Merge branch 'mmu'

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
pull/169/head
Paul Mackerras 4 years ago
commit c164a2f4ea

@ -31,7 +31,7 @@ common.o: decode_types.o
control.o: gpr_hazard.o cr_hazard.o common.o
sim_jtag.o: sim_jtag_socket.o
core_tb.o: common.o wishbone_types.o core.o soc.o sim_jtag.o
core.o: common.o wishbone_types.o fetch1.o fetch2.o icache.o decode1.o decode2.o register_file.o cr_file.o execute1.o loadstore1.o dcache.o writeback.o core_debug.o
core.o: common.o wishbone_types.o fetch1.o fetch2.o icache.o decode1.o decode2.o register_file.o cr_file.o execute1.o loadstore1.o mmu.o dcache.o writeback.o core_debug.o
core_debug.o: common.o
countzero.o:
countzero_tb.o: common.o glibc_random.o countzero.o
@ -58,10 +58,11 @@ icache_tb.o: common.o wishbone_types.o icache.o wishbone_bram_wrapper.o
dcache.o: utils.o common.o wishbone_types.o plru.o cache_ram.o utils.o
dcache_tb.o: common.o wishbone_types.o dcache.o wishbone_bram_wrapper.o
insn_helpers.o:
loadstore1.o: common.o helpers.o decode_types.o
loadstore1.o: common.o decode_types.o
logical.o: decode_types.o
multiply_tb.o: decode_types.o common.o glibc_random.o ppc_fx_insns.o multiply.o
multiply.o: common.o decode_types.o
mmu.o: common.o
divider_tb.o: decode_types.o common.o glibc_random.o ppc_fx_insns.o divider.o
divider.o: common.o decode_types.o
ppc_fx_insns.o: helpers.o

@ -24,6 +24,8 @@ package common is
constant SPR_XER : spr_num_t := 1;
constant SPR_LR : spr_num_t := 8;
constant SPR_CTR : spr_num_t := 9;
constant SPR_DSISR : spr_num_t := 18;
constant SPR_DAR : spr_num_t := 19;
constant SPR_TB : spr_num_t := 268;
constant SPR_DEC : spr_num_t := 22;
constant SPR_SRR0 : spr_num_t := 26;
@ -37,6 +39,8 @@ package common is
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_PRTBL : spr_num_t := 720;

-- GPR indices in the register file (GPR only)
subtype gpr_index_t is std_ulogic_vector(4 downto 0);
@ -86,6 +90,8 @@ package common is

type Fetch1ToIcacheType is record
req: std_ulogic;
virt_mode : std_ulogic;
priv_mode : std_ulogic;
stop_mark: std_ulogic;
nia: std_ulogic_vector(63 downto 0);
end record;
@ -93,6 +99,7 @@ package common is
type IcacheToFetch2Type 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);
end record;
@ -100,10 +107,12 @@ package common is
type Fetch2ToDecode1Type 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);
end record;
constant Fetch2ToDecode1Init : Fetch2ToDecode1Type := (valid => '0', stop_mark => '0', others => (others => '0'));
constant Fetch2ToDecode1Init : Fetch2ToDecode1Type := (valid => '0', stop_mark => '0', fetch_failed => '0',
others => (others => '0'));

type Decode1ToDecode2Type is record
valid: std_ulogic;
@ -208,13 +217,18 @@ package common is

type Execute1ToFetch1Type is record
redirect: std_ulogic;
virt_mode: std_ulogic;
priv_mode: std_ulogic;
redirect_nia: std_ulogic_vector(63 downto 0);
end record;
constant Execute1ToFetch1TypeInit : Execute1ToFetch1Type := (redirect => '0', others => (others => '0'));
constant Execute1ToFetch1TypeInit : Execute1ToFetch1Type := (redirect => '0', virt_mode => '0',
priv_mode => '0', others => (others => '0'));

type Execute1ToLoadstore1Type is record
valid : std_ulogic;
op : insn_type_t; -- what ld/st op to do
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);
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
@ -228,17 +242,32 @@ package common is
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)
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', others => (others => '0'));
reserve => '0', rc => '0', virt_mode => '0', priv_mode => '0',
others => (others => '0'));

