| <!-- |
| Architecture with no fracturable LUTs |
| |
| - 40 nm technology |
| - General purpose logic block: |
| K = 6, N = 10 |
| - Routing architecture: L = 4, fc_in = 0.15, Fc_out = 0.1 |
| |
| Details on Modelling: |
| |
| Based on flagship k6_frac_N10_mem32K_40nm.xml architecture. This architecture has no fracturable LUTs nor any heterogeneous blocks. |
| |
| |
| Authors: Jason Luu, Jeff Goeders, Vaughn Betz |
| --> |
| <architecture> |
| <!-- |
| ODIN II specific config begins |
| Describes the types of user-specified netlist blocks (in blif, this corresponds to |
| ".model [type_of_block]") that this architecture supports. |
| |
| Note: Basic LUTs, I/Os, and flip-flops are not included here as there are |
| already special structures in blif (.names, .input, .output, and .latch) |
| that describe them. |
| --> |
| <models> |
| </models> |
| <tiles> |
| <tile name="io" capacity="8" area="0"> |
| <equivalent_sites> |
| <site pb_type="io"/> |
| </equivalent_sites> |
| <input name="outpad" num_pins="1"/> |
| <output name="inpad" num_pins="1"/> |
| <clock name="clock" num_pins="1"/> |
| <fc in_type="frac" in_val="0.15" out_type="frac" out_val="0.10"/> |
| <pinlocations pattern="custom"> |
| <loc side="left">io.outpad io.inpad io.clock</loc> |
| <loc side="top">io.outpad io.inpad io.clock</loc> |
| <loc side="right">io.outpad io.inpad io.clock</loc> |
| <loc side="bottom">io.outpad io.inpad io.clock</loc> |
| </pinlocations> |
| </tile> |
| <tile name="clb" area="53894"> |
| <equivalent_sites> |
| <site pb_type="clb"/> |
| </equivalent_sites> |
| <input name="I" num_pins="40" equivalent="full"/> |
| <output name="O" num_pins="10" equivalent="instance"/> |
| <clock name="clk" num_pins="1"/> |
| <fc in_type="frac" in_val="0.15" out_type="frac" out_val="0.10"/> |
| <pinlocations pattern="spread"/> |
| </tile> |
| </tiles> |
| <!-- ODIN II specific config ends --> |
| <!-- Physical descriptions begin --> |
| <layout> |
| <auto_layout aspect_ratio="1.0"> |
| <!--Perimeter of 'io' blocks with 'EMPTY' blocks at corners--> |
| <perimeter type="io" priority="100"/> |
| <corners type="EMPTY" priority="101"/> |
| <!--Fill with 'clb'--> |
| <fill type="clb" priority="10"/> |
| </auto_layout> |
| </layout> |
| <device> |
| <!-- VB & JL: Using Ian Kuon's transistor sizing and drive strength data for routing, at 40 nm. Ian used BPTM |
| models. We are modifying the delay values however, to include metal C and R, which allows more architecture |
| experimentation. We are also modifying the relative resistance of PMOS to be 1.8x that of NMOS |
| (vs. Ian's 3x) as 1.8x lines up with Jeff G's data from a 45 nm process (and is more typical of |
| 45 nm in general). I'm upping the Rmin_nmos from Ian's just over 6k to nearly 9k, and dropping |
| RminW_pmos from 18k to 16k to hit this 1.8x ratio, while keeping the delays of buffers approximately |
| lined up with Stratix IV. |
| We are using Jeff G.'s capacitance data for 45 nm (in tech/ptm_45nm). |
| Jeff's tables list C in for transistors with widths in multiples of the minimum feature size (45 nm). |
| The minimum contactable transistor is 2.5 * 45 nm, so I need to multiply drive strength sizes in this file |
| by 2.5x when looking up in Jeff's tables. |
| The delay values are lined up with Stratix IV, which has an architecture similar to this |
| proposed FPGA, and which is also 40 nm |
| C_ipin_cblock: input capacitance of a track buffer, which VPR assumes is a single-stage |
| 4x minimum drive strength buffer. --> |
