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Diffstat (limited to 'arch/x86/lib/pcat_timer.c')
-rw-r--r--arch/x86/lib/pcat_timer.c69
1 files changed, 3 insertions, 66 deletions
diff --git a/arch/x86/lib/pcat_timer.c b/arch/x86/lib/pcat_timer.c
index b0b6637f3a..1ca3eb9e91 100644
--- a/arch/x86/lib/pcat_timer.c
+++ b/arch/x86/lib/pcat_timer.c
@@ -24,83 +24,20 @@
#include <common.h>
#include <asm/io.h>
#include <asm/i8254.h>
-#include <asm/ibmpc.h>
-#include <asm/interrupt.h>
-#define TIMER0_VALUE 0x04aa /* 1kHz 1.9318MHz / 1000 */
#define TIMER2_VALUE 0x0a8e /* 440Hz */
-static int timer_init_done;
-
-int timer_init(void)
+int pcat_timer_init(void)
{
- /* initialize timer 0 and 2
- *
- * Timer 0 is used to increment system_tick 1000 times/sec
- * Timer 1 was used for DRAM refresh in early PC's
- * Timer 2 is used to drive the speaker
+ /*
+ * initialize 2, used to drive the speaker
* (to start a beep: write 3 to port 0x61,
* to stop it again: write 0)
*/
- outb(PIT_CMD_CTR0 | PIT_CMD_BOTH | PIT_CMD_MODE2,
- PIT_BASE + PIT_COMMAND);
- outb(TIMER0_VALUE & 0xff, PIT_BASE + PIT_T0);
- outb(TIMER0_VALUE >> 8, PIT_BASE + PIT_T0);
-
outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3,
PIT_BASE + PIT_COMMAND);
outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2);
outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2);
- irq_install_handler(0, timer_isr, NULL);
- unmask_irq(0);
-
- timer_init_done = 1;
-
return 0;
}
-
-static u16 read_pit(void)
-{
- u8 low;
-
- outb(PIT_CMD_LATCH, PIT_BASE + PIT_COMMAND);
- low = inb(PIT_BASE + PIT_T0);
-
- return (inb(PIT_BASE + PIT_T0) << 8) | low;
-}
-
-/* this is not very exact */
-void __udelay(unsigned long usec)
-{
- int counter;
- int wraps;
-
- if (timer_init_done) {
- counter = read_pit();
- wraps = usec / 1000;
- usec = usec % 1000;
-
- usec *= 1194;
- usec /= 1000;
- usec += counter;
-
- while (usec > 1194) {
- usec -= 1194;
- wraps++;
- }
-
- while (1) {
- int new_count = read_pit();
-
- if (((new_count < usec) && !wraps) || wraps < 0)
- break;
-
- if (new_count > counter)
- wraps--;
-
- counter = new_count;
- }
- }
-
-}