usrp2: added support for GPSDO configuration bits in EEPROM

Added instructions to install and burn eeprom to documentation.
Made gps_ctrl and gps_time sensor optional.

Added sensors for motherboard to documentation

3 files changed, 86 insertions, 5 deletions

diff --git a/host/docs/usrp2.rst b/host/docs/usrp2.rst
index 161170f2c..2eb3ee796 100644
--- a/host/docs/usrp2.rst
+++ b/host/docs/usrp2.rst
@@ -345,3 +345,51 @@ Test the PPS input with the following app:
 
     cd <install-path>/share/uhd/examples
     ./test_pps_input --args=<args>
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Internal GPSDO
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+USRP-N2XX models can have an optional internal GPSDO.
+To use the GPSDO with UHD, you must burn an EEPROM setting
+so that UHD knows that the internal GPSDO was installed.
+
+**Installation instructions:**
+
+1. Remove the daughterboard.
+2. Move J510 jumper on the motherboard from 1-2 to 2-3 in order to switch from external 10 MHz Ref Clock to GPSDO’s 10 MHz Ref Clock
+3. Screw the GPSDO module in place with the screws provided. The screws are treated to avoid loosening with vibration.
+4. Connect the GPSDO power cable to J509 on the motherboard, and then to connector D on the GPSDO module
+5. Connect an SMB to SMA cable between connectors B and J506 (PPS2)
+6. Connect an SMB to SMA cable between connectors C and J507 (CLK REF2)
+7. Connect the serial cable between connectors A and J312 (RS232-3) on the motherboard. If J312 on your USRP isn’t a keyed connector, please ensure to connect pin1 (TX) of connector A to pin3 (RX) on J312.
+8. Remove the washer and nut from the MMCX to SMA-Bulkhead cable. Connect it to connector E and then insert SMA-Bulkhead connector through the hole in the rear panel. Tighten nut to fasten in place.
+9. Replace the daughterboard pushing all the cables underneath.
+
+Then run the following commands:
+::
+
+    cd <install-path>/share/uhd/utils
+    ./usrp_burn_mb_eeprom --args=<optional device args> --key=gpsdo --val=internal
+
+**Removal instructions:**
+
+Restore the jumper setting, disconnect the cables, and unscrew the GPSDO unit.
+Then run the following commands:
+::
+
+    cd <install-path>/share/uhd/utils
+    ./usrp_burn_mb_eeprom --args=<optional device args> --key=gpsdo --val=none
+
+------------------------------------------------------------------------
+Miscellaneous
+------------------------------------------------------------------------
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Available Sensors
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+The following sensors are available for the USRP2/N-Series motherboards;
+they can be queried through the API.
+
+* mimo_locked - clock reference locked over the MIMO cable
+* ref_locked - clock reference locked (internal/external)
+* gps_time - GPS seconds (available when GPSDO installed)
diff --git a/host/lib/usrp/mboard_eeprom.cpp b/host/lib/usrp/mboard_eeprom.cpp
index c90f4a2db..869a38478 100644
--- a/host/lib/usrp/mboard_eeprom.cpp
+++ b/host/lib/usrp/mboard_eeprom.cpp
@@ -74,10 +74,17 @@ static const uhd::dict<std::string, boost::uint8_t> USRP_N100_OFFSETS = boost::a
     ("mac-addr", 0x02)
     ("ip-addr", 0x0C)
     //leave space here for other addresses (perhaps)
+    ("gpsdo", 0x17)
     ("serial", 0x18)
     ("name", 0x18 + SERIAL_LEN)
 ;
 
+enum n200_gpsdo_type{
+    N200_GPSDO_NONE = 0,
+    N200_GPSDO_INTERNAL = 1,
+    N200_GPSDO_ONBOARD = 2
+};
+
 static void load_n100(mboard_eeprom_t &mb_eeprom, i2c_iface &iface){
     //extract the revision number
     byte_vector_t rev_lsb_msb = iface.read_eeprom(N100_EEPROM_ADDR, USRP_N100_OFFSETS["rev-lsb-msb"], 2);
@@ -93,6 +100,14 @@ static void load_n100(mboard_eeprom_t &mb_eeprom, i2c_iface &iface){
     byte_copy(iface.read_eeprom(N100_EEPROM_ADDR, USRP_N100_OFFSETS["ip-addr"], 4), ip_addr_bytes);
     mb_eeprom["ip-addr"] = boost::asio::ip::address_v4(ip_addr_bytes).to_string();
 
