--- zzzz-none-000/linux-2.6.19.2/Documentation/mips/time.README	2007-01-10 19:10:37.000000000 +0000
+++ davinci-8020-5504/linux-2.6.19.2/Documentation/mips/time.README	2007-01-11 07:38:19.000000000 +0000
@@ -38,14 +38,19 @@
 
   a) Implements functions required by Linux common code:
 	time_init
+	do_gettimeofday
+	do_settimeofday
 
   b) provides an abstraction of RTC and null RTC implementation as default.
 	extern unsigned long (*rtc_get_time)(void);
 	extern int (*rtc_set_time)(unsigned long);
 
-  c) high-level and low-level timer interrupt routines where the timer
-     interrupt source  may or may not be the CPU timer.  The high-level
-     routine is dispatched through do_IRQ() while the low-level is
+  c) a set of gettimeoffset functions for different CPUs and different
+     needs.
+
+  d) high-level and low-level timer interrupt routines where the timer 
+     interrupt source  may or may not be the CPU timer.  The high-level 
+     routine is dispatched through do_IRQ() while the low-level is 
      dispatched in assemably code (usually int-handler.S)
 
 
@@ -68,7 +73,8 @@
   c) (optional) board-specific RTC routines.
 
   d) (optional) mips_hpt_frequency - It must be definied if the board
-     is using CPU counter for timer interrupt.
+     is using CPU counter for timer interrupt or it is using fixed rate
+     gettimeoffset().
 
 
 PORTING GUIDE
@@ -83,6 +89,16 @@
      If the answer is no, you need a timer to provide the timer interrupt
      at 100 HZ speed.
 
+     You cannot use the fast gettimeoffset functions, i.e.,
+
+	unsigned long fixed_rate_gettimeoffset(void);
+	unsigned long calibrate_div32_gettimeoffset(void);
+	unsigned long calibrate_div64_gettimeoffset(void);
+
+    You can use null_gettimeoffset() will gives the same time resolution as
+    jiffy.  Or you can implement your own gettimeoffset (probably based on 
+    some ad hoc hardware on your machine.)
+
   c) The following sub steps assume your CPU has counter register.
      Do you plan to use the CPU counter register as the timer interrupt
      or use an exnternal timer?
@@ -107,8 +123,8 @@
   board_time_init() -
   	a) (optional) set up RTC routines,
         b) (optional) calibrate and set the mips_hpt_frequency
- 	    (only needed if you intended to use cpu counter as timer interrupt
- 	     source)
+ 	    (only needed if you intended to use fixed_rate_gettimeoffset
+ 	     or use cpu counter as timer interrupt source)
 
   plat_timer_setup() -
  	a) (optional) over-write any choices made above by time_init().
@@ -138,8 +154,8 @@
 For example, you may define your own timer interrupt routine, which does
 some of its own processing and then calls timer_interrupt().
 
-You can also over-ride any of the built-in functions (RTC routines
-and/or timer interrupt routine).
+You can also over-ride any of the built-in functions (gettimeoffset,
+RTC routines and/or timer interrupt routine).
 
 
 PORTING NOTES FOR SMP
@@ -171,3 +187,10 @@
 
 	You can also do the low-level version of those interrupt routines,
 	following similar dispatching routes described above.
+
+Note about do_gettimeoffset():
+
+  It is very likely the CPU counter registers are not sync'ed up in a SMP box.
+  Therefore you cannot really use the many of the existing routines that
+  are based on CPU counter.  You should wirte your own gettimeoffset rouinte
+  if you want intra-jiffy resolution.