[U-Boot] [Patch 8/16] add mips64/time.c

Zhi-zhou Zhang etou.zh at gmail.com
Tue Aug 14 17:09:02 CEST 2012


diff --git a/arch/mips/cpu/mips64/time.c b/arch/mips/cpu/mips64/time.c
new file mode 100644
index 0000000..350896a
--- /dev/null
+++ b/arch/mips/cpu/mips64/time.c
@@ -0,0 +1,86 @@
+/*
+ * (C) Copyright 2003
+ * Wolfgang Denk, DENX Software Engineering, wd 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 <common.h>
+#include <asm/mipsregs.h>
+
+static unsigned long timestamp;
+
+/* how many counter cycles in a jiffy */
+#define CYCLES_PER_JIFFY (CONFIG_SYS_MIPS_TIMER_FREQ + CONFIG_SYS_HZ / 2)
/ CONFIG_SYS_HZ
+
+/*
+ * timer without interrupts
+ */
+
+int timer_init(void)
+{
+ /* Set up the timer for the first expiration. */
+ timestamp = 0;
+ write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
+
+ return 0;
+}
+
+ulong get_timer(ulong base)
+{
+ unsigned int count;
+ unsigned int expirelo = read_c0_compare();
+
+ /* Check to see if we have missed any timestamps. */
+ count = read_c0_count();
+ while ((count - expirelo) < 0x7fffffff) {
+ expirelo += CYCLES_PER_JIFFY;
+ timestamp++;
+ }
+ write_c0_compare(expirelo);
+
+ return (timestamp - base);
+}
+
+void __udelay(unsigned long usec)
+{
+ unsigned int tmo;
+
+ tmo = read_c0_count() + (usec * (CONFIG_SYS_MIPS_TIMER_FREQ / 1000000));
+ while ((tmo - read_c0_count()) < 0x7fffffff)
+ /*NOP*/;
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On MIPS 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 MIPS it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return CONFIG_SYS_HZ;
+}

-- 
Regards,
Zhizhou Zhang


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