You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
microwatt/common.vhdl

683 lines
26 KiB
VHDL

library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
library work;
use work.utils.all;
use work.decode_types.all;
package common is
-- Processor Version Number
constant PVR_MICROWATT : std_ulogic_vector(31 downto 0) := x"00630000";
-- MSR bit numbers
constant MSR_SF : integer := (63 - 0); -- Sixty-Four bit mode
constant MSR_EE : integer := (63 - 48); -- External interrupt Enable
constant MSR_PR : integer := (63 - 49); -- PRoblem state
constant MSR_FP : integer := (63 - 50); -- Floating Point available
constant MSR_FE0 : integer := (63 - 52); -- Floating Exception mode
constant MSR_SE : integer := (63 - 53); -- Single-step bit of TE field
constant MSR_BE : integer := (63 - 54); -- Branch trace bit of TE field
constant MSR_FE1 : integer := (63 - 55); -- Floating Exception mode
constant MSR_IR : integer := (63 - 58); -- Instruction Relocation
constant MSR_DR : integer := (63 - 59); -- Data Relocation
constant MSR_RI : integer := (63 - 62); -- Recoverable Interrupt
constant MSR_LE : integer := (63 - 63); -- Little Endian
-- SPR numbers
subtype spr_num_t is integer range 0 to 1023;
function decode_spr_num(insn: std_ulogic_vector(31 downto 0)) return spr_num_t;
constant SPR_XER : spr_num_t := 1;
constant SPR_LR : spr_num_t := 8;
constant SPR_CTR : spr_num_t := 9;
constant SPR_TAR : spr_num_t := 815;
constant SPR_DSISR : spr_num_t := 18;
constant SPR_DAR : spr_num_t := 19;
constant SPR_TB : spr_num_t := 268;
constant SPR_TBU : spr_num_t := 269;
constant SPR_DEC : spr_num_t := 22;
constant SPR_SRR0 : spr_num_t := 26;
constant SPR_SRR1 : spr_num_t := 27;
constant SPR_CFAR : spr_num_t := 28;
constant SPR_HSRR0 : spr_num_t := 314;
constant SPR_HSRR1 : spr_num_t := 315;
constant SPR_SPRG0 : spr_num_t := 272;
constant SPR_SPRG1 : spr_num_t := 273;
constant SPR_SPRG2 : spr_num_t := 274;
constant SPR_SPRG3 : spr_num_t := 275;
constant SPR_SPRG3U : spr_num_t := 259;
constant SPR_HSPRG0 : spr_num_t := 304;
constant SPR_HSPRG1 : spr_num_t := 305;
constant SPR_PID : spr_num_t := 48;
constant SPR_PTCR : spr_num_t := 464;
constant SPR_PVR : spr_num_t := 287;
-- GPR indices in the register file (GPR only)
subtype gpr_index_t is std_ulogic_vector(4 downto 0);
-- Extended GPR index (can hold an SPR or a FPR)
subtype gspr_index_t is std_ulogic_vector(6 downto 0);
-- FPR indices
subtype fpr_index_t is std_ulogic_vector(4 downto 0);
-- Some SPRs are stored in the register file, they use the magic
-- GPR numbers above 31.
--
-- The function fast_spr_num() returns the corresponding fast
-- pseudo-GPR number for a given SPR number. The result MSB
-- indicates if this is indeed a fast SPR. If clear, then
-- the SPR is not stored in the GPR file.
--
-- FPRs are also stored in the register file, using GSPR
-- numbers from 64 to 95.