+    //gpsdo capabilities
+    boost::uint8_t gpsdo_byte = iface.read_eeprom(N100_EEPROM_ADDR, USRP_N100_OFFSETS["gpsdo"], 1).at(0);
+    switch(n200_gpsdo_type(gpsdo_byte)){
+    case N200_GPSDO_INTERNAL: mb_eeprom["gpsdo"] = "internal"; break;
+    case N200_GPSDO_ONBOARD: mb_eeprom["gpsdo"] = "onboard"; break;
+    default: mb_eeprom["gpsdo"] = "none";
+    }
+
     //extract the serial
     mb_eeprom["serial"] = bytes_to_string(iface.read_eeprom(
         N100_EEPROM_ADDR, USRP_N100_OFFSETS["serial"], SERIAL_LEN
@@ -136,6 +151,14 @@ static void store_n100(const mboard_eeprom_t &mb_eeprom, i2c_iface &iface){
         iface.write_eeprom(N100_EEPROM_ADDR, USRP_N100_OFFSETS["ip-addr"], ip_addr_bytes);
     }
 
+    //gpsdo capabilities
+    if (mb_eeprom.has_key("gpsdo")){
+        boost::uint8_t gpsdo_byte = N200_GPSDO_NONE;
+        if (mb_eeprom["gpsdo"] == "internal") gpsdo_byte = N200_GPSDO_INTERNAL;
+        if (mb_eeprom["gpsdo"] == "onboard") gpsdo_byte = N200_GPSDO_ONBOARD;
+        iface.write_eeprom(N100_EEPROM_ADDR, USRP_N100_OFFSETS["gpsdo"], byte_vector_t(1, gpsdo_byte));
+    }
+
     //store the serial
     if (mb_eeprom.has_key("serial")) iface.write_eeprom(
         N100_EEPROM_ADDR, USRP_N100_OFFSETS["serial"],
diff --git a/host/lib/usrp/usrp2/mboard_impl.cpp b/host/lib/usrp/usrp2/mboard_impl.cpp
index 62cc3c403..ae098dba6 100644
--- a/host/lib/usrp/usrp2/mboard_impl.cpp
+++ b/host/lib/usrp/usrp2/mboard_impl.cpp
@@ -27,6 +27,7 @@
 #include <uhd/utils/byteswap.hpp>
 #include <uhd/utils/algorithm.hpp>
 #include <uhd/types/sensors.hpp>
+#include <boost/assign/list_of.hpp>
 #include <boost/bind.hpp>
 #include <iostream>
 
@@ -101,9 +102,11 @@ usrp2_mboard_impl::usrp2_mboard_impl(
     //contruct the interfaces to mboard perifs
     _clock_ctrl = usrp2_clock_ctrl::make(_iface);
     _codec_ctrl = usrp2_codec_ctrl::make(_iface);
-    _gps_ctrl = gps_ctrl::make(
-        _iface->get_gps_write_fn(),
-        _iface->get_gps_read_fn());
+    if (_iface->mb_eeprom["gpsdo"] == "internal"){
+        _gps_ctrl = gps_ctrl::make(
+            _iface->get_gps_write_fn(),
+            _iface->get_gps_read_fn());
+    }
 
     //init the dsp stuff (before setting update packets)
     dsp_init();
@@ -361,7 +364,14 @@ void usrp2_mboard_impl::get(const wax::obj &key_, wax::obj &val){
     case MBOARD_PROP_CLOCK_RATE:
         val = this->get_master_clock_freq();
         return;
-        
+
+    case SUBDEV_PROP_SENSOR_NAMES:{
+            prop_names_t names = boost::assign::list_of("mimo_locked")("ref_locked");
+            if (_gps_ctrl.get()) names.push_back("gps_time");
+            val = names;
+        }
+        return;
+
     case MBOARD_PROP_SENSOR:
         if(key.name == "mimo_locked") {
             val = sensor_value_t("MIMO", this->get_mimo_locked(), "locked", "unlocked");
@@ -371,7 +381,7 @@ void usrp2_mboard_impl::get(const wax::obj &key_, wax::obj &val){
             val = sensor_value_t("Ref", this->get_ref_locked(), "locked", "unlocked");
             return;
         }
-        else if(key.name == "gps_time") {
+        else if(key.name == "gps_time" and _gps_ctrl.get()) {
             val = sensor_value_t("GPS time", int(_gps_ctrl->get_epoch_time()), "seconds");
         }
         else {