/acpi.h>
  #include <sys/acpica.h>
  
  static int todpc_rtcget(unsigned char *buf);
*** 328,338 ****
  
  /*
   * Routine to read contents of real time clock to the specified buffer.
   * Returns ENXIO if clock not valid, or EAGAIN if clock data cannot be read
   * else 0.
!  * The routine will busy wait for the Update-In-Progress flag to clear.
   * On completion of the reads the Seconds register is re-read and the
   * UIP flag is rechecked to confirm that an clock update did not occur
   * during the accesses.  Routine will error exit after 256 attempts.
   * (See bugid 1158298.)
   * Routine returns RTC_NREG (which is 15) bytes of data, as given in the
--- 330,342 ----
  
  /*
   * Routine to read contents of real time clock to the specified buffer.
   * Returns ENXIO if clock not valid, or EAGAIN if clock data cannot be read
   * else 0.
!  * Some RTC hardware is very slow at asserting the validity flag on
!  * startup.  The routine will busy wait for the RTC to become valid.
!  * The routine will also busy wait for the Update-In-Progress flag to clear.
   * On completion of the reads the Seconds register is re-read and the
   * UIP flag is rechecked to confirm that an clock update did not occur
   * during the accesses.  Routine will error exit after 256 attempts.
   * (See bugid 1158298.)
   * Routine returns RTC_NREG (which is 15) bytes of data, as given in the
*** 342,352 ****
  static int
  todpc_rtcget(unsigned char *buf)
  {
          unsigned char   reg;
          int             i;
!         int             retries = 256;
          unsigned char   *rawp;
          unsigned char   century = RTC_CENTURY;
          unsigned char   day_alrm;
          unsigned char   mon_alrm;
  
--- 346,357 ----
  static int
  todpc_rtcget(unsigned char *buf)
  {
          unsigned char   reg;
          int             i;
!         int             uip_try = 256;
!         int             vrt_try = 512;
          unsigned char   *rawp;
          unsigned char   century = RTC_CENTURY;
          unsigned char   day_alrm;
          unsigned char   mon_alrm;
  
*** 356,372 ****
          mon_alrm = pc_rtc_offset.mon_alrm;
          if (pc_rtc_offset.century != 0) {
                  century = pc_rtc_offset.century;
          }
  
          outb(RTC_ADDR, RTC_D);          /* check if clock valid */
          reg = inb(RTC_DATA);
!         if ((reg & RTC_VRT) == 0)
!                 return (ENXIO);
  
  checkuip:
!         if (retries-- < 0)
                  return (EAGAIN);
          outb(RTC_ADDR, RTC_A);          /* check if update in progress */
          reg = inb(RTC_DATA);
          if (reg & RTC_UIP) {
                  tenmicrosec();
--- 361,383 ----
          mon_alrm = pc_rtc_offset.mon_alrm;
          if (pc_rtc_offset.century != 0) {
                  century = pc_rtc_offset.century;
          }
  
+         for (;;) {
+                 if (vrt_try-- < 0)
+                         return (ENXIO);
                  outb(RTC_ADDR, RTC_D);          /* check if clock valid */
                  reg = inb(RTC_DATA);
!                 if ((reg & RTC_VRT) != 0)
!                         break;
!                 drv_usecwait(5000);             /* Delay for 5000 us */
!         }
  
+ 
  checkuip:
!         if (uip_try-- < 0)
                  return (EAGAIN);
          outb(RTC_ADDR, RTC_A);          /* check if update in progress */
          reg = inb(RTC_DATA);
          if (reg & RTC_UIP) {
                  tenmicrosec();