1 files changed, 159 insertions, 0 deletions
diff --git a/bsps/microblaze/microblaze_fpga/clock/clock.c b/bsps/microblaze/microblaze_fpga/clock/clock.c
new file mode 100644
index 0000000000..16acbaeebb
--- /dev/null
+++ b/bsps/microblaze/microblaze_fpga/clock/clock.c
@@ -0,0 +1,159 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSBSPsMicroblaze
+ *
+ * @brief MicroBlaze AXI Timer clock support
+ */
+
+/*
+ * Copyright (C) 2021 On-Line Applications Research Corporation (OAR)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <bsp.h>
+#include <bsp/fatal.h>
+#include <bsp/timer.h>
+
+#include <rtems.h>
+#include <rtems/irq-extension.h>
+#include <rtems/timecounter.h>
+
+static rtems_timecounter_simple mblaze_tc;
+static volatile Microblaze_Timer *mblaze_timer;
+
+static uint32_t microblaze_tc_get( rtems_timecounter_simple *tc )
+{
+  return mblaze_timer->tcr0;
+}
+
+static bool microblaze_tc_is_pending( rtems_timecounter_simple *tc )
+{
+  return ( mblaze_timer->tcsr0 & MICROBLAZE_TIMER_TCSR0_T0INT ) != 0;
+}
+
+static uint32_t microblaze_tc_get_timecount( struct timecounter *tc )
+{
+  return rtems_timecounter_simple_downcounter_get(
+    tc,
+    microblaze_tc_get,
+    microblaze_tc_is_pending
+  );
+}
+
+static void microblaze_clock_initialize( void )
+{
+  mblaze_timer = (volatile Microblaze_Timer *) try_get_prop_from_device_tree(
+    "xlnx,xps-timer-1.00.a",
+    "reg",
+    BSP_MICROBLAZE_FPGA_TIMER_BASE
+  );
+
+  /* Set load register to 0 */
+  mblaze_timer->tlr0 = 0;
+  /* Reset the timer and interrupt */
+  mblaze_timer->tcsr0 = MICROBLAZE_TIMER_TCSR0_T0INT | MICROBLAZE_TIMER_TCSR0_LOAD0;
+  /* Release the reset */
+  mblaze_timer->tcsr0 = 0;
+  /*
+   * Enable interrupt, auto reload mode, external interrupt signal,
+   * and down counter
+   */
+  mblaze_timer->tcsr0 =  MICROBLAZE_TIMER_TCSR0_ARHT0 | MICROBLAZE_TIMER_TCSR0_ENIT0 |
+                  MICROBLAZE_TIMER_TCSR0_GENT0 | MICROBLAZE_TIMER_TCSR0_UDT0;
+
+  uint64_t us_per_tick = rtems_configuration_get_microseconds_per_tick();
+  uint32_t counter_frequency_in_hz = try_get_prop_from_device_tree(
+    "xlnx,xps-timer-1.00.a",
+    "clock-frequency",
+    BSP_MICROBLAZE_FPGA_TIMER_FREQUENCY
+  );
+  uint32_t counter_ticks_per_clock_tick =
+    ( counter_frequency_in_hz * us_per_tick ) / 1000000;
+
+  /* Set a reset value for the timer counter */
+  mblaze_timer->tlr0 = counter_ticks_per_clock_tick;
+  uint32_t control_status_reg = mblaze_timer->tcsr0;
+  /* Load the reset value into the counter register */
+  mblaze_timer->tcsr0 = MICROBLAZE_TIMER_TCSR0_LOAD0;
+  /* Enable the timer */
+  mblaze_timer->tcsr0 = control_status_reg | MICROBLAZE_TIMER_TCSR0_ENT0;
+
+  rtems_timecounter_simple_install(
+    &mblaze_tc,
+    counter_frequency_in_hz,
+    counter_ticks_per_clock_tick,
+    microblaze_tc_get_timecount
+  );
+}
+
+static void microblaze_clock_at_tick( rtems_timecounter_simple *tc )
+{
+  if ( ( mblaze_timer->tcsr0 & MICROBLAZE_TIMER_TCSR0_T0INT ) == 0 ) {
+    return;
+  }
+  /* Clear the interrupt */
+  mblaze_timer->tcsr0 |= MICROBLAZE_TIMER_TCSR0_T0INT;
+}
+
+static void microblaze_tc_tick( rtems_timecounter_simple *tc )
+{
+  rtems_timecounter_simple_downcounter_tick(
+    tc,
+    microblaze_tc_get,
+    microblaze_clock_at_tick
+  );
+}
+
+static void microblaze_clock_handler_install( rtems_interrupt_handler isr )
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+
+  uint32_t clock_irq_num = try_get_prop_from_device_tree(
+    "xlnx,xps-timer-1.00.a",
+    "interrupts",
+    0
+  );
+
+  sc = rtems_interrupt_handler_install(
+    clock_irq_num,
+    "Clock",
+    RTEMS_INTERRUPT_UNIQUE,
+    isr,
+    &mblaze_tc
+  );
+
+  if ( sc != RTEMS_SUCCESSFUL ) {
+    bsp_fatal( MICROBLAZE_FATAL_CLOCK_IRQ_INSTALL );
+  }
+}
+
+#define Clock_driver_support_initialize_hardware() microblaze_clock_initialize()
+#define Clock_driver_support_install_isr( isr ) \
+  microblaze_clock_handler_install( isr )
+#define Clock_driver_timecounter_tick(arg) microblaze_tc_tick(arg)
+
+/* Include shared source clock driver code */
+#include "../../shared/dev/clock/clockimpl.h"