patch-2.4.3 linux/include/asm-arm/arch-integrator/time.h
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- Lines: 141
- Date:
Fri Mar 2 18:38:39 2001
- Orig file:
v2.4.2/linux/include/asm-arm/arch-integrator/time.h
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.4.2/linux/include/asm-arm/arch-integrator/time.h linux/include/asm-arm/arch-integrator/time.h
@@ -0,0 +1,140 @@
+/*
+ * linux/include/asm-arm/arch-integrator/time.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <asm/system.h>
+#include <asm/leds.h>
+
+/*
+ * Where is the timer (VA)?
+ */
+#define TIMER0_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000000)
+#define TIMER1_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000100)
+#define TIMER2_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000200)
+#define VA_IC_BASE IO_ADDRESS(INTEGRATOR_IC_BASE)
+
+/*
+ * How long is the timer interval?
+ */
+#define TIMER_INTERVAL (TICKS_PER_uSEC * mSEC_10)
+#if TIMER_INTERVAL >= 0x100000
+#define TIMER_RELOAD (TIMER_INTERVAL >> 8) /* Divide by 256 */
+#define TIMER_CTRL 0x88 /* Enable, Clock / 256 */
+#define TICKS2USECS(x) (256 * (x) / TICKS_PER_uSEC)
+#elif TIMER_INTERVAL >= 0x10000
+#define TIMER_RELOAD (TIMER_INTERVAL >> 4) /* Divide by 16 */
+#define TIMER_CTRL 0x84 /* Enable, Clock / 16 */
+#define TICKS2USECS(x) (16 * (x) / TICKS_PER_uSEC)
+#else
+#define TIMER_RELOAD (TIMER_INTERVAL)
+#define TIMER_CTRL 0x80 /* Enable */
+#define TICKS2USECS(x) ((x) / TICKS_PER_uSEC)
+#endif
+
+/*
+ * What does it look like?
+ */
+typedef struct TimerStruct {
+ unsigned long TimerLoad;
+ unsigned long TimerValue;
+ unsigned long TimerControl;
+ unsigned long TimerClear;
+} TimerStruct_t;
+
+extern unsigned long (*gettimeoffset)(void);
+
+/*
+ * Returns number of ms since last clock interrupt. Note that interrupts
+ * will have been disabled by do_gettimeoffset()
+ */
+static unsigned long integrator_gettimeoffset(void)
+{
+ volatile TimerStruct_t *timer1 = (TimerStruct_t *)TIMER1_VA_BASE;
+ unsigned long ticks1, ticks2, status;
+
+ /*
+ * Get the current number of ticks. Note that there is a race
+ * condition between us reading the timer and checking for
+ * an interrupt. We get around this by ensuring that the
+ * counter has not reloaded between our two reads.
+ */
+ ticks2 = timer1->TimerValue & 0xffff;
+ do {
+ ticks1 = ticks2;
+ status = __raw_readl(VA_IC_BASE + IRQ_RAW_STATUS);
+ ticks2 = timer1->TimerValue & 0xffff;
+ } while (ticks2 > ticks1);
+
+ /*
+ * Number of ticks since last interrupt.
+ */
+ ticks1 = TIMER_RELOAD - ticks2;
+
+ /*
+ * Interrupt pending? If so, we've reloaded once already.
+ */
+ if (status & IRQMASK_TIMERINT1)
+ ticks1 += TIMER_RELOAD;
+
+ /*
+ * Convert the ticks to usecs
+ */
+ return TICKS2USECS(ticks1);
+}
+
+/*
+ * IRQ handler for the timer
+ */
+static void integrator_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ volatile TimerStruct_t *timer1 = (volatile TimerStruct_t *)TIMER1_VA_BASE;
+
+ // ...clear the interrupt
+ timer1->TimerClear = 1;
+
+ do_leds();
+ do_timer(regs);
+ do_profile(regs);
+}
+
+/*
+ * Set up timer interrupt, and return the current time in seconds.
+ */
+extern __inline__ void setup_timer(void)
+{
+ volatile TimerStruct_t *timer0 = (volatile TimerStruct_t *)TIMER0_VA_BASE;
+ volatile TimerStruct_t *timer1 = (volatile TimerStruct_t *)TIMER1_VA_BASE;
+ volatile TimerStruct_t *timer2 = (volatile TimerStruct_t *)TIMER2_VA_BASE;
+
+ timer_irq.handler = integrator_timer_interrupt;
+
+ /*
+ * Initialise to a known state (all timers off)
+ */
+ timer0->TimerControl = 0;
+ timer1->TimerControl = 0;
+ timer2->TimerControl = 0;
+
+ timer1->TimerLoad = TIMER_RELOAD;
+ timer1->TimerValue = TIMER_RELOAD;
+ timer1->TimerControl = TIMER_CTRL | 0x40; /* periodic */
+
+ /*
+ * Make irqs happen for the system timer
+ */
+ setup_arm_irq(IRQ_TIMERINT1, &timer_irq);
+ gettimeoffset = integrator_gettimeoffset;
+}
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