Merge branch 'maint'

4 files changed, 55 insertions, 25 deletions

diff --git a/host/lib/usrp/x300/x300_fw_uart.cpp b/host/lib/usrp/x300/x300_fw_uart.cpp
index 6e7425c4d..a2cbcc908 100644
--- a/host/lib/usrp/x300/x300_fw_uart.cpp
+++ b/host/lib/usrp/x300/x300_fw_uart.cpp
@@ -76,8 +76,9 @@ struct x300_uart_iface : uart_iface
         if (rxoffset == _last_device_rxoffset)
             return -1;
 
+        int ret = static_cast<int>(_rxcache[((rxoffset)/4) % poolsize] >> ((rxoffset%4)*8) & 0xFF);
         rxoffset++;
-        return static_cast<int>(_rxcache[(rxoffset/4) % poolsize] >> ((rxoffset%4)*8) & 0xFF);
+        return ret;
     }
 
     void update_cache(void)
@@ -91,30 +92,42 @@ struct x300_uart_iface : uart_iface
             {
                 // all the data is new - reload the entire cache
                 for (uint32_t i = 0; i < poolsize; i++)
+                {
                     _rxcache[i] = _iface->peek32(SR_ADDR(rxpool, i));
+                }
+
+                // set the head to the same character as the current device
+                // offset (tail) one loop earlier
+                rxoffset = device_rxoffset - (poolsize*4);
+
+                // set the tail to the current device offset
+                _last_device_rxoffset = device_rxoffset;
 
-                // set rxoffset to the end of the first string
-                rxoffset = device_rxoffset - (poolsize*4) + 1;
-                while (static_cast<char>((_rxcache[(rxoffset/4) % poolsize] >> ((rxoffset%4)*8) & 0xFF)) != '\n')
-                    ++rxoffset;
+                // the string at the head is a partial, so skip it
+                for (int c = getchar(); c != '\n' and c != -1; c = getchar()) {}
 
-                // clear the partial string in the buffer;
+                // clear the partial string in the buffer, if any
                 _rxbuff.clear();
             }
             else if (rxoffset == _last_device_rxoffset)
             {
                 // new data was added - refresh the portion of the cache that was updated
-                for (uint32_t i = ((_last_device_rxoffset+1)/4) % poolsize; i != (((device_rxoffset)/4)+1) % poolsize; i = (i+1) % poolsize)
+                for (uint32_t i = (_last_device_rxoffset/4) % poolsize;
+                        i != ((device_rxoffset/4)+1) % poolsize;
+                        i = (i+1) % poolsize)
                 {
                     _rxcache[i] = _iface->peek32(SR_ADDR(rxpool, i));
                 }
-            } else {
+
+                // set the tail to the current device offset
+                _last_device_rxoffset = device_rxoffset;
+            }
+            else
+            {
                 // there is new data, but we aren't done with what we have - check back later
                 break;
             }
 
-            _last_device_rxoffset = device_rxoffset;
-
             // check again to see if anything changed while we were updating the cache
             device_rxoffset = _iface->peek32(SR_ADDR(X300_FW_SHMEM_BASE, X300_FW_SHMEM_UART_RX_INDEX));
             delta = device_rxoffset - rxoffset;
diff --git a/host/lib/usrp/x300/x300_impl.cpp b/host/lib/usrp/x300/x300_impl.cpp
index 8164c79b6..aa54c2228 100644
--- a/host/lib/usrp/x300/x300_impl.cpp
+++ b/host/lib/usrp/x300/x300_impl.cpp
@@ -1529,13 +1529,32 @@ void x300_impl::claimer_loop(wb_iface::sptr iface)
 
 x300_impl::claim_status_t x300_impl::claim_status(wb_iface::sptr iface)
 {
-    //If timed out, then device is definitely unclaimed
-    if (iface->peek32(X300_FW_SHMEM_ADDR(X300_FW_SHMEM_CLAIM_STATUS)) == 0)
-        return UNCLAIMED;
+    claim_status_t claim_status = CLAIMED_BY_OTHER; // Default to most restrictive
+    boost::system_time timeout_time = boost::get_system_time() + boost::posix_time::seconds(1);
+    while (boost::get_system_time() < timeout_time)
+    {
+        //If timed out, then device is definitely unclaimed
+        if (iface->peek32(X300_FW_SHMEM_ADDR(X300_FW_SHMEM_CLAIM_STATUS)) == 0)
+        {
+            claim_status = UNCLAIMED;
+            break;
+        }
 