--
function fast_spr_num(spr: spr_num_t) return gspr_index_t;
-- Indices conversion functions
function gspr_to_gpr(i: gspr_index_t) return gpr_index_t;
function gpr_to_gspr(i: gpr_index_t) return gspr_index_t;
function gpr_or_spr_to_gspr(g: gpr_index_t; s: gspr_index_t) return gspr_index_t;
function is_fast_spr(s: gspr_index_t) return std_ulogic;
function fpr_to_gspr(f: fpr_index_t) return gspr_index_t;
-- The XER is split: the common bits (CA, OV, SO, OV32 and CA32) are
-- in the CR file as a kind of CR extension (with a separate write
-- control). The rest is stored as a fast SPR.
type xer_common_t is record
ca : std_ulogic;
ca32 : std_ulogic;
ov : std_ulogic;
ov32 : std_ulogic;
so : std_ulogic;
end record;
constant xerc_init : xer_common_t := (others => '0');
-- FPSCR bit numbers
constant FPSCR_FX : integer := 63 - 32;
constant FPSCR_FEX : integer := 63 - 33;
constant FPSCR_VX : integer := 63 - 34;
constant FPSCR_OX : integer := 63 - 35;
constant FPSCR_UX : integer := 63 - 36;
constant FPSCR_ZX : integer := 63 - 37;
constant FPSCR_XX : integer := 63 - 38;
constant FPSCR_VXSNAN : integer := 63 - 39;
constant FPSCR_VXISI : integer := 63 - 40;
constant FPSCR_VXIDI : integer := 63 - 41;
constant FPSCR_VXZDZ : integer := 63 - 42;
constant FPSCR_VXIMZ : integer := 63 - 43;
constant FPSCR_VXVC : integer := 63 - 44;
constant FPSCR_FR : integer := 63 - 45;
constant FPSCR_FI : integer := 63 - 46;
constant FPSCR_C : integer := 63 - 47;
constant FPSCR_FL : integer := 63 - 48;
constant FPSCR_FG : integer := 63 - 49;
constant FPSCR_FE : integer := 63 - 50;
constant FPSCR_FU : integer := 63 - 51;
constant FPSCR_VXSOFT : integer := 63 - 53;
constant FPSCR_VXSQRT : integer := 63 - 54;
constant FPSCR_VXCVI : integer := 63 - 55;
constant FPSCR_VE : integer := 63 - 56;
constant FPSCR_OE : integer := 63 - 57;
constant FPSCR_UE : integer := 63 - 58;
constant FPSCR_ZE : integer := 63 - 59;
constant FPSCR_XE : integer := 63 - 60;
constant FPSCR_NI : integer := 63 - 61;
constant FPSCR_RN : integer := 63 - 63;
-- Used for tracking instruction completion and pending register writes
constant TAG_COUNT : positive := 4;
constant TAG_NUMBER_BITS : natural := log2(TAG_COUNT);
subtype tag_number_t is integer range 0 to TAG_COUNT - 1;
subtype tag_index_t is unsigned(TAG_NUMBER_BITS - 1 downto 0);
type instr_tag_t is record
tag : tag_number_t;
valid : std_ulogic;
end record;
constant instr_tag_init : instr_tag_t := (tag => 0, valid => '0');
function tag_match(tag1 : instr_tag_t; tag2 : instr_tag_t) return boolean;
subtype intr_vector_t is integer range 0 to 16#fff#;
-- For now, fixed 16 sources, make this either a parametric
-- package of some sort or an unconstrainted array.
type ics_to_icp_t is record
-- Level interrupts only, ICS just keeps prsenting the
-- highest priority interrupt. Once handling edge, something
-- smarter involving handshake & reject support will be needed
src : std_ulogic_vector(3 downto 0);
pri : std_ulogic_vector(7 downto 0);
end record;
-- This needs to die...
