[PATCH 08/15] HiFive1: add irq dispatching function

[Denis Obrezkov]

---
 c/src/lib/libbsp/riscv32/hifive1/irq/irq.c | 90 ++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 c/src/lib/libbsp/riscv32/hifive1/irq/irq.c

diff --git a/c/src/lib/libbsp/riscv32/hifive1/irq/irq.c b/c/src/lib/libbsp/riscv32/hifive1/irq/irq.c
new file mode 100644
index 0000000..6fd4e75
--- /dev/null
+++ b/c/src/lib/libbsp/riscv32/hifive1/irq/irq.c
@@ -0,0 +1,90 @@
+/**
+ * @file
+ *
+ * @ingroup riscv_interrupt
+ *
+ * @brief Interrupt support.
+ */
+
+/*
+ * RISCV CPU Dependent Source
+ *
+ * Copyright (c) 2015 University of York.
+ * Hesham ALMatary <hmka501 at york.ac.uk>
+ *
+ * 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 AUTHOR 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 AUTHOR 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/fe310.h>
+#include <bsp/irq.h>
+#include <bsp/irq-generic.h>
+
+/* Almost all of the jobs that the following functions should
+ * do are implemented in cpukit
+ */
+
+void bsp_interrupt_handler_default(rtems_vector_number vector)
+{
+    printk("spurious interrupt: %u\n", vector);
+}
+
+rtems_status_code bsp_interrupt_facility_initialize()
+{
+  return 0;
+}
+
+rtems_status_code bsp_interrupt_vector_enable(rtems_vector_number vector)
+{
+  return 0;
+}
+
+rtems_status_code bsp_interrupt_vector_disable(rtems_vector_number vector)
+{
+  return 0;
+}
+
+static uint32_t cause = 0;
+volatile uint64_t * mtimecmp = (volatile uint64_t *)0x02004000;
+volatile uint64_t * mtime = (volatile uint64_t *)0x0200bff8;
+
+void handle_trap_new ()
+{
+    asm volatile ("csrr %0, mcause": "=r" (cause));
+    if (cause & MCAUSE_INT) { 
+      /* an interrupt occurred */
+      if ((cause & MCAUSE_MTIME) == MCAUSE_MTIME) {
+	/* Timer interrupt */
+	    (*mtimecmp) = (*mtime) + FE310_CLOCK_PERIOD;
+        bsp_interrupt_handler_table[1].handler(bsp_interrupt_handler_table[1].arg);
+      } else if ((cause & MCAUSE_MEXT) == MCAUSE_MEXT) {
+	      /*External interrupt */
+          asm volatile ("csrci mie, 0x800");
+      } else if ((cause & MCAUSE_MSWI) == MCAUSE_MSWI) {
+	      /* Software interrupt */
+	      volatile uint32_t * msip_reg = (volatile uint32_t *) 0x02000000;
+	      *msip_reg = 0;
+      }
+    } else {
+      /* an exception occurred */
+    }
+
+}
-- 
2.1.4