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author | David Shah <davey1576@gmail.com> | 2017-11-13 16:15:16 +0000 |
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committer | David Shah <davey1576@gmail.com> | 2017-11-17 15:08:58 +0000 |
commit | 64e3c1a9cd81e61d9a3b163c9e9f9390fa4c5c21 (patch) | |
tree | df2fde90d49ad463b7551ea3e8dfcd707f135e27 /docs | |
parent | 88eebff7db9d76e418ccbddd884c4e617596a428 (diff) | |
download | icestorm-64e3c1a9cd81e61d9a3b163c9e9f9390fa4c5c21.tar.gz icestorm-64e3c1a9cd81e61d9a3b163c9e9f9390fa4c5c21.tar.bz2 icestorm-64e3c1a9cd81e61d9a3b163c9e9f9390fa4c5c21.zip |
Figure out DSP config bits for all locs
Diffstat (limited to 'docs')
-rw-r--r-- | docs/ultraplus.html | 45 |
1 files changed, 42 insertions, 3 deletions
diff --git a/docs/ultraplus.html b/docs/ultraplus.html index 86fd857..4220cad 100644 --- a/docs/ultraplus.html +++ b/docs/ultraplus.html @@ -109,9 +109,48 @@ A work-in-progress effort to determine where signals and configuration bits are to DSP1 <span style="font-family:monospace">CBIT[7:0]</span>, <span style="font-family:monospace">CBIT[23:16]</span> to DSP2 <span style="font-family:monospace">CBIT[7:0]</span> and <span style="font-family:monospace">CBIT[24]</span> to DSP3 <span style="font-family:monospace">CBIT0</span>. </p> -<p>However, there are some locations where configuration bits are swapped between DSP tiles and IPConnect tiles. For example, DSP1 (0, 16) <span style="font-family:monospace">CBIT[4:3]</span> is used - for the internal oscillator, and the DSP configuration bits are then located in IPConnect tile (0, 19) <span style="font-family:monospace">CBIT[6:5]</span>.</p> -<p>The exact permutations are not yet known, but a script will be developed to find them.</p> +<p>However, there is one location where configuration bits are swapped between DSP tiles and IPConnect tiles. In DSP1 (0, 16) <span style="font-family:monospace">CBIT[4:1]</span> are used + for IP such as the internal oscillator, and the DSP configuration bits are then located in IPConnect tile (0, 19) <span style="font-family:monospace">CBIT[6:3]</span>.</p> +<p>The full list of configuration bits, including the changes for the DSP at (0, 15) are described in the table below.</p> + +<table class="ctab"> +<tr><th>Parameter</th><th>Normal Position</th><th>DSP (0, 15)<br/>Changes</th></tr> +<tr><td>C_REG</td><td>DSP0.CBIT_0</td><td></td></tr> +<tr><td>A_REG</td><td>DSP0.CBIT_1</td><td></td></tr> +<tr><td>B_REG</td><td>DSP0.CBIT_2</td><td></td></tr> +<tr><td>D_REG</td><td>DSP0.CBIT_3</td><td></td></tr> + +<tr><td>TOP_8x8_MULT_REG</td><td>DSP0.CBIT_4</td><td></td></tr> +<tr><td>BOT_8x8_MULT_REG</td><td>DSP0.CBIT_5</td><td></td></tr> + +<tr><td>PIPELINE_16x16_MULT_REG1</td><td>DSP0.CBIT_6</td><td></td></tr> +<tr><td>PIPELINE_16x16_MULT_REG2</td><td>DSP0.CBIT_7</td><td></td></tr> + +<tr><td>TOPOUTPUT_SELECT[0]</td><td>DSP1.CBIT_0</td><td></td></tr> +<tr><td>TOPOUTPUT_SELECT[1]</td><td>DSP1.CBIT_1</td><td>(0, 19).CBIT_3</td></tr> + +<tr><td>TOPADDSUB_LOWERINPUT[1:0]</td><td>DSP1.CBIT_[3:2]</td><td>(0, 19).CBIT_[5:4]</td></tr> +<tr><td>TOPADDSUB_UPPERINUT</td><td>DSP1.CBIT_4</td><td>(0, 19).CBIT_6</td></tr> +<tr><td>TOPADDSUB_CARRYSELECT[1:0]</td><td>DSP1.CBIT_[6:5]</td><td></td></tr> + +<tr><td>BOTOUTPUT_SELECT[0]</td><td>DSP1.CBIT_7</td><td></td></tr> +<tr><td>BOTOUTPUT_SELECT[1]</td><td>DSP2.CBIT_0</td><td></td></tr> + +<tr><td>BOTADDSUB_LOWERINPUT[1:0]</td><td>DSP2.CBIT_[2:1]</td><td></td></tr> +<tr><td>BOTADDSUB_UPPERINPUT</td><td>DSP2.CBIT_3</td><td></td></tr> +<tr><td>BOTADDSUB_CARRYSELECT</td><td>DSP2.CBIT_[5:4]</td><td></td></tr> + +<tr><td>MODE_8x8</td><td>DSP2.CBIT_6</td><td></td></tr> + +<tr><td>A_SIGNED</td><td>DSP2.CBIT_7</td><td></td></tr> +<tr><td>B_SIGNED</td><td>DSP3.CBIT_0</td><td></td></tr> + +</table> + +<p>Lattice document a limited number of supported configurations in the ICE Technology Library document, and Lattice's EDIF parser will + reject designs not following a supported configuration. It is not yet known whether unsupported configurations (such as mixed + signed and unsigned) function correctly or not. + <p> <strong>Other Implementation Notes</strong><br/> <p> |