-    //otherwise check claim src to determine if another thread with the same src has claimed the device
-    uint32_t hash = iface->peek32(X300_FW_SHMEM_ADDR(X300_FW_SHMEM_CLAIM_SRC));
-    return (hash == get_process_hash() ? CLAIMED_BY_US : CLAIMED_BY_OTHER);
+        //otherwise check claim src to determine if another thread with the same src has claimed the device
+        uint32_t hash = iface->peek32(X300_FW_SHMEM_ADDR(X300_FW_SHMEM_CLAIM_SRC));
+        if (hash == 0)
+        {
+            // A non-zero claim status and an empty hash means the claim might
+            // be in the process of being released.  This is possible because
+            // older firmware takes a long time to update the status.  Wait and
+            // check status again.
+            boost::this_thread::sleep(boost::posix_time::milliseconds(5));
+            continue;
+        }
+        claim_status = (hash == get_process_hash() ? CLAIMED_BY_US : CLAIMED_BY_OTHER);
+        break;
+    }
+    return claim_status;
 }
 
 void x300_impl::claim(wb_iface::sptr iface)
diff --git a/host/lib/usrp/x300/x300_impl.hpp b/host/lib/usrp/x300/x300_impl.hpp
index 55b055d44..d082ab76a 100644
--- a/host/lib/usrp/x300/x300_impl.hpp
+++ b/host/lib/usrp/x300/x300_impl.hpp
@@ -54,10 +54,7 @@ static const size_t X300_RX_SW_BUFF_SIZE_ETH_MACOS  = 0x100000; //1Mib
 //where an element is 8 bytes. For best throughput ensure that the data frame fits in these buffers.
 //Also ensure that the kernel has enough frames to hold buffered TX and RX data
 static const size_t X300_PCIE_RX_DATA_FRAME_SIZE    = 8184;     //bytes
-//static const size_t X300_PCIE_TX_DATA_FRAME_SIZE    = 8192;     //bytes
-// This is a temporary solution: We're throttling PCIe MTU to avoid
-// underruns on Tx. Once we solve it on the FPGA side, need revert this commit.
-static const size_t X300_PCIE_TX_DATA_FRAME_SIZE    = 3000;     //bytes
+static const size_t X300_PCIE_TX_DATA_FRAME_SIZE    = 8184;     //bytes
 static const size_t X300_PCIE_DATA_NUM_FRAMES       = 2048;
 static const size_t X300_PCIE_MSG_FRAME_SIZE        = 256;      //bytes
 static const size_t X300_PCIE_MSG_NUM_FRAMES        = 64;
diff --git a/host/lib/usrp/x300/x300_radio_ctrl_impl.cpp b/host/lib/usrp/x300/x300_radio_ctrl_impl.cpp
index f4ad0d035..9bf61f998 100644
--- a/host/lib/usrp/x300/x300_radio_ctrl_impl.cpp
+++ b/host/lib/usrp/x300/x300_radio_ctrl_impl.cpp
@@ -126,8 +126,7 @@ UHD_RFNOC_RADIO_BLOCK_CONSTRUCTOR(x300_radio_ctrl)
         // Bind the daughterboard command time to the motherboard level property
         ////////////////////////////////////////////////////////////////
 
-        if (_tree->exists(fs_path("time") / "cmd") and
-                _tree->exists(fs_path("dboards" / _radio_slot /  "rx_frontends" / _rx_fe_map.at(i).db_fe_name / "time" / "cmd"))) {
+        if (_tree->exists(fs_path("time") / "cmd")) {
             _tree->access<time_spec_t>(fs_path("time") / "cmd")
                 .add_coerced_subscriber(boost::bind(&x300_radio_ctrl_impl::set_fe_cmd_time, this, _1, i));
         }
@@ -180,9 +179,11 @@ double x300_radio_ctrl_impl::set_rate(double rate)
 
 void x300_radio_ctrl_impl::set_fe_cmd_time(const time_spec_t &time, const size_t chan)
 {
-    _tree->access<time_spec_t>(
-            fs_path("dboards" / _radio_slot /  "rx_frontends" / _rx_fe_map.at(chan).db_fe_name / "time" / "cmd")
-    ).set(time);
+    if (_tree->exists(fs_path("dboards" / _radio_slot /  "rx_frontends" / _rx_fe_map.at(chan).db_fe_name / "time" / "cmd"))) {
+        _tree->access<time_spec_t>(
+                fs_path("dboards" / _radio_slot /  "rx_frontends" / _rx_fe_map.at(chan).db_fe_name / "time" / "cmd")
+        ).set(time);
+    }
 }
 
 void x300_radio_ctrl_impl::set_tx_antenna(const std::string &ant, const size_t chan)