| <sizing R_minW_nmos="8926" R_minW_pmos="16067"/> |
| <!-- The grid_logic_tile_area below will be used for all blocks that do not explicitly set their own (non-routing) |
| area; set to 0 since we explicitly set the area of all blocks currently in this architecture file. |
| --> |
| <area grid_logic_tile_area="0"/> |
| <chan_width_distr> |
| <x distr="uniform" peak="1.000000"/> |
| <y distr="uniform" peak="1.000000"/> |
| </chan_width_distr> |
| <switch_block type="wilton" fs="3"/> |
| <connection_block input_switch_name="ipin_cblock"/> |
| </device> |
| <switchlist> |
| <!-- VB: the mux_trans_size and buf_size data below is in minimum width transistor *areas*, assuming the purple |
| book area formula. This means the mux transistors are about 5x minimum drive strength. |
| We assume the first stage of the buffer is 3x min drive strength to be reasonable given the large |
| mux transistors, and this gives a reasonable stage ratio of a bit over 5x to the second stage. We assume |
| the n and p transistors in the first stage are equal-sized to lower the buffer trip point, since it's fed |
| by a pass transistor mux. We can then reverse engineer the buffer second stage to hit the specified |
| buf_size (really buffer area) - 16.2x minimum drive nmos and 1.8*16.2 = 29.2x minimum drive. |
| I then took the data from Jeff G.'s PTM modeling of 45 nm to get the Cin (gate of first stage) and Cout |
| (diff of second stage) listed below. Jeff's models are in tech/ptm_45nm, and are in min feature multiples. |
| The minimum contactable transistor is 2.5 * 45 nm, so I need to multiply the drive strength sizes above by |
| 2.5x when looking up in Jeff's tables. |
| Finally, we choose a switch delay (58 ps) that leads to length 4 wires having a delay equal to that of SIV of 126 ps. |
| This also leads to the switch being 46% of the total wire delay, which is reasonable. --> |
| <switch type="mux" name="0" R="551" Cin=".77e-15" Cout="4e-15" Tdel="58e-12" mux_trans_size="2.630740" buf_size="27.645901"/> |
| <!--switch ipin_cblock resistance set to yeild for 4x minimum drive strength buffer--> |
| <switch type="mux" name="ipin_cblock" R="2231.5" Cout="0." Cin="1.47e-15" Tdel="7.247000e-11" mux_trans_size="1.222260" buf_size="auto"/> |
| </switchlist> |
| <segmentlist> |
| <!--- VB & JL: using ITRS metal stack data, 96 nm half pitch wires, which are intermediate metal width/space. |
| With the 96 nm half pitch, such wires would take 60 um of height, vs. a 90 nm high (approximated as square) Stratix IV tile so this seems |
| reasonable. Using a tile length of 90 nm, corresponding to the length of a Stratix IV tile if it were square. --> |
| <segment freq="1.000000" length="4" type="unidir" Rmetal="101" Cmetal="22.5e-15"> |
| <mux name="0"/> |
| <sb type="pattern">1 1 1 1 1</sb> |
| <cb type="pattern">1 1 1 1</cb> |
| </segment> |
| </segmentlist> |
| <complexblocklist> |
| <!-- Define I/O pads begin --> |
| <!-- Capacity is a unique property of I/Os, it is the maximum number of I/Os that can be placed at the same (X,Y) location on the FPGA --> |
| <!-- Not sure of the area of an I/O (varies widely), and it's not relevant to the design of the FPGA core, so we're setting it to 0. --> |
| <pb_type name="io"> |
| <input name="outpad" num_pins="1"/> |
| <output name="inpad" num_pins="1"/> |
| <clock name="clock" num_pins="1"/> |
| <!-- IOs can operate as either inputs or outputs. |
| Delays below come from Ian Kuon. They are small, so they should be interpreted as |