type ctrl_t is record
tb: std_ulogic_vector(63 downto 0);
dec: std_ulogic_vector(63 downto 0);
msr: std_ulogic_vector(63 downto 0);
cfar: std_ulogic_vector(63 downto 0);
end record;
type Fetch1ToIcacheType is record
req: std_ulogic;
virt_mode : std_ulogic;
priv_mode : std_ulogic;
big_endian : std_ulogic;
stop_mark: std_ulogic;
sequential: std_ulogic;
predicted : std_ulogic;
nia: std_ulogic_vector(63 downto 0);
end record;
type IcacheToDecode1Type is record
valid: std_ulogic;
stop_mark: std_ulogic;
fetch_failed: std_ulogic;
nia: std_ulogic_vector(63 downto 0);
insn: std_ulogic_vector(31 downto 0);
big_endian: std_ulogic;
next_predicted: std_ulogic;
end record;
type Decode1ToDecode2Type is record
valid: std_ulogic;
stop_mark : std_ulogic;
nia: std_ulogic_vector(63 downto 0);
insn: std_ulogic_vector(31 downto 0);
ispr1: gspr_index_t; -- (G)SPR used for branch condition (CTR) or mfspr
ispr2: gspr_index_t; -- (G)SPR used for branch target (CTR, LR, TAR)
ispro: gspr_index_t; -- (G)SPR written with LR or CTR
decode: decode_rom_t;
br_pred: std_ulogic; -- Branch was predicted to be taken
big_endian: std_ulogic;
end record;
constant Decode1ToDecode2Init : Decode1ToDecode2Type :=
(valid => '0', stop_mark => '0', nia => (others => '0'), insn => (others => '0'),
ispr1 => (others => '0'), ispr2 => (others => '0'), ispro => (others => '0'),
decode => decode_rom_init, br_pred => '0', big_endian => '0');
type Decode1ToFetch1Type is record
redirect : std_ulogic;
redirect_nia : std_ulogic_vector(63 downto 0);
end record;
type bypass_data_t is record
tag : instr_tag_t;
data : std_ulogic_vector(63 downto 0);
end record;
constant bypass_data_init : bypass_data_t := (tag => instr_tag_init, data => (others => '0'));
type cr_bypass_data_t is record
tag : instr_tag_t;
data : std_ulogic_vector(31 downto 0);
end record;
constant cr_bypass_data_init : cr_bypass_data_t := (tag => instr_tag_init, data => (others => '0'));
type Decode2ToExecute1Type is record
valid: std_ulogic;
unit : unit_t;
fac : facility_t;
insn_type: insn_type_t;
nia: std_ulogic_vector(63 downto 0);
instr_tag : instr_tag_t;
write_reg: gspr_index_t;
write_reg_enable: std_ulogic;
read_reg1: gspr_index_t;
read_reg2: gspr_index_t;
read_data1: std_ulogic_vector(63 downto 0);
read_data2: std_ulogic_vector(63 downto 0);
read_data3: std_ulogic_vector(63 downto 0);
cr: std_ulogic_vector(31 downto 0);
xerc: xer_common_t;
lr: std_ulogic;
br_abs: std_ulogic;
rc: std_ulogic;
oe: std_ulogic;
invert_a: std_ulogic;
addm1 : std_ulogic;
invert_out: std_ulogic;
input_carry: carry_in_t;
output_carry: std_ulogic;
input_cr: std_ulogic;
output_cr: std_ulogic;
output_xer: std_ulogic;
is_32bit: std_ulogic;
is_signed: std_ulogic;
insn: std_ulogic_vector(31 downto 0);
data_len: std_ulogic_vector(3 downto 0);
byte_reverse : std_ulogic;
sign_extend : std_ulogic; -- do we need to sign extend?
update : std_ulogic; -- is this an update instruction?
