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bufreg2: Split up dat_en to cnt_en and shift_en

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Olof Kindgren 2025-02-04 07:51:52 +01:00
parent 0a55885d3b
commit a38110aea9
1 changed files with 6 additions and 4 deletions
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10
rtl/serv_bufreg2.v
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@ -40,12 +40,14 @@ module serv_bufreg2
assign o_op_b = i_op_b_sel ? i_rs2 : i_imm;
wire dat_en = i_shift_op | (i_en & byte_valid);
wire shift_en = i_shift_op ? (i_en & i_init) : (i_en & byte_valid);
wire cnt_en = (i_shift_op & !i_init);
/* The dat register has three different use cases for store, load and
shift operations.
store : Data to be written is shifted to the correct position in dat during
init by dat_en and is presented on the data bus as o_wb_dat
init by shift_en and is presented on the data bus as o_wb_dat
load : Data from the bus gets latched into dat during i_wb_ack and is then
shifted out at the appropriate time to end up in the correct
position in rd
@ -54,7 +56,7 @@ module serv_bufreg2
o_sh_done when they wrap around to indicate that
the requested number of shifts have been performed
*/
wire [5:0] dat_shamt = (i_shift_op & !i_init) ?
wire [5:0] dat_shamt = cnt_en ?
//Down counter mode
dat[5:0]-1 :
//Shift reg mode with optional clearing of bit 5
@ -71,7 +73,7 @@ module serv_bufreg2
assign o_dat = dat;
always @(posedge i_clk) begin
if (dat_en | i_load)
if (shift_en | cnt_en | i_load)
dat <= i_load ? i_dat : {o_op_b, dat[31:7], dat_shamt};
end