Changeset 9a5b556 in mainline for kernel/arch/sparc64/src/drivers/tick.c

Timestamp:

2006-09-12T13:03:55Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

6eabb6e6

Parents:

7bb6b06

Message:

sparc64 work:

• find a CPU node and read its clock_frequency attribute
• implement asm_delay_loop()
• set TICK_COMPARE register according to processor frequency
• small improvements at random places

OpenFirmware work:

• two new functions for walking the device tree

Generic boot loader work:

• added basic string functions

Usual pile of indentation and formatting fixes.

File:

• kernel/arch/sparc64/src/drivers/tick.c (modified) (4 diffs)

kernel/arch/sparc64/src/drivers/tick.c

@@ -37 +37 @@
 #include <arch/asm.h>
 #include <arch/register.h>
+#include <typedefs.h>
+#include <arch/cpu.h>
+#include <arch/boot/boot.h>
+#include <time/clock.h>
+#include <arch.h>
 #include <debug.h>
-#include <time/clock.h>
-#include <typedefs.h>
+
+#define TICK_RESTART_TIME       50      /* Worst case estimate. */
 
 /** Initialize tick interrupt. */
@@ -48 +53 @@
         interrupt_register(14, "tick_int", tick_interrupt);
         compare.int_dis = false;
-        compare.tick_cmpr = TICK_DELTA;
+        compare.tick_cmpr = bootinfo.processor.clock_frequency/HZ;
         tick_compare_write(compare.value);
         tick_write(0);
@@ -61 +66 @@
 {
         softint_reg_t softint, clear;
+        uint64_t next, compare, start, stop;
         
         softint.value = softint_read();
@@ -84 +90 @@
          * Restart counter.
          */
-        tick_write(0);
+        compare = CPU->arch.clock_frequency/HZ;
+        start = tick_read();
+        next = start - compare;
+        while (next >= compare - TICK_RESTART_TIME) {
+                next -= compare;
+                CPU->missed_clock_ticks++;
+        }
+        stop = tick_read();
+        tick_write(next + (stop - start));
         
         clock();