reserve : std_ulogic; -- set for larx/stcx
br_pred : std_ulogic;
result_sel : std_ulogic_vector(2 downto 0); -- select source of result
sub_select : std_ulogic_vector(2 downto 0); -- sub-result selection
repeat : std_ulogic; -- set if instruction is cracked into two ops
second : std_ulogic; -- set if this is the second op
end record;
constant Decode2ToExecute1Init : Decode2ToExecute1Type :=
(valid => '0', unit => NONE, fac => NONE, insn_type => OP_ILLEGAL, instr_tag => instr_tag_init,
write_reg_enable => '0',
lr => '0', br_abs => '0', rc => '0', oe => '0', invert_a => '0', addm1 => '0',
invert_out => '0', input_carry => ZERO, output_carry => '0', input_cr => '0',
output_cr => '0', output_xer => '0',
is_32bit => '0', is_signed => '0', xerc => xerc_init, reserve => '0', br_pred => '0',
byte_reverse => '0', sign_extend => '0', update => '0', nia => (others => '0'),
read_data1 => (others => '0'), read_data2 => (others => '0'), read_data3 => (others => '0'),
cr => (others => '0'), insn => (others => '0'), data_len => (others => '0'),
result_sel => "000", sub_select => "000",
repeat => '0', second => '0', others => (others => '0'));
type MultiplyInputType is record
valid: std_ulogic;
data1: std_ulogic_vector(63 downto 0);
data2: std_ulogic_vector(63 downto 0);
addend: std_ulogic_vector(127 downto 0);
is_32bit: std_ulogic;
not_result: std_ulogic;
end record;
constant MultiplyInputInit : MultiplyInputType := (valid => '0',
is_32bit => '0', not_result => '0',
others => (others => '0'));
type MultiplyOutputType is record
valid: std_ulogic;
result: std_ulogic_vector(127 downto 0);
overflow : std_ulogic;
end record;
constant MultiplyOutputInit : MultiplyOutputType := (valid => '0', overflow => '0',
others => (others => '0'));
type Execute1ToDividerType is record
valid: std_ulogic;
dividend: std_ulogic_vector(63 downto 0);
divisor: std_ulogic_vector(63 downto 0);
is_signed: std_ulogic;
is_32bit: std_ulogic;
is_extended: std_ulogic;
is_modulus: std_ulogic;
neg_result: std_ulogic;
end record;
constant Execute1ToDividerInit: Execute1ToDividerType := (valid => '0', is_signed => '0', is_32bit => '0',
is_extended => '0', is_modulus => '0',
neg_result => '0', others => (others => '0'));
type Decode2ToRegisterFileType is record
read1_enable : std_ulogic;
read1_reg : gspr_index_t;
read2_enable : std_ulogic;
read2_reg : gspr_index_t;
read3_enable : std_ulogic;
read3_reg : gspr_index_t;
end record;
type RegisterFileToDecode2Type is record
read1_data : std_ulogic_vector(63 downto 0);
read2_data : std_ulogic_vector(63 downto 0);
read3_data : std_ulogic_vector(63 downto 0);
end record;
type Decode2ToCrFileType is record
read : std_ulogic;
end record;
type CrFileToDecode2Type is record
read_cr_data : std_ulogic_vector(31 downto 0);
read_xerc_data : xer_common_t;
end record;
type Execute1ToLoadstore1Type is record
valid : std_ulogic;
op : insn_type_t; -- what ld/st or m[tf]spr or TLB op to do
nia : std_ulogic_vector(63 downto 0);
insn : std_ulogic_vector(31 downto 0);
instr_tag : instr_tag_t;
addr1 : std_ulogic_vector(63 downto 0);
addr2 : std_ulogic_vector(63 downto 0);
data : std_ulogic_vector(63 downto 0); -- data to write, unused for read
write_reg : gspr_index_t;
length : std_ulogic_vector(3 downto 0);
ci : std_ulogic; -- cache-inhibited load/store
byte_reverse : std_ulogic;
sign_extend : std_ulogic; -- do we need to sign extend?
update : std_ulogic; -- is this an update instruction?
xerc : xer_common_t;
reserve : std_ulogic; -- set for larx/stcx.
rc : std_ulogic; -- set for stcx.
