arm: Support new Xilinx Zynq platform

Add timer driver.

Signed-off-by: Michal Simek <monstr@monstr.eu>
CC: Joe Hershberger <joe.hershberger@gmail.com>
CC: Marek Vasut <marex@denx.de>
Acked-by: Marek Vasut <marex@denx.de>

arch/arm/cpu/armv7/zynq/Makefile

+#
+# (C) Copyright 2000-2003
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# (C) Copyright 2008
+# Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
+#
+# 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 $(TOPDIR)/config.mk
+
+LIB	= $(obj)lib$(SOC).o
+
+COBJS-y	:= timer.o
+COBJS-y	+= cpu.o
+
+COBJS	:= $(COBJS-y)
+
+SRCS	:= $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+
+all:	$(obj).depend $(LIB)
+
+$(LIB): $(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################

arch/arm/cpu/armv7/zynq/cpu.c

+/*
+ * Copyright (C) 2012 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2012 Xilinx, Inc. All rights reserved.
+ *
+ * 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>
+
+inline void lowlevel_init(void) {}
+
+void reset_cpu(ulong addr)
+{
+	while (1)
+		;
+}

arch/arm/cpu/armv7/zynq/timer.c

+/*
+ * Copyright (C) 2012 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved.
+ *
+ * (C) Copyright 2008
+ * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
+ *
+ * (C) Copyright 2004
+ * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
+ *
+ * (C) Copyright 2002-2004
+ * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
+ *
+ * (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>
+ *
+ * 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 <div64.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct scu_timer {
+	u32 load; /* Timer Load Register */
+	u32 counter; /* Timer Counter Register */
+	u32 control; /* Timer Control Register */
+};
+
+static struct scu_timer *timer_base =
+			      (struct scu_timer *) CONFIG_SCUTIMER_BASEADDR;
+
+#define SCUTIMER_CONTROL_PRESCALER_MASK	0x0000FF00 /* Prescaler */
+#define SCUTIMER_CONTROL_PRESCALER_SHIFT	8
+#define SCUTIMER_CONTROL_AUTO_RELOAD_MASK	0x00000002 /* Auto-reload */
+#define SCUTIMER_CONTROL_ENABLE_MASK		0x00000001 /* Timer enable */
+
+#define TIMER_LOAD_VAL 0xFFFFFFFF
+#define TIMER_PRESCALE 255
+#define TIMER_TICK_HZ  (CONFIG_CPU_FREQ_HZ / 2 / TIMER_PRESCALE)
+
+int timer_init(void)
+{
+	const u32 emask = SCUTIMER_CONTROL_AUTO_RELOAD_MASK |
+			(TIMER_PRESCALE << SCUTIMER_CONTROL_PRESCALER_SHIFT) |
+			SCUTIMER_CONTROL_ENABLE_MASK;
+
+	/* Load the timer counter register */
+	writel(0xFFFFFFFF, &timer_base->counter);
+
+	/*
+	 * Start the A9Timer device
+	 * Enable Auto reload mode, Clear prescaler control bits
+	 * Set prescaler value, Enable the decrementer
+	 */
+	clrsetbits_le32(&timer_base->control, SCUTIMER_CONTROL_PRESCALER_MASK,
+								emask);
+
+	/* Reset time */
+	gd->lastinc = readl(&timer_base->counter) /
+					(TIMER_TICK_HZ / CONFIG_SYS_HZ);
+	gd->tbl = 0;
+
+	return 0;
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+ulong get_timer_masked(void)
+{
+	ulong now;
+
+	now = readl(&timer_base->counter) / (TIMER_TICK_HZ / CONFIG_SYS_HZ);
+
+	if (gd->lastinc >= now) {
+		/* Normal mode */
+		gd->tbl += gd->lastinc - now;
+	} else {
+		/* We have an overflow ... */
+		gd->tbl += gd->lastinc + TIMER_LOAD_VAL - now;
+	}
+	gd->lastinc = now;
+
+	return gd->tbl;
+}
+
+void __udelay(unsigned long usec)
+{
+	unsigned long long tmp;
+	ulong tmo;
+
+	tmo = usec / (1000000 / CONFIG_SYS_HZ);
+	tmp = get_ticks() + tmo; /* Get current timestamp */
+
+	while (get_ticks() < tmp) { /* Loop till event */
+		 /* NOP */;
+	}
+}
+
+/* Timer without interrupts */
+ulong get_timer(ulong base)
+{
+	return get_timer_masked() - base;
+}
+
+/*
+ * 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)
+{
+	return CONFIG_SYS_HZ;
+}