2 use ieee.std_logic_1164.all;
3 use ieee.numeric_std.all;
6 use work.decode_types.all;
9 use work.insn_helpers.all;
13 EX1_BYPASS : boolean := true;
14 -- Non-zero to enable log data collection
15 LOG_LENGTH : natural := 0
21 complete_in : in std_ulogic;
22 busy_in : in std_ulogic;
23 stall_out : out std_ulogic;
25 stopped_out : out std_ulogic;
27 flush_in: in std_ulogic;
29 d_in : in Decode1ToDecode2Type;
31 e_out : out Decode2ToExecute1Type;
33 r_in : in RegisterFileToDecode2Type;
34 r_out : out Decode2ToRegisterFileType;
36 c_in : in CrFileToDecode2Type;
37 c_out : out Decode2ToCrFileType;
39 log_out : out std_ulogic_vector(9 downto 0)
43 architecture behaviour of decode2 is
44 type reg_type is record
45 e : Decode2ToExecute1Type;
48 signal r, rin : reg_type;
50 signal deferred : std_ulogic;
52 type decode_input_reg_t is record
53 reg_valid : std_ulogic;
55 data : std_ulogic_vector(63 downto 0);
58 type decode_output_reg_t is record
59 reg_valid : std_ulogic;
63 function decode_input_reg_a (t : input_reg_a_t; insn_in : std_ulogic_vector(31 downto 0);
64 reg_data : std_ulogic_vector(63 downto 0);
66 instr_addr : std_ulogic_vector(63 downto 0))
67 return decode_input_reg_t is
69 if t = RA or (t = RA_OR_ZERO and insn_ra(insn_in) /= "00000") then
70 return ('1', gpr_to_gspr(insn_ra(insn_in)), reg_data);
72 -- ISPR must be either a valid fast SPR number or all 0 for a slow SPR.
73 -- If it's all 0, we don't treat it as a dependency as slow SPRs
74 -- operations are single issue.
76 assert is_fast_spr(ispr) = '1' or ispr = "000000"
77 report "Decode A says SPR but ISPR is invalid:" &
78 to_hstring(ispr) severity failure;
79 return (is_fast_spr(ispr), ispr, reg_data);
81 return ('0', (others => '0'), instr_addr);
83 return ('0', (others => '0'), (others => '0'));
87 function decode_input_reg_b (t : input_reg_b_t; insn_in : std_ulogic_vector(31 downto 0);
88 reg_data : std_ulogic_vector(63 downto 0);
89 ispr : gspr_index_t) return decode_input_reg_t is
90 variable ret : decode_input_reg_t;
94 ret := ('1', gpr_to_gspr(insn_rb(insn_in)), reg_data);
96 ret := ('0', (others => '0'), std_ulogic_vector(resize(unsigned(insn_ui(insn_in)), 64)));
98 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_si(insn_in)), 64)));
100 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_si(insn_in)) & x"0000", 64)));
102 ret := ('0', (others => '0'), std_ulogic_vector(resize(unsigned(insn_si(insn_in)) & x"0000", 64)));
104 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_li(insn_in)) & "00", 64)));
106 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_bd(insn_in)) & "00", 64)));
108 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_ds(insn_in)) & "00", 64)));
110 ret := ('0', (others => '0'), std_ulogic_vector(resize(signed(insn_dx(insn_in)) & x"0004", 64)));
112 ret := ('0', (others => '0'), x"FFFFFFFFFFFFFFFF");
114 ret := ('0', (others => '0'), x"00000000000000" & "00" & insn_in(1) & insn_in(15 downto 11));
116 ret := ('0', (others => '0'), x"00000000000000" & "000" & insn_in(15 downto 11));
118 -- ISPR must be either a valid fast SPR number or all 0 for a slow SPR.
119 -- If it's all 0, we don't treat it as a dependency as slow SPRs
120 -- operations are single issue.
121 assert is_fast_spr(ispr) = '1' or ispr = "000000"
122 report "Decode B says SPR but ISPR is invalid:" &
123 to_hstring(ispr) severity failure;
124 ret := (is_fast_spr(ispr), ispr, reg_data);
126 ret := ('0', (others => '0'), (others => '0'));
132 function decode_input_reg_c (t : input_reg_c_t; insn_in : std_ulogic_vector(31 downto 0);
133 reg_data : std_ulogic_vector(63 downto 0)) return decode_input_reg_t is
137 return ('1', gpr_to_gspr(insn_rs(insn_in)), reg_data);
139 return ('1', gpr_to_gspr(insn_rcreg(insn_in)), reg_data);
141 return ('0', (others => '0'), (others => '0'));
145 function decode_output_reg (t : output_reg_a_t; insn_in : std_ulogic_vector(31 downto 0);
146 ispr : gspr_index_t) return decode_output_reg_t is
150 return ('1', gpr_to_gspr(insn_rt(insn_in)));
152 return ('1', gpr_to_gspr(insn_ra(insn_in)));
154 -- ISPR must be either a valid fast SPR number or all 0 for a slow SPR.
