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-rw-r--r--arch/mips/cavium-octeon/csrc-octeon.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/csrc-octeon.c b/arch/mips/cavium-octeon/csrc-octeon.c
new file mode 100644
index 00000000000..70fd92c3165
--- /dev/null
+++ b/arch/mips/cavium-octeon/csrc-octeon.c
@@ -0,0 +1,58 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2007 by Ralf Baechle
+ */
+#include <linux/clocksource.h>
+#include <linux/init.h>
+
+#include <asm/time.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-ipd-defs.h>
+
+/*
+ * Set the current core's cvmcount counter to the value of the
+ * IPD_CLK_COUNT. We do this on all cores as they are brought
+ * on-line. This allows for a read from a local cpu register to
+ * access a synchronized counter.
+ *
+ */
+void octeon_init_cvmcount(void)
+{
+ unsigned long flags;
+ unsigned loops = 2;
+
+ /* Clobber loops so GCC will not unroll the following while loop. */
+ asm("" : "+r" (loops));
+
+ local_irq_save(flags);
+ /*
+ * Loop several times so we are executing from the cache,
+ * which should give more deterministic timing.
+ */
+ while (loops--)
+ write_c0_cvmcount(cvmx_read_csr(CVMX_IPD_CLK_COUNT));
+ local_irq_restore(flags);
+}
+
+static cycle_t octeon_cvmcount_read(void)
+{
+ return read_c0_cvmcount();
+}
+
+static struct clocksource clocksource_mips = {
+ .name = "OCTEON_CVMCOUNT",
+ .read = octeon_cvmcount_read,
+ .mask = CLOCKSOURCE_MASK(64),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+void __init plat_time_init(void)
+{
+ clocksource_mips.rating = 300;
+ clocksource_set_clock(&clocksource_mips, mips_hpt_frequency);
+ clocksource_register(&clocksource_mips);
+}