type Loadstore1ToExecute1Type is record
exception : std_ulogic;
invalid : std_ulogic;
perm_error : std_ulogic;
rc_error : std_ulogic;
badtree : std_ulogic;
segment_fault : std_ulogic;
instr_fault : std_ulogic;
end record;

type Loadstore1ToDcacheType is record
valid : std_ulogic;
load : std_ulogic;
load : std_ulogic; -- is this a load
dcbz : std_ulogic;
nc : std_ulogic;
reserve : std_ulogic;
virt_mode : std_ulogic;
priv_mode : std_ulogic;
addr : std_ulogic_vector(63 downto 0);
data : std_ulogic_vector(63 downto 0);
byte_sel : std_ulogic_vector(7 downto 0);
@ -249,6 +278,54 @@ package common is
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;
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

@ -47,6 +47,7 @@ architecture behave of core is
-- icache signals
signal fetch1_to_icache : Fetch1ToIcacheType;
signal icache_to_fetch2 : IcacheToFetch2Type;
signal mmu_to_icache : MmuToIcacheType;

-- decode signals
signal decode1_to_decode2: Decode1ToDecode2Type;
@ -68,11 +69,16 @@ architecture behave of core is

-- load store signals
signal execute1_to_loadstore1: Execute1ToLoadstore1Type;
signal loadstore1_to_execute1: Loadstore1ToExecute1Type;
signal loadstore1_to_writeback: Loadstore1ToWritebackType;
signal loadstore1_to_mmu: Loadstore1ToMmuType;
signal mmu_to_loadstore1: MmuToLoadstore1Type;

-- dcache signals
signal loadstore1_to_dcache: Loadstore1ToDcacheType;
signal dcache_to_loadstore1: DcacheToLoadstore1Type;
signal mmu_to_dcache: MmuToDcacheType;
signal dcache_to_mmu: DcacheToMmuType;

-- local signals
signal fetch1_stall_in : std_ulogic;
@ -100,6 +106,13 @@ architecture behave of core is
signal dbg_core_rst: std_ulogic;
signal dbg_icache_rst: std_ulogic;

signal dbg_gpr_req : std_ulogic;
signal dbg_gpr_ack : std_ulogic;
signal dbg_gpr_addr : gspr_index_t;
signal dbg_gpr_data : std_ulogic_vector(63 downto 0);

signal msr : std_ulogic_vector(63 downto 0);

-- Debug status
signal dbg_core_is_stopped: std_ulogic;

@ -121,6 +134,7 @@ architecture behave of core is
attribute keep_hierarchy of cr_file_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of execute1_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of loadstore1_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of mmu_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of dcache_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of writeback_0 : label is keep_h(DISABLE_FLATTEN);
attribute keep_hierarchy of debug_0 : label is keep_h(DISABLE_FLATTEN);
@ -158,6 +172,7 @@ begin
rst => icache_rst,
i_in => fetch1_to_icache,
i_out => icache_to_fetch2,
m_in => mmu_to_icache,
flush_in => flush,
stall_out => icache_stall_out,
wishbone_out => wishbone_insn_out,
@ -220,6 +235,10 @@ begin
d_in => decode2_to_register_file,
d_out => register_file_to_decode2,
w_in => writeback_to_register_file,
dbg_gpr_req => dbg_gpr_req,
dbg_gpr_ack => dbg_gpr_ack,
dbg_gpr_addr => dbg_gpr_addr,
dbg_gpr_data => dbg_gpr_data,
sim_dump => terminate,
sim_dump_done => sim_cr_dump
);
@ -247,10 +266,12 @@ begin
stall_out => ex1_stall_out,
e_in => decode2_to_execute1,
i_in => xics_in,
l_in => loadstore1_to_execute1,
l_out => execute1_to_loadstore1,
f_out => execute1_to_fetch1,
e_out => execute1_to_writeback,
icache_inval => ex1_icache_inval,
dbg_msr_out => msr,
terminate_out => terminate
);

