[rtems commit] bsps/arm: Add ARMv7-AR Generic Timer clock driver

Sebastian Huber sebh at rtems.org
Fri Aug 4 12:25:43 UTC 2017


Module:    rtems
Branch:    master
Commit:    ffe7c0e74971fa7ad16f948f23b19688e18725c2
Changeset: http://git.rtems.org/rtems/commit/?id=ffe7c0e74971fa7ad16f948f23b19688e18725c2

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Fri Aug  4 13:56:42 2017 +0200

bsps/arm: Add ARMv7-AR Generic Timer clock driver

Update #3090.

---

 .../arm/shared/arm-generic-timer-clock-config.c    | 205 +++++++++++++++++++++
 c/src/lib/libbsp/shared/include/fatal.h            |   1 +
 2 files changed, 206 insertions(+)

diff --git a/c/src/lib/libbsp/arm/shared/arm-generic-timer-clock-config.c b/c/src/lib/libbsp/arm/shared/arm-generic-timer-clock-config.c
new file mode 100644
index 0000000..67e0d59
--- /dev/null
+++ b/c/src/lib/libbsp/arm/shared/arm-generic-timer-clock-config.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 2017 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <info at 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.org/license/LICENSE.
+ */
+
+#include <bsp.h>
+#include <bsp/fatal.h>
+#include <bsp/irq.h>
+#include <bsp/irq-generic.h>
+
+#include <rtems/counter.h>
+#include <rtems/sysinit.h>
+#include <rtems/timecounter.h>
+#include <rtems/score/smpimpl.h>
+
+#include <libcpu/arm-cp15.h>
+
+/*
+ * Clock driver using the ARMv7-AR Generic Timer.  The BSP must provide the
+ * following function via <bsp.h>:
+ *
+ * void arm_generic_timer_get_config(uint32_t *frequency, uint32_t *irq);
+ *
+ * The BSP may optionally define ARM_GENERIC_TIMER_USE_VIRTUAL in <bsp.h> to
+ * use the virtual timer instead of the physical timer.
+ */
+
+typedef struct {
+  struct timecounter tc;
+  uint32_t interval;
+  rtems_vector_number irq;
+} arm_gt_clock_context;
+
+static arm_gt_clock_context arm_gt_clock_instance;
+
+/* This is defined in clockdrv_shell.h */
+void Clock_isr(rtems_irq_hdl_param arg);
+
+static inline uint64_t arm_gt_clock_get_compare_value(void)
+{
+#ifdef ARM_GENERIC_TIMER_USE_VIRTUAL
+  return arm_cp15_get_counter_pl1_virtual_compare_value();
+#else
+  return arm_cp15_get_counter_pl1_physical_compare_value();
+#endif
+}
+
+static inline void arm_gt_clock_set_compare_value(uint64_t cval)
+{
+#ifdef ARM_GENERIC_TIMER_USE_VIRTUAL
+  arm_cp15_set_counter_pl1_virtual_compare_value(cval);
+#else
+  arm_cp15_set_counter_pl1_physical_compare_value(cval);
+#endif
+}
+
+static inline uint64_t arm_gt_clock_get_count(void)
+{
+#ifdef ARM_GENERIC_TIMER_USE_VIRTUAL
+  return arm_cp15_get_counter_virtual_count();
+#else
+  return arm_cp15_get_counter_physical_count();
+#endif
+}
+
+static inline void arm_gt_clock_set_control(uint32_t ctl)
+{
+#ifdef ARM_GENERIC_TIMER_USE_VIRTUAL
+  arm_cp15_set_counter_pl1_virtual_timer_control(ctl);
+#else
+  arm_cp15_set_counter_pl1_physical_timer_control(ctl);
+#endif
+}
+
+static void arm_gt_clock_at_tick(void)
+{
+  uint64_t cval;
+  uint32_t interval;
+
+  interval = arm_gt_clock_instance.interval;
+  cval = arm_gt_clock_get_compare_value();
+  cval += interval;
+  arm_gt_clock_set_compare_value(cval);
+}
+
+static void arm_gt_clock_handler_install(void)
+{
+  rtems_status_code sc;
+
+  sc = rtems_interrupt_handler_install(
