Add support for RV32E #695
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Signed-off-by: Oivind Ekelund <[email protected]>
Silabs-ArjanB
added
the
Component:RTL
rtl/cv32e40x_id_stage.sv
Outdated
| @@ -739,16 +746,20 @@ module cv32e40x_id_stage import cv32e40x_pkg::*; | |||
| xif_issue_if.issue_req.rs_valid = '0; | |||
| if (xif_issue_if.X_NUM_RS > 0) begin | |||
| xif_issue_if.issue_req.rs [0] = operand_a_fw; | |||
| xif_issue_if.issue_req.rs_valid[0] = 1'b1; | |||
| xif_issue_if.issue_req.rs_valid[0] = (ctrl_byp_i.operand_a_fw_mux_sel == SEL_REGFILE) ? | |||
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Why do we need the select based on ctrl_byp_i.operand_a_fw_mux_sel == SEL_REGFILE?
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Because values can be forwarded from EX or WB stage. Upon forwarding, the RF address check in the decode stage will not be applicable.
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I would say that the RF address check from the decoder stage would always apply, so it should be:
xif_issue_if.issue_req.rs_valid[0] = !rf_illegal_raddr[0];
(Of course in reality ctrl_byp_i.operand_a_fw_mux_sel == SEL_REGFILE will always hold and then your code proposal and my proposal are the same. Also note that stalls/bypass usage is not correct yet, see #277)
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Of course, you're right. Updated.
…ch sub-decoder Signed-off-by: Oivind Ekelund <[email protected]>
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| assign dec_a_rf_illegal_addr = (decoder_a_ctrl_int.rf_re[0] && rf_illegal_raddr_o[0]) || |
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Assign this signal to 1'b0 in 'else' part of generate statement so that we do net get floating signals (even though they are not used). Same remark for other similar signals.
rtl/cv32e40x_id_stage.sv
Outdated
| @@ -739,16 +746,20 @@ module cv32e40x_id_stage import cv32e40x_pkg::*; | |||
| xif_issue_if.issue_req.rs_valid = '0; | |||
| if (xif_issue_if.X_NUM_RS > 0) begin | |||
| xif_issue_if.issue_req.rs [0] = operand_a_fw; | |||
| xif_issue_if.issue_req.rs_valid[0] = 1'b1; | |||
| xif_issue_if.issue_req.rs_valid[0] = (ctrl_byp_i.operand_a_fw_mux_sel == SEL_REGFILE) ? | |||
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I would say that the RF address check from the decoder stage would always apply, so it should be:
xif_issue_if.issue_req.rs_valid[0] = !rf_illegal_raddr[0];
(Of course in reality ctrl_byp_i.operand_a_fw_mux_sel == SEL_REGFILE will always hold and then your code proposal and my proposal are the same. Also note that stalls/bypass usage is not correct yet, see #277)
… generation. Signed-off-by: Oivind Ekelund <[email protected]>
SEC clean when parameter RV32=RV32I
Signed-off-by: Oivind Ekelund [email protected]