virt_mode : std_ulogic; -- do translation through TLB
priv_mode : std_ulogic; -- privileged mode (MSR[PR] = 0)
mode_32bit : std_ulogic; -- trim addresses to 32 bits
is_32bit : std_ulogic;
repeat : std_ulogic;
second : std_ulogic;
msr : std_ulogic_vector(63 downto 0);
end record;
constant Execute1ToLoadstore1Init : Execute1ToLoadstore1Type :=
(valid => '0', op => OP_ILLEGAL, ci => '0', byte_reverse => '0',
sign_extend => '0', update => '0', xerc => xerc_init,
reserve => '0', rc => '0', virt_mode => '0', priv_mode => '0',
nia => (others => '0'), insn => (others => '0'),
instr_tag => instr_tag_init,
addr1 => (others => '0'), addr2 => (others => '0'), data => (others => '0'),
write_reg => (others => '0'),
length => (others => '0'),
mode_32bit => '0', is_32bit => '0',
repeat => '0', second => '0',
msr => (others => '0'));
type Loadstore1ToExecute1Type is record
busy : std_ulogic;
in_progress : std_ulogic;
interrupt : std_ulogic;
end record;
type Loadstore1ToDcacheType is record
valid : std_ulogic;
hold : std_ulogic;
load : std_ulogic; -- is this a load
dcbz : std_ulogic;
nc : std_ulogic;
reserve : std_ulogic;
atomic : std_ulogic; -- part of a multi-transfer atomic op
atomic_last : std_ulogic;
virt_mode : std_ulogic;
priv_mode : std_ulogic;
addr : std_ulogic_vector(63 downto 0);
data : std_ulogic_vector(63 downto 0); -- valid the cycle after .valid = 1
byte_sel : std_ulogic_vector(7 downto 0);
end record;
type DcacheToLoadstore1Type is record
valid : std_ulogic;
data : std_ulogic_vector(63 downto 0);
store_done : std_ulogic;
error : std_ulogic;
cache_paradox : std_ulogic;
end record;
type Loadstore1ToMmuType is record
valid : std_ulogic;
tlbie : std_ulogic;
slbia : std_ulogic;
mtspr : std_ulogic;
iside : std_ulogic;
load : std_ulogic;
priv : std_ulogic;
sprn : std_ulogic_vector(9 downto 0);
addr : std_ulogic_vector(63 downto 0);
rs : std_ulogic_vector(63 downto 0);
end record;
type MmuToLoadstore1Type is record
done : std_ulogic;
err : std_ulogic;
invalid : std_ulogic;
badtree : std_ulogic;
segerr : std_ulogic;
perm_error : std_ulogic;
rc_error : std_ulogic;
sprval : std_ulogic_vector(63 downto 0);
end record;
type MmuToDcacheType is record
valid : std_ulogic;
tlbie : std_ulogic;
doall : std_ulogic;
tlbld : std_ulogic;
addr : std_ulogic_vector(63 downto 0);
pte : std_ulogic_vector(63 downto 0);
end record;
type DcacheToMmuType is record
stall : std_ulogic;
done : std_ulogic;
err : std_ulogic;
data : std_ulogic_vector(63 downto 0);
end record;
type MmuToIcacheType is record
tlbld : std_ulogic;
tlbie : std_ulogic;
doall : std_ulogic;
addr : std_ulogic_vector(63 downto 0);
pte : std_ulogic_vector(63 downto 0);
end record;
type Loadstore1ToWritebackType is record
valid : std_ulogic;
instr_tag : instr_tag_t;
write_enable: std_ulogic;
write_reg : gspr_index_t;
write_data : std_ulogic_vector(63 downto 0);
xerc : xer_common_t;
rc : std_ulogic;
store_done : std_ulogic;
interrupt : std_ulogic;
intr_vec : intr_vector_t;
srr0: std_ulogic_vector(63 downto 0);
srr1: std_ulogic_vector(15 downto 0);
end record;
constant Loadstore1ToWritebackInit : Loadstore1ToWritebackType :=
(valid => '0', instr_tag => instr_tag_init, write_enable => '0',
write_reg => (others => '0'), write_data => (others => '0'),