+    arm_gt_clock_instance.irq,
+    "Clock",
+    RTEMS_INTERRUPT_UNIQUE,
+    (rtems_interrupt_handler) Clock_isr,
+    NULL
+  );
+  if (sc != RTEMS_SUCCESSFUL) {
+    bsp_fatal(BSP_ARM_FATAL_GENERIC_TIMER_CLOCK_IRQ_INSTALL);
+  }
+}
+
+static uint32_t arm_gt_clock_get_timecount(struct timecounter *tc)
+{
+  return (uint32_t) arm_gt_clock_get_count();
+}
+
+static void arm_gt_clock_gt_init(uint64_t cval)
+{
+  arm_gt_clock_set_compare_value(cval);
+  arm_gt_clock_set_control(0x1);
+}
+
+#if defined(RTEMS_SMP) && !defined(CLOCK_DRIVER_USE_ONLY_BOOT_PROCESSOR)
+static void arm_gt_clock_secondary_action(void *arg)
+{
+  uint64_t *cval;
+
+  cval = arg;
+  arm_gt_clock_gt_init(*cval);
+  bsp_interrupt_vector_enable(arm_gt_clock_instance.irq);
+}
+#endif
+
+static void arm_gt_clock_secondary_initialization(uint64_t cval)
+{
+#if defined(RTEMS_SMP) && !defined(CLOCK_DRIVER_USE_ONLY_BOOT_PROCESSOR)
+  _SMP_Before_multitasking_action_broadcast(
+    arm_gt_clock_secondary_action,
+    &cval
+  );
+#endif
+}
+
+static void arm_gt_clock_initialize(void)
+{
+  uint64_t frequency;
+  uint64_t us_per_tick;
+  uint32_t interval;
+  uint64_t cval;
+  struct timecounter *tc;
+
+  frequency = arm_gt_clock_instance.interval;
+  us_per_tick = rtems_configuration_get_microseconds_per_tick();
+  interval = (uint32_t) ((frequency * us_per_tick) / 1000000);
+  cval = arm_gt_clock_get_count();
+  cval += interval;
+  arm_gt_clock_instance.interval = interval;
+
+  arm_gt_clock_gt_init(cval);
+  arm_gt_clock_secondary_initialization(cval);
+
+  tc = &arm_gt_clock_instance.tc;
+  tc->tc_get_timecount = arm_gt_clock_get_timecount;
+  tc->tc_counter_mask = 0xffffffff;
+  tc->tc_frequency = frequency;
+  tc->tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER;
+  rtems_timecounter_install(tc);
+}
+
+CPU_Counter_ticks _CPU_Counter_read(void)
+{
+  return (uint32_t) arm_gt_clock_get_count();
+}
+
+static void arm_gt_clock_early_init(void)
+{
+  arm_gt_clock_set_control(0x3);
+
+  arm_generic_timer_get_config(
+    &arm_gt_clock_instance.interval,
+    &arm_gt_clock_instance.irq
+  );
+
+  rtems_counter_initialize_converter(arm_gt_clock_instance.interval);
+}
+
+RTEMS_SYSINIT_ITEM(
+  arm_gt_clock_early_init,
+  RTEMS_SYSINIT_BSP_START,
+  RTEMS_SYSINIT_ORDER_LAST
+);
+
+#define Clock_driver_support_at_tick() \
+  arm_gt_clock_at_tick()
+
+#define Clock_driver_support_initialize_hardware() \
+  arm_gt_clock_initialize()
+
+#define Clock_driver_support_install_isr(isr, old_isr) \
+  do { \
+    arm_gt_clock_handler_install(); \
+    old_isr = NULL; \
+  } while (0)
+
+/* Include shared source clock driver code */
+#include "../../shared/clockdrv_shell.h"
diff --git a/c/src/lib/libbsp/shared/include/fatal.h b/c/src/lib/libbsp/shared/include/fatal.h
index fd8b678..1bdfde6 100644
--- a/c/src/lib/libbsp/shared/include/fatal.h
+++ b/c/src/lib/libbsp/shared/include/fatal.h
@@ -50,6 +50,7 @@ typedef enum {
   BSP_ARM_PL111_FATAL_SEM_RELEASE,
   BSP_ARM_A9MPCORE_FATAL_CLOCK_SMP_INIT,
   BSP_ARM_ARMV7M_CPU_COUNTER_INIT,
+  BSP_ARM_FATAL_GENERIC_TIMER_CLOCK_IRQ_INSTALL,
 
   /* LEON3 fatal codes */
   LEON3_FATAL_NO_IRQMP_CONTROLLER = BSP_FATAL_CODE_BLOCK(2),




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