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-rw-r--r--c/src/lib/libbsp/sparc/leon3/startup/cpucounter.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/sparc/leon3/startup/cpucounter.c b/c/src/lib/libbsp/sparc/leon3/startup/cpucounter.c
new file mode 100644
index 0000000000..2863f359e7
--- /dev/null
+++ b/c/src/lib/libbsp/sparc/leon3/startup/cpucounter.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2014 embedded brains GmbH. All rights reserved.
+ *
+ * embedded brains GmbH
+ * Dornierstr. 4
+ * 82178 Puchheim
+ * Germany
+ * <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#include <bsp.h>
+#include <leon.h>
+
+#include <rtems/counter.h>
+
+static volatile struct gptimer_regs *leon3_cpu_counter_gpt;
+
+void leon3_cpu_counter_initialize(void)
+{
+ struct ambapp_dev *adev;
+ int idx = 1;
+ volatile struct gptimer_regs *gpt;
+ unsigned new_prescaler = 8;
+ unsigned prescaler;
+ uint32_t frequency;
+
+ adev = (void *) ambapp_for_each(
+ &ambapp_plb,
+ OPTIONS_ALL | OPTIONS_APB_SLVS,
+ VENDOR_GAISLER,
+ GAISLER_GPTIMER,
+ ambapp_find_by_idx,
+ &idx
+ );
+ if (adev == NULL) {
+ rtems_fatal(RTEMS_FATAL_SOURCE_BSP_SPECIFIC, LEON3_FATAL_CPU_COUNTER_INIT);
+ }
+
+ gpt = (volatile struct gptimer_regs *) DEV_TO_APB(adev)->start;
+
+ prescaler = gpt->scaler_reload + 1;
+ gpt->scaler_reload = new_prescaler - 1;
+ gpt->timer[0].reload = 0xffffffff;
+ gpt->timer[0].ctrl = LEON3_GPTIMER_EN | LEON3_GPTIMER_RL
+ | LEON3_GPTIMER_LD;
+
+ leon3_cpu_counter_gpt = gpt;
+
+ /* Assume that GRMON initialized the timer to 1MHz */
+ frequency = UINT32_C(1000000) * (prescaler / new_prescaler);
+ rtems_counter_initialize_converter(frequency);
+}
+
+CPU_Counter_ticks _CPU_Counter_read(void)
+{
+ volatile struct gptimer_regs *gpt = leon3_cpu_counter_gpt;
+
+ return 0U - gpt->timer[0].value;
+}