xerc => xerc_init, rc => '0', store_done => '0',
interrupt => '0', intr_vec => 0,
srr0 => (others => '0'), srr1 => (others => '0'));
type Execute1ToWritebackType is record
valid: std_ulogic;
instr_tag : instr_tag_t;
rc : std_ulogic;
mode_32bit : std_ulogic;
write_enable : std_ulogic;
write_reg: gspr_index_t;
write_data: std_ulogic_vector(63 downto 0);
write_cr_enable : std_ulogic;
write_cr_mask : std_ulogic_vector(7 downto 0);
write_cr_data : std_ulogic_vector(31 downto 0);
write_xerc_enable : std_ulogic;
xerc : xer_common_t;
interrupt : std_ulogic;
intr_vec : intr_vector_t;
redirect: std_ulogic;
redir_mode: std_ulogic_vector(3 downto 0);
last_nia: std_ulogic_vector(63 downto 0);
br_offset: std_ulogic_vector(63 downto 0);
br_last: std_ulogic;
br_taken: std_ulogic;
abs_br: std_ulogic;
srr1: std_ulogic_vector(15 downto 0);
msr: std_ulogic_vector(63 downto 0);
end record;
constant Execute1ToWritebackInit : Execute1ToWritebackType :=
(valid => '0', instr_tag => instr_tag_init, rc => '0', mode_32bit => '0',
write_enable => '0', write_cr_enable => '0',
write_xerc_enable => '0', xerc => xerc_init,
write_data => (others => '0'), write_cr_mask => (others => '0'),
write_cr_data => (others => '0'), write_reg => (others => '0'),
interrupt => '0', intr_vec => 0, redirect => '0', redir_mode => "0000",
last_nia => (others => '0'), br_offset => (others => '0'),
br_last => '0', br_taken => '0', abs_br => '0',
srr1 => (others => '0'), msr => (others => '0'));
type Execute1ToFPUType is record
valid : std_ulogic;
op : insn_type_t;
nia : std_ulogic_vector(63 downto 0);
itag : instr_tag_t;
insn : std_ulogic_vector(31 downto 0);
single : std_ulogic;
fe_mode : std_ulogic_vector(1 downto 0);
fra : std_ulogic_vector(63 downto 0);
frb : std_ulogic_vector(63 downto 0);
frc : std_ulogic_vector(63 downto 0);
frt : gspr_index_t;
rc : std_ulogic;
out_cr : std_ulogic;
end record;
constant Execute1ToFPUInit : Execute1ToFPUType := (valid => '0', op => OP_ILLEGAL, nia => (others => '0'),
itag => instr_tag_init,
insn => (others => '0'), fe_mode => "00", rc => '0',
fra => (others => '0'), frb => (others => '0'),
frc => (others => '0'), frt => (others => '0'),
single => '0', out_cr => '0');
type FPUToExecute1Type is record
busy : std_ulogic;
exception : std_ulogic;
end record;
constant FPUToExecute1Init : FPUToExecute1Type := (others => '0');
type FPUToWritebackType is record
valid : std_ulogic;
interrupt : std_ulogic;
instr_tag : instr_tag_t;
write_enable : std_ulogic;
write_reg : gspr_index_t;
write_data : std_ulogic_vector(63 downto 0);
write_cr_enable : std_ulogic;
write_cr_mask : std_ulogic_vector(7 downto 0);
write_cr_data : std_ulogic_vector(31 downto 0);
intr_vec : intr_vector_t;
srr0 : std_ulogic_vector(63 downto 0);
srr1 : std_ulogic_vector(15 downto 0);
end record;
constant FPUToWritebackInit : FPUToWritebackType :=
(valid => '0', interrupt => '0', instr_tag => instr_tag_init,
write_enable => '0', write_reg => (others => '0'),
write_cr_enable => '0', write_cr_mask => (others => '0'),
write_cr_data => (others => '0'),
intr_vec => 0, srr1 => (others => '0'),
others => (others => '0'));
type DividerToExecute1Type is record
valid: std_ulogic;
write_reg_data: std_ulogic_vector(63 downto 0);
