nds32/ag101: cpu and init funcs of SoC ag101

SoC ag101 is the first chip using NDS32 N1213 cpu core.
Add header file of device offset support for SoC ag101.
Add main function of SoC ag101 based on NDS32 n1213 core.
Add lowlevel_init.S and other periphal related code.

This version of lowlevel_init.S also replace hardcode value
by MARCO defines from the GPL version andesboot for better
code quality.

Signed-off-by: Macpaul Lin <macpaul@andestech.com>

1 files changed, 205 insertions, 0 deletions

diff --git a/arch/nds32/cpu/n1213/ag101/timer.c b/arch/nds32/cpu/n1213/ag101/timer.c
new file mode 100644
index 0000000..c099c33
--- /dev/null
+++ b/arch/nds32/cpu/n1213/ag101/timer.c
@@ -0,0 +1,205 @@
+/*
+ * (C) Copyright 2009 Faraday Technology
+ * Po-Yu Chuang <ratbert@faraday-tech.com>
+ *
+ * Copyright (C) 2011 Andes Technology Corporation
+ * Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com>
+ * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <faraday/fttmr010.h>
+
+static ulong timestamp;
+static ulong lastdec;
+
+int timer_init(void)
+{
+	static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+	unsigned int cr;
+
+	debug("%s()\n", __func__);
+
+	/* disable timers */
+	writel(0, &tmr->cr);
+
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	/* use 32768Hz oscillator for RTC, WDT, TIMER */
+	ftpmu010_32768osc_enable();
+#endif
+
+	/* setup timer */
+	writel(TIMER_LOAD_VAL, &tmr->timer3_load);
+	writel(TIMER_LOAD_VAL, &tmr->timer3_counter);
+	writel(0, &tmr->timer3_match1);
+	writel(0, &tmr->timer3_match2);
+
+	/* we don't want timer to issue interrupts */
+	writel(FTTMR010_TM3_MATCH1 |
+	       FTTMR010_TM3_MATCH2 |
+	       FTTMR010_TM3_OVERFLOW,
+	       &tmr->interrupt_mask);
+
+	cr = readl(&tmr->cr);
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	cr |= FTTMR010_TM3_CLOCK;	/* use external clock */
+#endif
+	cr |= FTTMR010_TM3_ENABLE;
+	writel(cr, &tmr->cr);
+
+	/* init the timestamp and lastdec value */
+	reset_timer_masked();
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+
+/*
+ * reset time
+ */
+void reset_timer_masked(void)
+{
+	static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+	/* capure current decrementer value time */
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	lastdec = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ);
+#else
+	lastdec = readl(&tmr->timer3_counter) / (CONFIG_SYS_CLK_FREQ / 2);
+#endif
+	timestamp = 0;		/* start "advancing" time stamp from 0 */
+
+	debug("%s(): lastdec = %lx\n", __func__, lastdec);
+}
+
+void reset_timer(void)
+{
+	debug("%s()\n", __func__);
+	reset_timer_masked();
+}
+
+/*
+ * return timer ticks
+ */
+ulong get_timer_masked(void)
+{
+	static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+	/* current tick value */
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	ulong now = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ);
+#else
+	ulong now = readl(&tmr->timer3_counter) / \
+			(CONFIG_SYS_CLK_FREQ / 2 / 1024);
+#endif
+
+	debug("%s(): now = %lx, lastdec = %lx\n", __func__, now, lastdec);
+
+	if (lastdec >= now) {
+		/*
+		 * normal mode (non roll)
+		 * move stamp fordward with absoulte diff ticks
+		 */
+		timestamp += lastdec - now;
+	} 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;
+
+	debug("%s() returns %lx\n", __func__, timestamp);
+
+	return timestamp;
+}
+
+/*
+ * return difference between timer ticks and base
+ */
+ulong get_timer(ulong base)
+{
+	debug("%s(%lx)\n", __func__, base);
+	return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+	debug("%s(%lx)\n", __func__, t);
+	timestamp = t;
+}
+
+/* delay x useconds AND preserve advance timestamp value */
+void __udelay(unsigned long usec)
+{
+	static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	long tmo = usec * (TIMER_CLOCK / 1000) / 1000;
+#else
+	long tmo = usec * ((CONFIG_SYS_CLK_FREQ / 2) / 1000) / 1000;
+#endif
+	unsigned long now, last = readl(&tmr->timer3_counter);
+
+	debug("%s(%lu)\n", __func__, usec);
+	while (tmo > 0) {
+		now = readl(&tmr->timer3_counter);
+		if (now > last) /* count down timer overflow */
+			tmo -= TIMER_LOAD_VAL + last - now;
+		else
+			tmo -= last - now;
+		last = now;
+	}
+}
+
+/*
+ * 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)
+{
+	debug("%s()\n", __func__);
+	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)
+{
+	debug("%s()\n", __func__);
+#ifdef CONFIG_FTTMR010_EXT_CLK
+	return CONFIG_SYS_HZ;
+#else
+	return CONFIG_SYS_CLK_FREQ;
+#endif
+}