b100: use frame boundary to calculate frame size

2 files changed, 6 insertions, 4 deletions

diff --git a/host/lib/transport/usb_zero_copy_wrapper.cpp b/host/lib/transport/usb_zero_copy_wrapper.cpp
index 07105cad3..690e5aaa2 100644
--- a/host/lib/transport/usb_zero_copy_wrapper.cpp
+++ b/host/lib/transport/usb_zero_copy_wrapper.cpp
@@ -112,6 +112,7 @@ class usb_zero_copy_wrapper : public usb_zero_copy{
 public:
     usb_zero_copy_wrapper(sptr usb_zc, const size_t frame_boundary):
         _internal_zc(usb_zc),
+        _frame_boundary(frame_boundary),
         _available_recv_buffs(this->get_num_recv_frames()),
         _mrb_pool(this->get_num_recv_frames(), usb_zero_copy_wrapper_mrb(_available_recv_buffs)),
         _the_only_msb(usb_zero_copy_wrapper_msb(usb_zc, frame_boundary))
@@ -157,7 +158,7 @@ public:
     }
 
     size_t get_recv_frame_size(void) const{
-        return _internal_zc->get_recv_frame_size();
+        return std::min(_frame_boundary, _internal_zc->get_recv_frame_size());
     }
 
     managed_send_buffer::sptr get_send_buff(double timeout){
@@ -169,11 +170,12 @@ public:
     }
 
     size_t get_send_frame_size(void) const{
-        return _internal_zc->get_send_frame_size();
+        return std::min(_frame_boundary, _internal_zc->get_send_frame_size());
     }
 
 private:
     sptr _internal_zc;
+    size_t _frame_boundary;
     bounded_buffer<usb_zero_copy_wrapper_mrb *> _available_recv_buffs;
     std::vector<usb_zero_copy_wrapper_mrb> _mrb_pool;
     usb_zero_copy_wrapper_msb _the_only_msb;
diff --git a/host/lib/usrp/b100/io_impl.cpp b/host/lib/usrp/b100/io_impl.cpp
index d7effcac1..6f8d3fb52 100644
--- a/host/lib/usrp/b100/io_impl.cpp
+++ b/host/lib/usrp/b100/io_impl.cpp
@@ -206,7 +206,7 @@ rx_streamer::sptr b100_impl::get_rx_stream(const uhd::stream_args_t &args_){
         - sizeof(vrt::if_packet_info_t().cid) //no class id ever used
         - sizeof(vrt::if_packet_info_t().tsi) //no int time ever used
     ;
-    const size_t bpp = B100_MAX_PKT_BYTE_LIMIT - hdr_size;
+    const size_t bpp = _data_transport->get_recv_frame_size() - hdr_size;
     const size_t bpi = convert::get_bytes_per_item(args.otw_format);
     const size_t spp = unsigned(args.args.cast<double>("spp", bpp/bpi));
 
@@ -263,7 +263,7 @@ tx_streamer::sptr b100_impl::get_tx_stream(const uhd::stream_args_t &args_){
         - sizeof(vrt::if_packet_info_t().cid) //no class id ever used
         - sizeof(vrt::if_packet_info_t().tsi) //no int time ever used
     ;
-    static const size_t bpp = B100_MAX_PKT_BYTE_LIMIT - hdr_size;
+    static const size_t bpp = _data_transport->get_send_frame_size() - hdr_size;
     const size_t spp = bpp/convert::get_bytes_per_item(args.otw_format);
 
     //make the new streamer given the samples per packet