overflow : std_ulogic;
end record;
constant DividerToExecute1Init : DividerToExecute1Type := (valid => '0', overflow => '0',
others => (others => '0'));
type WritebackToFetch1Type is record
redirect: std_ulogic;
virt_mode: std_ulogic;
priv_mode: std_ulogic;
big_endian: std_ulogic;
mode_32bit: std_ulogic;
redirect_nia: std_ulogic_vector(63 downto 0);
br_nia : std_ulogic_vector(63 downto 0);
br_last : std_ulogic;
br_taken : std_ulogic;
end record;
constant WritebackToFetch1Init : WritebackToFetch1Type :=
(redirect => '0', virt_mode => '0', priv_mode => '0', big_endian => '0',
mode_32bit => '0', redirect_nia => (others => '0'),
br_last => '0', br_taken => '0', br_nia => (others => '0'));
type WritebackToRegisterFileType is record
write_reg : gspr_index_t;
write_data : std_ulogic_vector(63 downto 0);
write_enable : std_ulogic;
end record;
constant WritebackToRegisterFileInit : WritebackToRegisterFileType :=
(write_enable => '0', write_data => (others => '0'), others => (others => '0'));
type WritebackToCrFileType is record
write_cr_enable : std_ulogic;
write_cr_mask : std_ulogic_vector(7 downto 0);
write_cr_data : std_ulogic_vector(31 downto 0);
write_xerc_enable : std_ulogic;
write_xerc_data : xer_common_t;
end record;
constant WritebackToCrFileInit : WritebackToCrFileType := (write_cr_enable => '0', write_xerc_enable => '0',
write_xerc_data => xerc_init,
write_cr_mask => (others => '0'),
write_cr_data => (others => '0'));
end common;
package body common is
function decode_spr_num(insn: std_ulogic_vector(31 downto 0)) return spr_num_t is
begin
return to_integer(unsigned(insn(15 downto 11) & insn(20 downto 16)));
end;
function fast_spr_num(spr: spr_num_t) return gspr_index_t is
variable n : integer range 0 to 31;
-- tmp variable introduced as workaround for VCS compilation
-- simulation was failing with subtype constraint mismatch error
-- see GitHub PR #173
variable tmp : std_ulogic_vector(4 downto 0);
begin
case spr is
when SPR_LR =>
n := 0; -- N.B. decode2 relies on this specific value
when SPR_CTR =>
n := 1; -- N.B. decode2 relies on this specific value
when SPR_SRR0 =>
n := 2;
when SPR_SRR1 =>
n := 3;
when SPR_HSRR0 =>
n := 4;
when SPR_HSRR1 =>
n := 5;
when SPR_SPRG0 =>
n := 6;
when SPR_SPRG1 =>
n := 7;
when SPR_SPRG2 =>
n := 8;
when SPR_SPRG3 | SPR_SPRG3U =>
n := 9;
when SPR_HSPRG0 =>
n := 10;
when SPR_HSPRG1 =>
n := 11;
when SPR_XER =>
n := 12;
when SPR_TAR =>
n := 13;
when others =>
n := 0;
return "0000000";
end case;
tmp := std_ulogic_vector(to_unsigned(n, 5));
return "01" & tmp;
end;
function gspr_to_gpr(i: gspr_index_t) return gpr_index_t is
begin
return i(4 downto 0);
end;
function gpr_to_gspr(i: gpr_index_t) return gspr_index_t is
begin
return "00" & i;
end;
function gpr_or_spr_to_gspr(g: gpr_index_t; s: gspr_index_t) return gspr_index_t is
begin
if s(5) = '1' then
return s;
else
return gpr_to_gspr(g);
end if;
end;
function is_fast_spr(s: gspr_index_t) return std_ulogic is
begin
return s(5);
end;
function fpr_to_gspr(f: fpr_index_t) return gspr_index_t is
begin
return "10" & f;
end;
function tag_match(tag1 : instr_tag_t; tag2 : instr_tag_t) return boolean is
begin
return tag1.valid = '1' and tag2.valid = '1' and tag1.tag = tag2.tag;
end;
end common;