Native VPP driver for Intel Niantic family of NICs

Available only in vpp_lite platform

Change-Id: I09d112af5f7f4521ec25196ecdd8c02c20eedd5f
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/vlib/Makefile.am b/vlib/Makefile.am
index 981c2be..2747567 100644
--- a/vlib/Makefile.am
+++ b/vlib/Makefile.am
@@ -31,6 +31,7 @@
   vlib/counter.c				\
   vlib/error.c					\
   vlib/format.c					\
+  vlib/i2c.c					\
   vlib/init.c					\
   vlib/main.c					\
   vlib/mc.c					\
@@ -61,6 +62,7 @@
   vlib/error.h					\
   vlib/format_funcs.h				\
   vlib/global_funcs.h				\
+  vlib/i2c.h					\
   vlib/init.h					\
   vlib/main.h					\
   vlib/mc.h					\
diff --git a/vlib/vlib/i2c.c b/vlib/vlib/i2c.c
new file mode 100644
index 0000000..83a702e
--- /dev/null
+++ b/vlib/vlib/i2c.c
@@ -0,0 +1,222 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/i2c.h>
+
+static inline void
+i2c_delay (i2c_bus_t * b, f64 timeout)
+{
+  vlib_main_t * vm = vlib_get_main();
+  vlib_time_wait (vm, timeout);
+}
+
+static void
+i2c_wait_for_scl (i2c_bus_t * b)
+{
+  f64 t = 0;
+
+  while (t < b->hold_time)
+    {
+      int sda, scl;
+      i2c_delay(b, b->rise_fall_time);
+      b->get_bits (b, &scl, &sda);
+
+      if (scl)
+	return;
+
+      t += b->rise_fall_time;
+    }
+  b->timeout = 1;
+}
+
+static void
+i2c_start (i2c_bus_t * b)
+{
+  b->timeout = 0;
+
+  b->put_bits (b, 1, 1);
+  i2c_wait_for_scl (b);
+
+  if (vlib_i2c_bus_timed_out (b))
+    return;
+
+  b->put_bits (b, 1, 0);
+  i2c_delay (b, b->hold_time);
+  b->put_bits (b, 0, 0);
+  i2c_delay (b, b->hold_time);
+}
+
+static void
+i2c_stop (i2c_bus_t * b)
+{
+  b->put_bits (b, 0, 0);
+  i2c_delay (b, b->rise_fall_time);
+
+  b->put_bits (b, 1, 0);
+  i2c_delay (b, b->hold_time);
+
+  b->put_bits (b, 1, 1);
+  i2c_delay (b, b->hold_time);
+}
+
+static void
+i2c_write_bit (i2c_bus_t * b, int sda)
+{
+  b->put_bits (b, 0, sda);
+  i2c_delay (b, b->rise_fall_time);
+
+  b->put_bits (b, 1, sda);
+  i2c_wait_for_scl (b);
+  i2c_delay (b, b->hold_time);
+
+  b->put_bits (b, 0, sda);
+  i2c_delay (b, b->rise_fall_time);
+}
+
+static void
+i2c_read_bit (i2c_bus_t * b, int * sda)
+{
+  int scl;
+
+  b->put_bits (b, 1, 1);
+  i2c_wait_for_scl (b);
+  i2c_delay (b, b->hold_time);
+
+  b->get_bits (b, &scl, sda);
+
+  b->put_bits (b, 0, 1);
+  i2c_delay (b, b->rise_fall_time);
+}
+
+static void
+i2c_write_byte (i2c_bus_t * b, u8 data)
+{
+  int i, sda;
+
+  for (i = 7; i >= 0; i--)
+    {
+      i2c_write_bit (b, (data >> i) & 1);
+      if (b->timeout)
+	return;
+    }
+
+  b->put_bits (b, 0, 1);
+  i2c_delay (b, b->rise_fall_time);
+
+  i2c_read_bit(b, &sda);
+
+  if (sda)
+    b->timeout = 1;
+}
+
+
+static void
+i2c_read_byte (i2c_bus_t * b, u8 * data, int ack)
+{
+  int i, sda;
+
+  *data = 0;
+
+  b->put_bits (b, 0, 1);
+  i2c_delay (b, b->rise_fall_time);
+
+  for (i = 7; i >= 0; i--)
+    {
+      i2c_read_bit (b, &sda);
+      if (b->timeout)
+	return;
+
+      *data |= (sda != 0) << i;
+    }
+
+  i2c_write_bit (b, ack == 0);
+}
+
+
+void
+vlib_i2c_init (i2c_bus_t * b)
+{
+  f64 tick;
+  if (!b->clock)
+    b->clock = 400000;
+
+  tick = 1.0 / b->clock;
+
+  /* Spend 40% of time in low and high states */
+  if (!b->hold_time)
+    b->hold_time = 0.4 * tick;
+
+  /* Spend 10% of time waiting for rise and fall */
+  if (!b->rise_fall_time)
+    b->rise_fall_time = 0.1 * tick;
+}
+
+void
+vlib_i2c_xfer (i2c_bus_t * bus, i2c_msg_t * msgs)
+{
+  i2c_msg_t *msg;
+  int i;
+
+  vec_foreach (msg, msgs)
+    {
+      i2c_start (bus);
+      i2c_write_byte (bus, (msg->addr << 1) + (msg->flags == I2C_MSG_FLAG_READ));
+
+      if (msg->flags & I2C_MSG_FLAG_READ)
+	for (i=0; i< msg->len; i++)
+	  {
+	    i2c_read_byte (bus, &msg->buffer[i], /* ack */ i + 1 != msg->len);
+	    if (bus->timeout)
+	      goto done;
+	  }
+
+      else
+	for (i=0; i< msg->len; i++)
+	  {
+	    i2c_write_byte (bus, msg->buffer[i]);
+	    if (bus->timeout)
+	      goto done;
+	  }
+    }
+
+done:
+  i2c_stop(bus);
+}
+
+void
+vlib_i2c_read_eeprom (i2c_bus_t * bus, u8 i2c_addr, u16 start_addr, u16 length, u8 * data)
+{
+  i2c_msg_t * msg = 0;
+  u8 start_address[1];
+
+  vec_validate (msg, 1);
+
+  start_address[0] = start_addr;
+  msg[0].addr = i2c_addr;
+  msg[0].flags = I2C_MSG_FLAG_WRITE;
+  msg[0].buffer = (u8 *) &start_address;
+  msg[0].len = 1;
+
+  msg[1].addr = i2c_addr;
+  msg[1].flags = I2C_MSG_FLAG_READ;
+  msg[1].buffer = data;
+  msg[1].len = length;
+
+  vlib_i2c_xfer(bus, msg);
+
+  vec_free (msg);
+}
+
diff --git a/vlib/vlib/i2c.h b/vlib/vlib/i2c.h
new file mode 100644
index 0000000..451957d
--- /dev/null
+++ b/vlib/vlib/i2c.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef included_vlib_i2c_h
+#define included_vlib_i2c_h
+
+#include <vppinfra/types.h>
+
+
+#define I2C_MSG_FLAG_WRITE  0
+#define I2C_MSG_FLAG_READ   1
+
+typedef struct {
+    u8 addr;
+    u8 flags;
+    u16 len;
+    u8 * buffer;
+} i2c_msg_t;
+
+typedef struct i2c_bus_t {
+  void (* put_bits) (struct i2c_bus_t * b, int  scl, int  sda);
+  void (* get_bits) (struct i2c_bus_t * b, int *scl, int *sda);
+
+  int timeout;
+  u32 clock;
+  f64 hold_time;
+  f64 rise_fall_time;
+
+  /* Private data */
+  uword private_data;
+
+} i2c_bus_t;
+
+void vlib_i2c_init (i2c_bus_t * bus);
+void vlib_i2c_xfer (i2c_bus_t * bus, i2c_msg_t * msgs);
+void vlib_i2c_read_eeprom (i2c_bus_t * bus, u8 i2c_addr, u16 start_addr, u16 length, u8 * data);
+
+static inline int
+vlib_i2c_bus_timed_out(i2c_bus_t * bus)
+{
+  return bus->timeout;
+}
+
+#endif /* included_vlib_i2c_h */
+
diff --git a/vlib/vlib/physmem.h b/vlib/vlib/physmem.h
index 6e70291..6f75a0f 100644
--- a/vlib/vlib/physmem.h
+++ b/vlib/vlib/physmem.h
@@ -53,6 +53,9 @@
   uword page_mask;
 
