diff options
| author | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2008-09-08 01:00:12 +0000 |
|---|---|---|
| committer | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2008-09-08 01:00:12 +0000 |
| commit | e0fcbaee124d3e8c4c11bdda662f88e082352058 (patch) | |
| tree | a51ef1c8b949681f45e5664478e8515065cfff5b /usrp2/fpga/control_lib/wb_semaphore.v | |
| parent | c86f6c23c6883f73d953d64c28ab42cedb77e4d7 (diff) | |
Merged r9433:9527 from features/gr-usrp2 into trunk. Adds usrp2 and gr-usrp2 top-level components. Trunk passes distcheck with mb-gcc installed, but currently not without them. The key issue is that when mb-gcc is not installed, the build system skips over the usrp2/firmware directory, and the firmware include files don't get put into the dist tarball. But we can't do the usual DIST_SUBDIRS method as the firmware is a subpackage.
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@9528 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'usrp2/fpga/control_lib/wb_semaphore.v')
| -rw-r--r-- | usrp2/fpga/control_lib/wb_semaphore.v | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/usrp2/fpga/control_lib/wb_semaphore.v b/usrp2/fpga/control_lib/wb_semaphore.v new file mode 100644 index 0000000000..a9208e6a17 --- /dev/null +++ b/usrp2/fpga/control_lib/wb_semaphore.v @@ -0,0 +1,42 @@ + +// up to 8 semaphores + +// After a read operation, the semaphore is always locked +// If it was already locked before the read (meaning someone else holds the lock) +// then a 1 is returned +// If it was not already locked (meaning the reader now holds the lock) +// then a 0 is returned + +// A write operation clears the lock + +module wb_semaphore + #(parameter count=8, DBUS_WIDTH=32) + (input wb_clk_i, + input wb_rst_i, + input [DBUS_WIDTH-1:0] wb_dat_i, + input [2:0] wb_adr_i, + input wb_cyc_i, + input wb_stb_i, + input wb_we_i, + output wb_ack_o, + output [DBUS_WIDTH-1:0] wb_dat_o); + + reg [count-1:0] locked; + + always @(posedge clock) + if(wb_rst_i) + locked <= {count{1'b0}}; + else if(wb_stb_i) + if(wb_we_i) + locked[adr_i] <= 1'b0; + else + locked[adr_i] <= 1'b1; + + assign wb_dat_o[DBUS_WIDTH-1:1] = {(DBUS_WIDTH-1){1'b0}}; + assign wb_dat_o[0] = locked[adr_i]; + assign wb_ack_o = wb_stb_i; + + +endmodule // wb_semaphore + + |