[U-Boot] [PATCH 4/5] arm: add support for arch timer

[Murali Karicheri]

This patch add basic support for the architecture timer found on recent
ARMv7 based SoCs.

Signed-off-by: Vitaly Andrianov <vitalya at ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2 at ti.com>
---
 arch/arm/lib/Makefile     |    1 +
 arch/arm/lib/arch_timer.c |   69 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 arch/arm/lib/arch_timer.c

diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 321997c..58d58f8 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -42,6 +42,7 @@ obj-$(CONFIG_USE_ARCH_MEMCPY) += memcpy.o
 else
 obj-$(CONFIG_SPL_FRAMEWORK) += spl.o
 endif
+COBJS-$(CONFIG_SYS_ARCH_TIMER) += arch_timer.o
 
 ifdef CONFIG_ARM64
 obj-y	+= interrupts_64.o
diff --git a/arch/arm/lib/arch_timer.c b/arch/arm/lib/arch_timer.c
new file mode 100644
index 0000000..6ffa650
--- /dev/null
+++ b/arch/arm/lib/arch_timer.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2012, Texas Instruments <www.ti.com>
+ *
+ * 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 <div64.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int timer_init(void)
+{
+	gd->arch.tbl = 0;
+	gd->arch.tbu = 0;
+
+	gd->arch.timer_rate_hz = CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ;
+
+	return 0;
+}
+
+unsigned long long get_ticks(void)
+{
+	ulong nowl, nowu;
+
+	asm volatile("mrrc p15, 0, %0, %1, c14" : "=r" (nowl), "=r" (nowu));
+
+	gd->arch.tbl = nowl;
+	gd->arch.tbu = nowu;
+
+	return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
+}
+
+
+ulong get_timer(ulong base)
+{
+	return lldiv(get_ticks(), gd->arch.timer_rate_hz) - base;
+}
+
+void __udelay(unsigned long usec)
+{
+	unsigned long long endtime;
+
+	endtime = lldiv((unsigned long long)usec * gd->arch.timer_rate_hz,
+			1000UL);
+
+	endtime += get_ticks();
+
+	while (get_ticks() < endtime)
+		;
+}
+
+ulong get_tbclk(void)
+{
+	return gd->arch.timer_rate_hz;
+}
-- 
1.7.9.5