   u64 * page_table;
+
+  /* is fake physmem */
+  u8 is_fake;
 } vlib_physmem_main_t;
 
 always_inline u64
diff --git a/vlib/vlib/unix/physmem.c b/vlib/vlib/unix/physmem.c
index 67c2233..d3155e0 100644
--- a/vlib/vlib/unix/physmem.c
+++ b/vlib/vlib/unix/physmem.c
@@ -245,6 +245,7 @@
   vpm->virtual.start = pointer_to_uword (pm->mem);
   vpm->virtual.size = pm->mem_size;
   vpm->virtual.end = vpm->virtual.start + vpm->virtual.size;
+  vpm->is_fake = 1;
 
   fformat(stderr, "%s: use fake dma pages\n", __FUNCTION__);
 
diff --git a/vlib/vlib/unix/unix.h b/vlib/vlib/unix/unix.h
index 75d5df0..6c1f985 100644
--- a/vlib/vlib/unix/unix.h
+++ b/vlib/vlib/unix/unix.h
@@ -180,6 +180,13 @@
 clib_error_t * unix_physmem_init (vlib_main_t * vm,
 				  int fail_if_physical_memory_not_present);
 
+static inline int
+unix_physmem_is_fake (vlib_main_t * vm)
+{
+  vlib_physmem_main_t * vpm = &vm->physmem_main;
+  return vpm->is_fake;
+}
+
 /* Set prompt for CLI. */
 void vlib_unix_cli_set_prompt (char * prompt);