@ -259,13 +280,27 @@ begin
clk => clk,
rst => core_rst,
l_in => execute1_to_loadstore1,
e_out => loadstore1_to_execute1,
l_out => loadstore1_to_writeback,
d_out => loadstore1_to_dcache,
d_in => dcache_to_loadstore1,
m_out => loadstore1_to_mmu,
m_in => mmu_to_loadstore1,
dc_stall => dcache_stall_out,
stall_out => ls1_stall_out
);

mmu_0: entity work.mmu
port map (
clk => clk,
rst => core_rst,
l_in => loadstore1_to_mmu,
l_out => mmu_to_loadstore1,
d_out => mmu_to_dcache,
d_in => dcache_to_mmu,
i_out => mmu_to_icache
);

dcache_0: entity work.dcache
generic map(
LINE_SIZE => 64,
@ -277,6 +312,8 @@ begin
rst => core_rst,
d_in => loadstore1_to_dcache,
d_out => dcache_to_loadstore1,
m_in => mmu_to_dcache,
m_out => dcache_to_mmu,
stall_out => dcache_stall_out,
wishbone_in => wishbone_data_in,
wishbone_out => wishbone_data_out
@ -308,6 +345,11 @@ begin
terminate => terminate,
core_stopped => dbg_core_is_stopped,
nia => fetch1_to_icache.nia,
msr => msr,
dbg_gpr_req => dbg_gpr_req,
dbg_gpr_ack => dbg_gpr_ack,
dbg_gpr_addr => dbg_gpr_addr,
dbg_gpr_data => dbg_gpr_data,
terminated_out => terminated_out
);


@ -26,6 +26,13 @@ entity core_debug is
terminate : in std_ulogic;
core_stopped : in std_ulogic;
nia : in std_ulogic_vector(63 downto 0);
msr : in std_ulogic_vector(63 downto 0);

-- GSPR register read port
dbg_gpr_req : out std_ulogic;
dbg_gpr_ack : in std_ulogic;
dbg_gpr_addr : out gspr_index_t;
dbg_gpr_data : in std_ulogic_vector(63 downto 0);

-- Misc
terminated_out : out std_ulogic
@ -61,6 +68,15 @@ architecture behave of core_debug is
-- NIA register (read only for now)
constant DBG_CORE_NIA : std_ulogic_vector(3 downto 0) := "0010";

-- MSR (read only)
constant DBG_CORE_MSR : std_ulogic_vector(3 downto 0) := "0011";

-- GSPR register index
constant DBG_CORE_GSPR_INDEX : std_ulogic_vector(3 downto 0) := "0100";

-- GSPR register data
constant DBG_CORE_GSPR_DATA : std_ulogic_vector(3 downto 0) := "0101";

-- Some internal wires
signal stat_reg : std_ulogic_vector(63 downto 0);

@ -70,10 +86,15 @@ architecture behave of core_debug is
signal do_reset : std_ulogic;
signal do_icreset : std_ulogic;
signal terminated : std_ulogic;
signal do_gspr_rd : std_ulogic;
signal gspr_index : gspr_index_t;

begin
-- Single cycle register accesses on DMI
dmi_ack <= dmi_req;
-- Single cycle register accesses on DMI except for GSPR data
dmi_ack <= dmi_req when dmi_addr /= DBG_CORE_GSPR_DATA
else dbg_gpr_ack;
dbg_gpr_req <= dmi_req when dmi_addr = DBG_CORE_GSPR_DATA
else '0';

-- Status register read composition
stat_reg <= (2 => terminated,
@ -85,6 +106,8 @@ begin
with dmi_addr select dmi_dout <=
stat_reg when DBG_CORE_STAT,
nia when DBG_CORE_NIA,
msr when DBG_CORE_MSR,
dbg_gpr_data when DBG_CORE_GSPR_DATA,
(others => '0') when others;

-- DMI writes
@ -126,6 +149,8 @@ begin
stopping <= '0';
terminated <= '0';
end if;
elsif dmi_addr = DBG_CORE_GSPR_INDEX then
gspr_index <= dmi_din(gspr_index_t'left downto 0);
end if;
else
report("DMI read from " & to_string(dmi_addr));
@ -143,6 +168,8 @@ begin
end if;
end process;

dbg_gpr_addr <= gspr_index;

-- Core control signals generated by the debug module
core_stop <= stopping and not do_step;
core_rst <= do_reset;

