1 files changed, 132 insertions, 0 deletions
diff --git a/bsps/riscv/riscv/console/htif.c b/bsps/riscv/riscv/console/htif.c
new file mode 100644
index 0000000000..6b9cdedc21
--- /dev/null
+++ b/bsps/riscv/riscv/console/htif.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2015 University of York.
+ * Hesham Almatary <hesham@alumni.york.ac.uk>
+ *
+ * Copyright (c) 2013, The Regents of the University of California (Regents).
+ * All Rights Reserved.
+ *
+ * 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 <dev/serial/htif.h>
+
+#include <assert.h>
+
+/* Most of the code below is copied from riscv-pk project */
+# define TOHOST_CMD(dev, cmd, payload) \
+  (((uint64_t)(dev) << 56) | ((uint64_t)(cmd) << 48) | (uint64_t)(payload))
+
+#define FROMHOST_DEV(fromhost_value) ((uint64_t)(fromhost_value) >> 56)
+#define FROMHOST_CMD(fromhost_value) ((uint64_t)(fromhost_value) << 8 >> 56)
+#define FROMHOST_DATA(fromhost_value) ((uint64_t)(fromhost_value) << 16 >> 16)
+
+volatile uint64_t tohost __attribute__((section(".htif")));
+volatile uint64_t fromhost __attribute__((section(".htif")));
+volatile uint64_t riscv_fill_up_htif_section[510] __attribute__((section(".htif")));
+volatile int htif_console_buf;
+
+static void __check_fromhost(void)
+{
+  uint64_t fh = fromhost;
+  if (!fh) {
+    return;
+  }
+  fromhost = 0;
+
+  // this should be from the console
+  assert(FROMHOST_DEV(fh) == 1);
+  switch (FROMHOST_CMD(fh)) {
+  case 0:
+    htif_console_buf = 1 + (uint8_t)FROMHOST_DATA(fh);
+    break;
+  case 1:
+    break;
+  default:
+    assert(0);
+  }
+}
+
+static void __set_tohost(uintptr_t dev, uintptr_t cmd, uintptr_t data)
+{
+  while (tohost) {
+    __check_fromhost();
+  }
+  tohost = TOHOST_CMD(dev, cmd, data);
+}
+
+int htif_console_poll_char(rtems_termios_device_context *base)
+{
+  __check_fromhost();
+  int ch = htif_console_buf;
+  if (ch >= 0) {
+    htif_console_buf = -1;
+    __set_tohost(1, 0, 0);
+  }
+
+  return ch - 1;
+}
+
+void htif_console_write_polled(
+  rtems_termios_device_context *base,
+  const char *buf,
+  size_t len
+)
+{
+  size_t i;
+
+  for (i = 0; i < len; ++i) {
+    __set_tohost(1, 1, buf[i]);
+  }
+}
+
+void htif_poweroff(void)
+{
+  while (1) {
+    fromhost = 0;
+    tohost = 1;
+  }
+}
+
+void htif_console_context_init(
+  rtems_termios_device_context *base,
+  int device_tree_node
+)
+{
+  rtems_termios_device_context_initialize(base, "HTIF");
+}
+
+static bool htif_console_first_open(
+  struct rtems_termios_tty *tty,
+  rtems_termios_device_context *base,
+  struct termios *term,
+  rtems_libio_open_close_args_t *args
+)
+{
+  return true;
+}
+
+const rtems_termios_device_handler htif_console_handler = {
+  .first_open = htif_console_first_open,
+  .write = htif_console_write_polled,
+  .poll_read = htif_console_poll_char,
+  .mode = TERMIOS_POLLED
+};