patch-2.4.3 linux/include/asm-arm/arch-integrator/time.h

• 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;
+}