usrp3: Added support for pre-FIFO TX flowcontrol

- tx_vita_core_3000 can now monitor for flow-control immediately
  before the radio or immediately before the radio external FIFO
- B200 does not have an external FIFO so it will use the default config

2 files changed, 51 insertions, 22 deletions

diff --git a/host/lib/usrp/cores/tx_vita_core_3000.cpp b/host/lib/usrp/cores/tx_vita_core_3000.cpp
index 71a2b7e21..c76b384d9 100644
--- a/host/lib/usrp/cores/tx_vita_core_3000.cpp
+++ b/host/lib/usrp/cores/tx_vita_core_3000.cpp
@@ -18,9 +18,11 @@
 #include "tx_vita_core_3000.hpp"
 #include <uhd/utils/safe_call.hpp>
 
-#define REG_CTRL_ERROR_POLICY           _base + 0
-#define REG_DEFRAMER_CYCLE_FC_UPS       _base + 2*4 + 0
-#define REG_DEFRAMER_PACKET_FC_UPS      _base + 2*4 + 4
+#define REG_CTRL_ERROR_POLICY       (_base + 0)
+#define REG_FC_PRE_RADIO_RESP_BASE  (_base + 2*4)
+#define REG_FC_PRE_FIFO_RESP_BASE   (_base + 4*4)
+#define REG_CTRL_FC_CYCLE_OFFSET    (0*4)
+#define REG_CTRL_FC_PACKET_OFFSET   (1*4)
 
 using namespace uhd;
 
@@ -32,12 +34,22 @@ struct tx_vita_core_3000_impl : tx_vita_core_3000
 {
     tx_vita_core_3000_impl(
         wb_iface::sptr iface,
-        const size_t base
+        const size_t base,
+        fc_monitor_loc fc_location
     ):
         _iface(iface),
-        _base(base)
+        _base(base),
+        _fc_base((fc_location==FC_PRE_RADIO or fc_location==FC_DEFAULT) ?
+                    REG_FC_PRE_RADIO_RESP_BASE : REG_FC_PRE_FIFO_RESP_BASE),
+        _fc_location(fc_location)
     {
-        this->set_tick_rate(1); //init to non zero
+        if (fc_location != FC_DEFAULT) {
+            //Turn off the other FC monitoring module
+            const size_t other_fc_base = (fc_location==FC_PRE_RADIO) ?
+                    REG_FC_PRE_FIFO_RESP_BASE : REG_FC_PRE_RADIO_RESP_BASE;
+            _iface->poke32(other_fc_base + REG_CTRL_FC_CYCLE_OFFSET, 0);
+            _iface->poke32(other_fc_base + REG_CTRL_FC_PACKET_OFFSET, 0);
+        }
         this->set_underflow_policy("next_packet");
         this->clear();
     }
@@ -56,11 +68,6 @@ struct tx_vita_core_3000_impl : tx_vita_core_3000
         this->set_underflow_policy(_policy); //clears the seq
     }
 
-    void set_tick_rate(const double rate)
-    {
-        _tick_rate = rate;
-    }
-
     void set_underflow_policy(const std::string &policy)
     {
         if (policy == "next_packet")
@@ -89,23 +96,35 @@ struct tx_vita_core_3000_impl : tx_vita_core_3000
 
     void configure_flow_control(const size_t cycs_per_up, const size_t pkts_per_up)
     {
-        if (cycs_per_up == 0) _iface->poke32(REG_DEFRAMER_CYCLE_FC_UPS, 0);
-        else _iface->poke32(REG_DEFRAMER_CYCLE_FC_UPS, (1 << 31) | ((cycs_per_up) & 0xffffff));
+        if (cycs_per_up == 0) _iface->poke32(_fc_base + REG_CTRL_FC_CYCLE_OFFSET, 0);
+        else _iface->poke32(_fc_base + REG_CTRL_FC_CYCLE_OFFSET, (1 << 31) | ((cycs_per_up) & 0xffffff));
 
-        if (pkts_per_up == 0) _iface->poke32(REG_DEFRAMER_PACKET_FC_UPS, 0);
-        else _iface->poke32(REG_DEFRAMER_PACKET_FC_UPS, (1 << 31) | ((pkts_per_up) & 0xffff));
+        if (pkts_per_up == 0) _iface->poke32(_fc_base + REG_CTRL_FC_PACKET_OFFSET, 0);
+        else _iface->poke32(_fc_base + REG_CTRL_FC_PACKET_OFFSET, (1 << 31) | ((pkts_per_up) & 0xffff));
     }
 
-    wb_iface::sptr _iface;
-    const size_t _base;
-    double _tick_rate;
-    std::string _policy;
+    wb_iface::sptr  _iface;
+    const size_t    _base;
+    const size_t    _fc_base;
+    std::string     _policy;
+    fc_monitor_loc  _fc_location;
+
 };
 
 tx_vita_core_3000::sptr tx_vita_core_3000::make(
     wb_iface::sptr iface,
+    const size_t base,
+    fc_monitor_loc fc_location
+)
+{
+    return tx_vita_core_3000::sptr(new tx_vita_core_3000_impl(iface, base, fc_location));
+}
+
+tx_vita_core_3000::sptr tx_vita_core_3000::make_no_radio_buff(
+    wb_iface::sptr iface,
     const size_t base
 )
 {
-    return tx_vita_core_3000::sptr(new tx_vita_core_3000_impl(iface, base));
+    //No internal radio buffer so only pre-radio monitoring is supported.
+    return tx_vita_core_3000::sptr(new tx_vita_core_3000_impl(iface, base, FC_DEFAULT));
 }
diff --git a/host/lib/usrp/cores/tx_vita_core_3000.hpp b/host/lib/usrp/cores/tx_vita_core_3000.hpp
index 4c0052d4f..bd0f20ba4 100644
--- a/host/lib/usrp/cores/tx_vita_core_3000.hpp
+++ b/host/lib/usrp/cores/tx_vita_core_3000.hpp
@@ -32,17 +32,27 @@ class tx_vita_core_3000 : boost::noncopyable
 public:
     typedef boost::shared_ptr<tx_vita_core_3000> sptr;
 
+    enum fc_monitor_loc {
+        FC_DEFAULT,
+        FC_PRE_RADIO,
+        FC_PRE_FIFO
+    };
+
     virtual ~tx_vita_core_3000(void) = 0;
 
     static sptr make(
         uhd::wb_iface::sptr iface,
+        const size_t base,
+        fc_monitor_loc fc_location = FC_PRE_RADIO
+    );
+
+    static sptr make_no_radio_buff(
+        uhd::wb_iface::sptr iface,
         const size_t base
     );
 
     virtual void clear(void) = 0;
 
-    virtual void set_tick_rate(const double rate) = 0;
-
     virtual void setup(const uhd::stream_args_t &stream_args) = 0;
 
     virtual void configure_flow_control(const size_t cycs_per_up, const size_t pkts_per_up) = 0;