From abbf5a2ef4b46218a1b24ef6afd6cf7b35a87e55 Mon Sep 17 00:00:00 2001
From: Drew Barbier <dbarbi1@gmail.com>
Date: Mon, 2 Jul 2018 00:40:06 -0500
Subject: e2 and clic start

---
 bsp/env/coreip-e2-arty/init.c | 95 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644 bsp/env/coreip-e2-arty/init.c

(limited to 'bsp/env/coreip-e2-arty/init.c')

diff --git a/bsp/env/coreip-e2-arty/init.c b/bsp/env/coreip-e2-arty/init.c
new file mode 100644
index 0000000..aaf213c
--- /dev/null
+++ b/bsp/env/coreip-e2-arty/init.c
@@ -0,0 +1,95 @@
+//See LICENSE for license details.
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "platform.h"
+#include "encoding.h"
+
+#define CPU_FREQ 32000000
+#define XSTR(x) #x
+#define STR(x) XSTR(x)
+
+extern int main(int argc, char** argv);
+
+unsigned long get_cpu_freq()
+{
+  return CPU_FREQ;
+}
+
+unsigned long get_timer_freq()
+{
+  return get_cpu_freq();
+}
+
+uint64_t get_timer_value()
+{
+#if __riscv_xlen == 32
+  while (1) {
+    uint32_t hi = read_csr(mcycleh);
+    uint32_t lo = read_csr(mcycle);
+    if (hi == read_csr(mcycleh))
+      return ((uint64_t)hi << 32) | lo;
+  }
+#else
+  return read_csr(mcycle);
+#endif
+}
+
+static void uart_init(size_t baud_rate)
+{
+  UART0_REG(UART_REG_DIV) = (get_cpu_freq() ) / baud_rate - 1;
+  UART0_REG(UART_REG_TXCTRL) |= UART_TXEN;
+}
+
+
+typedef void (*interrupt_function_ptr_t) (void);
+interrupt_function_ptr_t localISR[CLIC_NUM_INTERRUPTS] __attribute__((aligned(64)));
+
+void trap_entry(void) __attribute__((interrupt("SiFive-CLIC-preemptible"), aligned(64)));
+void trap_entry(void)
+{
+  unsigned long mcause = read_csr(mcause);
+  unsigned long mepc = read_csr(mepc);
+  if (mcause & MCAUSE_INT)  {
+    localISR[mcause & MCAUSE_CAUSE] ();
+  } else {
+    while(1);
+  }
+}
+
+#ifdef CLIC_DIRECT
+#else
+void default_handler(void)__attribute__((interrupt("SiFive-CLIC-preemptible")));;
+#endif
+void default_handler(void)
+{
+  puts("default handler\n");
+  while(1);
+}
+
+void _init()
+{
+#ifndef NO_INIT
+  uart_init(115200);
+
+  puts("core freq at " STR(CPU_FREQ) " Hz\n");
+
+//initialize vector table
+  for(int i=0;i++;i<CLIC_NUM_INTERRUPTS)  {
+    localISR[i] = &default_handler;
+  }
+  write_csr(mtvt, localISR);
+
+#ifdef CLIC_DIRECT
+  write_csr(mtvec, ((unsigned long)&trap_entry | MTVEC_CLIC));
+#else
+  write_csr(mtvec, ((unsigned long)&trap_entry | MTVEC_CLIC_VECT));
+#endif
+
+#endif
+}
+
+void _fini()
+{
+}
-- 
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