| the delays to and from registers in the I/O (and generally I/Os are registered |
| today and that is when you timing analyze them. |
| --> |
| <mode name="inpad"> |
| <pb_type name="inpad" blif_model=".input" num_pb="1"> |
| <output name="inpad" num_pins="1"/> |
| </pb_type> |
| <interconnect> |
| <direct name="inpad" input="inpad.inpad" output="io.inpad"> |
| <delay_constant max="4.243e-11" in_port="inpad.inpad" out_port="io.inpad"/> |
| </direct> |
| </interconnect> |
| </mode> |
| <mode name="outpad"> |
| <pb_type name="outpad" blif_model=".output" num_pb="1"> |
| <input name="outpad" num_pins="1"/> |
| </pb_type> |
| <interconnect> |
| <direct name="outpad" input="io.outpad" output="outpad.outpad"> |
| <delay_constant max="1.394e-11" in_port="io.outpad" out_port="outpad.outpad"/> |
| </direct> |
| </interconnect> |
| </mode> |
| <!-- Every input pin is driven by 15% of the tracks in a channel, every output pin is driven by 10% of the tracks in a channel --> |
| <!-- IOs go on the periphery of the FPGA, for consistency, |
| make it physically equivalent on all sides so that only one definition of I/Os is needed. |
| If I do not make a physically equivalent definition, then I need to define 4 different I/Os, one for each side of the FPGA |
| --> |
| <!-- Place I/Os on the sides of the FPGA --> |
| <power method="ignore"/> |
| </pb_type> |
| <!-- Define I/O pads ends --> |
| <!-- Define general purpose logic block (CLB) begin --> |
| <!--- Area calculation: Total Stratix IV tile area is about 8100 um^2, and a minimum width transistor |
| area is 60 L^2 yields a tile area of 84375 MWTAs. |
| Routing at W=300 is 30481 MWTAs, leaving us with a total of 53000 MWTAs for logic block area |
| This means that only 37% of our area is in the general routing, and 63% is inside the logic |
| block. Note that the crossbar / local interconnect is considered part of the logic block |
| area in this analysis. That is a lower proportion of of routing area than most academics |
| assume, but note that the total routing area really includes the crossbar, which would push |
| routing area up significantly, we estimate into the ~70% range. |
| --> |
| <pb_type name="clb"> |
| <input name="I" num_pins="40" equivalent="full"/> |
| <output name="O" num_pins="10" equivalent="instance"/> |
| <clock name="clk" num_pins="1"/> |
| <!-- Describe basic logic element. |
| Each basic logic element has a 6-LUT that can be optionally registered |
| --> |
| <pb_type name="fle" num_pb="10"> |
| <input name="in" num_pins="6"/> |
| <output name="out" num_pins="1"/> |
| <clock name="clk" num_pins="1"/> |
| <!-- 6-LUT mode definition begin --> |
| <mode name="n1_lut6"> |
| <!-- Define 6-LUT mode --> |
| <pb_type name="ble6" num_pb="1"> |
| <input name="in" num_pins="6"/> |
| <output name="out" num_pins="1"/> |
| <clock name="clk" num_pins="1"/> |
| <!-- Define LUT --> |
| <pb_type name="lut6" blif_model=".names" num_pb="1" class="lut"> |
| <input name="in" num_pins="6" port_class="lut_in"/> |
| <output name="out" num_pins="1" port_class="lut_out"/> |
| <!-- LUT timing using delay matrix --> |
| <!-- These are the physical delay inputs on a Stratix IV LUT but because VPR cannot do LUT rebalancing, |
| we instead take the average of these numbers to get more stable results |
| 82e-12 |
| 173e-12 |
| 261e-12 |
| 263e-12 |
| 398e-12 |
| 397e-12 |
| --> |
| <delay_matrix type="max" in_port="lut6.in" out_port="lut6.out"> |
| 261e-12 |
| 261e-12 |
| 261e-12 |
| 261e-12 |
| 261e-12 |
| 261e-12 |
| </delay_matrix> |
