[U-Boot] [PATCH 3/4 v2] arm: Support new Xilinx Zynq platform
Michal Simek
monstr at monstr.eu
Thu Aug 16 08:30:29 CEST 2012
Add timer driver.
Signed-off-by: Michal Simek <monstr at monstr.eu>
---
v2: Move lowlevel_init.S from board to cpu folder
Remove XPSS prefix
Rename XSCUTIMER -> SCUTIMER
Keep timer in zynq folder till ARM custodian comments it.
---
arch/arm/cpu/armv7/zynq/Makefile | 52 +++++++++++
arch/arm/cpu/armv7/zynq/lowlevel_init.S | 27 ++++++
arch/arm/cpu/armv7/zynq/timer.c | 151 +++++++++++++++++++++++++++++++
3 files changed, 230 insertions(+), 0 deletions(-)
create mode 100644 arch/arm/cpu/armv7/zynq/Makefile
create mode 100644 arch/arm/cpu/armv7/zynq/lowlevel_init.S
create mode 100644 arch/arm/cpu/armv7/zynq/timer.c
diff --git a/arch/arm/cpu/armv7/zynq/Makefile b/arch/arm/cpu/armv7/zynq/Makefile
new file mode 100644
index 0000000..1d2d7e1
--- /dev/null
+++ b/arch/arm/cpu/armv7/zynq/Makefile
@@ -0,0 +1,52 @@
+#
+# (C) Copyright 2000-2003
+# Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+#
+# (C) Copyright 2008
+# Guennadi Liakhovetki, DENX Software Engineering, <lg at 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
+
+SOBJS-y := lowlevel_init.o
+COBJS-y := timer.o
+
+SOBJS := $(SOBJS-y)
+COBJS := $(COBJS-y)
+
+SRCS := $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
+
+all: $(obj).depend $(LIB)
+
+$(LIB): $(OBJS)
+ $(call cmd_link_o_target, $(OBJS))
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/arch/arm/cpu/armv7/zynq/lowlevel_init.S b/arch/arm/cpu/armv7/zynq/lowlevel_init.S
new file mode 100644
index 0000000..642eb18
--- /dev/null
+++ b/arch/arm/cpu/armv7/zynq/lowlevel_init.S
@@ -0,0 +1,27 @@
+/*
+ * (C) Copyright 2012 Michal Simek <monstr at monstr.eu>
+ *
+ * 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 <config.h>
+#include <linux/linkage.h>
+
+ENTRY(lowlevel_init)
+ mov pc, lr
+ENDPROC(lowlevel_init)
diff --git a/arch/arm/cpu/armv7/zynq/timer.c b/arch/arm/cpu/armv7/zynq/timer.c
new file mode 100644
index 0000000..0252220
--- /dev/null
+++ b/arch/arm/cpu/armv7/zynq/timer.c
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2012 Michal Simek <monstr at monstr.eu>
+ * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved.
+ *
+ * (C) Copyright 2008
+ * Guennadi Liakhovetki, DENX Software Engineering, <lg at denx.de>
+ *
+ * (C) Copyright 2004
+ * Philippe Robin, ARM Ltd. <philippe.robin at arm.com>
+ *
+ * (C) Copyright 2002-2004
+ * Gary Jennejohn, DENX Software Engineering, <gj at denx.de>
+ *
+ * (C) Copyright 2003
+ * Texas Instruments <www.ti.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger at sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu at 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 = 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)
+{
+ u32 val;
+
+ /* Load the timer counter register */
+ writel(0xFFFFFFFF, &timer_base->counter);
+
+ /* Start the A9Timer device */
+ val = readl(&timer_base->control);
+ /* Enable Auto reload mode */
+ val |= SCUTIMER_CONTROL_AUTO_RELOAD_MASK;
+ /* Clear prescaler control bits */
+ val &= ~SCUTIMER_CONTROL_PRESCALER_MASK;
+ /* Set prescaler value */
+ val |= (TIMER_PRESCALE << SCUTIMER_CONTROL_PRESCALER_SHIFT);
+ /* Enable the decrementer */
+ val |= SCUTIMER_CONTROL_ENABLE_MASK;
+ writel(val, &timer_base->control);
+
+ /* 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;
+}
--
1.7.0.4
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