155 -- If it's all 0, we don't treat it as a dependency as slow SPRs
156 -- operations are single issue.
157 assert is_fast_spr(ispr) = '1' or ispr = "000000"
158 report "Decode B says SPR but ISPR is invalid:" &
159 to_hstring(ispr) severity failure;
160 return (is_fast_spr(ispr), ispr);
162 return ('0', "000000");
166 function decode_rc (t : rc_t; insn_in : std_ulogic_vector(31 downto 0)) return std_ulogic is
170 return insn_rc(insn_in);
178 -- For now, use "rc" in the decode table to decide whether oe exists.
179 -- This is not entirely correct architecturally: For mulhd and
180 -- mulhdu, the OE field is reserved. It remains to be seen what an
181 -- actual POWER9 does if we set it on those instructions, for now we
182 -- test that further down when assigning to the multiplier oe input.
184 function decode_oe (t : rc_t; insn_in : std_ulogic_vector(31 downto 0)) return std_ulogic is
188 return insn_oe(insn_in);
194 -- issue control signals
195 signal control_valid_in : std_ulogic;
196 signal control_valid_out : std_ulogic;
197 signal control_sgl_pipe : std_logic;
199 signal gpr_write_valid : std_ulogic;
200 signal gpr_write : gspr_index_t;
201 signal gpr_bypassable : std_ulogic;
203 signal update_gpr_write_valid : std_ulogic;
204 signal update_gpr_write_reg : gspr_index_t;
206 signal gpr_a_read_valid : std_ulogic;
207 signal gpr_a_read :gspr_index_t;
208 signal gpr_a_bypass : std_ulogic;
210 signal gpr_b_read_valid : std_ulogic;
211 signal gpr_b_read : gspr_index_t;
212 signal gpr_b_bypass : std_ulogic;
214 signal gpr_c_read_valid : std_ulogic;
215 signal gpr_c_read : gpr_index_t;
216 signal gpr_c_bypass : std_ulogic;
218 signal cr_write_valid : std_ulogic;
219 signal cr_bypass : std_ulogic;
220 signal cr_bypass_avail : std_ulogic;
223 control_0: entity work.control
231 complete_in => complete_in,
232 valid_in => control_valid_in,
234 deferred => deferred,
235 flush_in => flush_in,
236 sgl_pipe_in => control_sgl_pipe,
237 stop_mark_in => d_in.stop_mark,
239 gpr_write_valid_in => gpr_write_valid,
240 gpr_write_in => gpr_write,
241 gpr_bypassable => gpr_bypassable,
243 update_gpr_write_valid => update_gpr_write_valid,
244 update_gpr_write_reg => update_gpr_write_reg,
246 gpr_a_read_valid_in => gpr_a_read_valid,
247 gpr_a_read_in => gpr_a_read,
249 gpr_b_read_valid_in => gpr_b_read_valid,
250 gpr_b_read_in => gpr_b_read,
252 gpr_c_read_valid_in => gpr_c_read_valid,
253 gpr_c_read_in => gpr_c_read,
255 cr_read_in => d_in.decode.input_cr,
256 cr_write_in => cr_write_valid,
257 cr_bypass => cr_bypass,
258 cr_bypassable => cr_bypass_avail,
260 valid_out => control_valid_out,
261 stall_out => stall_out,
262 stopped_out => stopped_out,
264 gpr_bypass_a => gpr_a_bypass,
265 gpr_bypass_b => gpr_b_bypass,
266 gpr_bypass_c => gpr_c_bypass
269 deferred <= r.e.valid and busy_in;
271 decode2_0: process(clk)
273 if rising_edge(clk) then
274 if rst = '1' or flush_in = '1' or deferred = '0' then
275 if rin.e.valid = '1' then
276 report "execute " & to_hstring(rin.e.nia);
283 r_out.read1_reg <= d_in.ispr1 when d_in.decode.input_reg_a = SPR
284 else gpr_to_gspr(insn_ra(d_in.insn));
285 r_out.read2_reg <= d_in.ispr2 when d_in.decode.input_reg_b = SPR
286 else gpr_to_gspr(insn_rb(d_in.insn));
287 r_out.read3_reg <= insn_rcreg(d_in.insn) when d_in.decode.input_reg_c = RCR
288 else insn_rs(d_in.insn);
290 c_out.read <= d_in.decode.input_cr;
292 decode2_1: process(all)
293 variable v : reg_type;
294 variable mul_a : std_ulogic_vector(63 downto 0);
295 variable mul_b : std_ulogic_vector(63 downto 0);
296 variable decoded_reg_a : decode_input_reg_t;
297 variable decoded_reg_b : decode_input_reg_t;
