Apply SoC concept to arm926ejs CPUs, i.e. move the SoC specific timer and

cpu_reset code from cpu/$(CPU) into the new cpu/$(CPU)/$(SOC) directories
Patch by Andreas Engel, 13 Mar 2006

1 files changed, 175 insertions, 0 deletions

diff --git a/cpu/arm926ejs/versatile/timer.c b/cpu/arm926ejs/versatile/timer.c
new file mode 100644
index 0000000..32872d2
--- /dev/null
+++ b/cpu/arm926ejs/versatile/timer.c
@@ -0,0 +1,175 @@
+/*
+ * (C) Copyright 2003
+ * Texas Instruments <www.ti.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002-2004
+ * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
+ *
+ * (C) Copyright 2004
+ * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <common.h>
+#include <arm926ejs.h>
+
+#define TIMER_LOAD_VAL 0xffffffff
+
+/* macro to read the 32 bit timer */
+#define READ_TIMER (*(volatile ulong *)(CFG_TIMERBASE+4))
+
+static ulong timestamp;
+static ulong lastdec;
+
+/* nothing really to do with interrupts, just starts up a counter. */
+int timer_init (void)
+{
+	*(volatile ulong *)(CFG_TIMERBASE + 0) = CFG_TIMER_RELOAD;	/* TimerLoad */
+	*(volatile ulong *)(CFG_TIMERBASE + 4) = CFG_TIMER_RELOAD;	/* TimerValue */
+	*(volatile ulong *)(CFG_TIMERBASE + 8) = 0x8C;
+
+	/* init the timestamp and lastdec value */
+	reset_timer_masked();
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+
+void reset_timer (void)
+{
+	reset_timer_masked ();
+}
+
+ulong get_timer (ulong base)
+{
+	return get_timer_masked () - base;
+}
+
+void set_timer (ulong t)
+{
+	timestamp = t;
+}
+
+/* delay x useconds AND perserve advance timstamp value */
+void udelay (unsigned long usec)
+{
+	ulong tmo, tmp;
+
+	if(usec >= 1000){		/* if "big" number, spread normalization to seconds */
+		tmo = usec / 1000;	/* start to normalize for usec to ticks per sec */
+		tmo *= CFG_HZ;		/* find number of "ticks" to wait to achieve target */
+		tmo /= 1000;		/* finish normalize. */
+	}else{				/* else small number, don't kill it prior to HZ multiply */
+		tmo = usec * CFG_HZ;
+		tmo /= (1000*1000);
+	}
+
+	tmp = get_timer (0);		/* get current timestamp */
+	if( (tmo + tmp + 1) < tmp )	/* if setting this fordward will roll time stamp */
+		reset_timer_masked ();	/* reset "advancing" timestamp to 0, set lastdec value */
+	else
+		tmo += tmp;		/* else, set advancing stamp wake up time */
+
+	while (get_timer_masked () < tmo)/* loop till event */
+		/*NOP*/;
+}
+
+void reset_timer_masked (void)
+{
+	/* reset time */
+	lastdec = READ_TIMER;  /* capure current decrementer value time */
+	timestamp = 0;	       /* start "advancing" time stamp from 0 */
+}
+
+ulong get_timer_masked (void)
+{
+	ulong now = READ_TIMER;		/* current tick value */
+
+	if (lastdec >= now) {		/* normal mode (non roll) */
+		/* normal mode */
+		timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
+	} else {			/* we have overflow of the count down timer */
+		/* nts = ts + ld + (TLV - now)
+		 * ts=old stamp, ld=time that passed before passing through -1
+		 * (TLV-now) amount of time after passing though -1
+		 * nts = new "advancing time stamp"...it could also roll and cause problems.
+		 */
+		timestamp += lastdec + TIMER_LOAD_VAL - now;
+	}
+	lastdec = now;
+
+	return timestamp;
+}
+
+/* waits specified delay value and resets timestamp */
+void udelay_masked (unsigned long usec)
+{
+	ulong tmo;
+	ulong endtime;
+	signed long diff;
+
+	if (usec >= 1000) {		/* if "big" number, spread normalization to seconds */
+		tmo = usec / 1000;	/* start to normalize for usec to ticks per sec */
+		tmo *= CFG_HZ;		/* find number of "ticks" to wait to achieve target */
+		tmo /= 1000;		/* finish normalize. */
+	} else {			/* else small number, don't kill it prior to HZ multiply */
+		tmo = usec * CFG_HZ;
+		tmo /= (1000*1000);
+	}
+
+	endtime = get_timer_masked () + tmo;
+
+	do {
+		ulong now = get_timer_masked ();
+		diff = endtime - now;
+	} while (diff >= 0);
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+	return get_timer(0);
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk (void)
+{
+	ulong tbclk;
+
+	tbclk = CFG_HZ;
+	return tbclk;
+}