| </pb_type> |
| <!-- Define flip-flop --> |
| <pb_type name="ff" blif_model=".latch" num_pb="1" class="flipflop"> |
| <input name="D" num_pins="1" port_class="D"/> |
| <output name="Q" num_pins="1" port_class="Q"/> |
| <clock name="clk" num_pins="1" port_class="clock"/> |
| <T_setup value="66e-12" port="ff.D" clock="clk"/> |
| <T_clock_to_Q max="124e-12" port="ff.Q" clock="clk"/> |
| </pb_type> |
| <interconnect> |
| <direct name="direct1" input="ble6.in" output="lut6[0:0].in"/> |
| <direct name="direct2" input="lut6.out" output="ff.D"> |
| <!-- Advanced user option that tells CAD tool to find LUT+FF pairs in netlist --> |
| <pack_pattern name="ble6" in_port="lut6.out" out_port="ff.D"/> |
| </direct> |
| <direct name="direct3" input="ble6.clk" output="ff.clk"/> |
| <mux name="mux1" input="ff.Q lut6.out" output="ble6.out"> |
| <!-- LUT to output is faster than FF to output on a Stratix IV --> |
| <delay_constant max="25e-12" in_port="lut6.out" out_port="ble6.out"/> |
| <delay_constant max="45e-12" in_port="ff.Q" out_port="ble6.out"/> |
| </mux> |
| </interconnect> |
| </pb_type> |
| <interconnect> |
| <direct name="direct1" input="fle.in" output="ble6.in"/> |
| <direct name="direct2" input="ble6.out" output="fle.out[0:0]"/> |
| <direct name="direct3" input="fle.clk" output="ble6.clk"/> |
| </interconnect> |
| </mode> |
| <!-- 6-LUT mode definition end --> |
| </pb_type> |
| <interconnect> |
| <!-- We use a full crossbar to get logical equivalence at inputs of CLB |
| The delays below come from Stratix IV. the delay through a connection block |
| input mux + the crossbar in Stratix IV is 167 ps. We already have a 72 ps |
| delay on the connection block input mux (modeled by Ian Kuon), so the remaining |
| delay within the crossbar is 95 ps. |
| The delays of cluster feedbacks in Stratix IV is 100 ps, when driven by a LUT. |
| Since all our outputs LUT outputs go to a BLE output, and have a delay of |
| 25 ps to do so, we subtract 25 ps from the 100 ps delay of a feedback |
| to get the part that should be marked on the crossbar. --> |
| <complete name="crossbar" input="clb.I fle[9:0].out" output="fle[9:0].in"> |
| <delay_constant max="95e-12" in_port="clb.I" out_port="fle[9:0].in"/> |
| <delay_constant max="75e-12" in_port="fle[9:0].out" out_port="fle[9:0].in"/> |
| </complete> |
| <complete name="clks" input="clb.clk" output="fle[9:0].clk"> |
| </complete> |
| <!-- This way of specifying direct connection to clb outputs is important because this architecture uses automatic spreading of opins. |
| By grouping to output pins in this fashion, if a logic block is completely filled by 6-LUTs, |
| then the outputs those 6-LUTs take get evenly distributed across all four sides of the CLB instead of clumped on two sides (which is what happens with a more |
| naive specification). |
| --> |
| <direct name="clbouts1" input="fle[9:0].out" output="clb.O"/> |
| </interconnect> |
| <!-- Every input pin is driven by 15% of the tracks in a channel, every output pin is driven by 10% of the tracks in a channel --> |
| <!-- Place this general purpose logic block in any unspecified column --> |
| </pb_type> |
| <!-- Define general purpose logic block (CLB) ends --> |
| </complexblocklist> |
| <power> |
| <local_interconnect C_wire="2.5e-10"/> |
| <mux_transistor_size mux_transistor_size="3"/> |
| <FF_size FF_size="4"/> |
| <LUT_transistor_size LUT_transistor_size="4"/> |
| </power> |
| <clocks> |
| <clock buffer_size="auto" C_wire="2.5e-10"/> |
| </clocks> |
| </architecture> |