298 variable decoded_reg_c : decode_input_reg_t;
299 variable decoded_reg_o : decode_output_reg_t;
300 variable length : std_ulogic_vector(3 downto 0);
304 v.e := Decode2ToExecute1Init;
306 mul_a := (others => '0');
307 mul_b := (others => '0');
309 --v.e.input_cr := d_in.decode.input_cr;
310 --v.e.output_cr := d_in.decode.output_cr;
312 decoded_reg_a := decode_input_reg_a (d_in.decode.input_reg_a, d_in.insn, r_in.read1_data, d_in.ispr1,
314 decoded_reg_b := decode_input_reg_b (d_in.decode.input_reg_b, d_in.insn, r_in.read2_data, d_in.ispr2);
315 decoded_reg_c := decode_input_reg_c (d_in.decode.input_reg_c, d_in.insn, r_in.read3_data);
316 decoded_reg_o := decode_output_reg (d_in.decode.output_reg_a, d_in.insn, d_in.ispr1);
318 r_out.read1_enable <= decoded_reg_a.reg_valid and d_in.valid;
319 r_out.read2_enable <= decoded_reg_b.reg_valid and d_in.valid;
320 r_out.read3_enable <= decoded_reg_c.reg_valid and d_in.valid;
322 case d_in.decode.length is
337 v.e.unit := d_in.decode.unit;
338 v.e.insn_type := d_in.decode.insn_type;
339 v.e.read_reg1 := decoded_reg_a.reg;
340 v.e.read_data1 := decoded_reg_a.data;
341 v.e.bypass_data1 := gpr_a_bypass;
342 v.e.read_reg2 := decoded_reg_b.reg;
343 v.e.read_data2 := decoded_reg_b.data;
344 v.e.bypass_data2 := gpr_b_bypass;
345 v.e.read_data3 := decoded_reg_c.data;
346 v.e.bypass_data3 := gpr_c_bypass;
347 v.e.write_reg := decoded_reg_o.reg;
348 v.e.rc := decode_rc(d_in.decode.rc, d_in.insn);
349 if not (d_in.decode.insn_type = OP_MUL_H32 or d_in.decode.insn_type = OP_MUL_H64) then
350 v.e.oe := decode_oe(d_in.decode.rc, d_in.insn);
352 v.e.cr := c_in.read_cr_data;
353 v.e.bypass_cr := cr_bypass;
354 v.e.xerc := c_in.read_xerc_data;
355 v.e.invert_a := d_in.decode.invert_a;
356 v.e.invert_out := d_in.decode.invert_out;
357 v.e.input_carry := d_in.decode.input_carry;
358 v.e.output_carry := d_in.decode.output_carry;
359 v.e.is_32bit := d_in.decode.is_32bit;
360 v.e.is_signed := d_in.decode.is_signed;
361 if d_in.decode.lr = '1' then
362 v.e.lr := insn_lk(d_in.insn);
364 v.e.insn := d_in.insn;
365 v.e.data_len := length;
366 v.e.byte_reverse := d_in.decode.byte_reverse;
367 v.e.sign_extend := d_in.decode.sign_extend;
368 v.e.update := d_in.decode.update;
369 v.e.reserve := d_in.decode.reserve;
370 v.e.br_pred := d_in.br_pred;
373 control_valid_in <= d_in.valid;
374 control_sgl_pipe <= d_in.decode.sgl_pipe;
376 gpr_write_valid <= decoded_reg_o.reg_valid;
377 gpr_write <= decoded_reg_o.reg;
378 gpr_bypassable <= '0';
379 if EX1_BYPASS and d_in.decode.unit = ALU then
380 gpr_bypassable <= '1';
382 update_gpr_write_valid <= d_in.decode.update;
383 update_gpr_write_reg <= decoded_reg_a.reg;
385 -- there are no instructions that have both update=1 and lr=1
386 update_gpr_write_valid <= '1';
387 update_gpr_write_reg <= fast_spr_num(SPR_LR);
390 gpr_a_read_valid <= decoded_reg_a.reg_valid;
391 gpr_a_read <= decoded_reg_a.reg;
393 gpr_b_read_valid <= decoded_reg_b.reg_valid;
394 gpr_b_read <= decoded_reg_b.reg;
396 gpr_c_read_valid <= decoded_reg_c.reg_valid;
397 gpr_c_read <= gspr_to_gpr(decoded_reg_c.reg);
399 cr_write_valid <= d_in.decode.output_cr or decode_rc(d_in.decode.rc, d_in.insn);
400 cr_bypass_avail <= '0';
402 cr_bypass_avail <= d_in.decode.output_cr;
405 v.e.valid := control_valid_out;
406 if d_in.decode.unit = NONE then
407 v.e.insn_type := OP_ILLEGAL;
410 if rst = '1' or flush_in = '1' then
411 v.e := Decode2ToExecute1Init;
421 d2_log: if LOG_LENGTH > 0 generate
422 signal log_data : std_ulogic_vector(9 downto 0);
424 dec2_log : process(clk)
426 if rising_edge(clk) then
427 log_data <= r.e.nia(5 downto 2) &
439 end architecture behaviour;