@ -25,7 +25,13 @@ entity dcache is
-- Number of lines in a set
NUM_LINES : positive := 32;
-- Number of ways
NUM_WAYS : positive := 4
NUM_WAYS : positive := 4;
-- L1 DTLB entries per set
TLB_SET_SIZE : positive := 64;
-- L1 DTLB number of sets
TLB_NUM_WAYS : positive := 2;
-- L1 DTLB log_2(page_size)
TLB_LG_PGSZ : positive := 12
);
port (
clk : in std_ulogic;
@ -34,6 +40,9 @@ entity dcache is
d_in : in Loadstore1ToDcacheType;
d_out : out DcacheToLoadstore1Type;

m_in : in MmuToDcacheType;
m_out : out DcacheToMmuType;

stall_out : out std_ulogic;

wishbone_out : out wishbone_master_out;
@ -56,6 +65,8 @@ architecture rtl of dcache is

-- Bit fields counts in the address

-- REAL_ADDR_BITS is the number of real address bits that we store
constant REAL_ADDR_BITS : positive := 56;
-- ROW_BITS is the number of bits to select a row
constant ROW_BITS : natural := log2(BRAM_ROWS);
-- ROW_LINEBITS is the number of bits to select a row within a line
@ -66,8 +77,10 @@ architecture rtl of dcache is
constant ROW_OFF_BITS : natural := log2(ROW_SIZE);
-- INDEX_BITS is the number if bits to select a cache line
constant INDEX_BITS : natural := log2(NUM_LINES);
-- SET_SIZE_BITS is the log base 2 of the set size
constant SET_SIZE_BITS : natural := LINE_OFF_BITS + INDEX_BITS;
-- TAG_BITS is the number of bits of the tag part of the address
constant TAG_BITS : natural := 64 - LINE_OFF_BITS - INDEX_BITS;
constant TAG_BITS : natural := REAL_ADDR_BITS - SET_SIZE_BITS;
-- WAY_BITS is the number of bits to select a way
constant WAY_BITS : natural := log2(NUM_WAYS);

@ -80,7 +93,7 @@ architecture rtl of dcache is
-- .. | |- --| ROW_OFF_BITS (3)
-- .. |----- ---| | ROW_BITS (8)
-- .. |-----| | INDEX_BITS (5)
-- .. --------| | TAG_BITS (53)
-- .. --------| | TAG_BITS (45)

subtype row_t is integer range 0 to BRAM_ROWS-1;
subtype index_t is integer range 0 to NUM_LINES-1;
@ -110,7 +123,55 @@ architecture rtl of dcache is
attribute ram_style : string;
attribute ram_style of cache_tags : signal is "distributed";

signal r0 : Loadstore1ToDcacheType;
-- L1 TLB.
constant TLB_SET_BITS : natural := log2(TLB_SET_SIZE);
constant TLB_WAY_BITS : natural := log2(TLB_NUM_WAYS);
constant TLB_EA_TAG_BITS : natural := 64 - (TLB_LG_PGSZ + TLB_SET_BITS);
constant TLB_TAG_WAY_BITS : natural := TLB_NUM_WAYS * TLB_EA_TAG_BITS;
constant TLB_PTE_BITS : natural := 64;
constant TLB_PTE_WAY_BITS : natural := TLB_NUM_WAYS * TLB_PTE_BITS;

subtype tlb_way_t is integer range 0 to TLB_NUM_WAYS - 1;
subtype tlb_index_t is integer range 0 to TLB_SET_SIZE - 1;
subtype tlb_way_valids_t is std_ulogic_vector(TLB_NUM_WAYS-1 downto 0);
type tlb_valids_t is array(tlb_index_t) of tlb_way_valids_t;
subtype tlb_tag_t is std_ulogic_vector(TLB_EA_TAG_BITS - 1 downto 0);
subtype tlb_way_tags_t is std_ulogic_vector(TLB_TAG_WAY_BITS-1 downto 0);
type tlb_tags_t is array(tlb_index_t) of tlb_way_tags_t;
subtype tlb_pte_t is std_ulogic_vector(TLB_PTE_BITS - 1 downto 0);
subtype tlb_way_ptes_t is std_ulogic_vector(TLB_PTE_WAY_BITS-1 downto 0);
type tlb_ptes_t is array(tlb_index_t) of tlb_way_ptes_t;
type hit_way_set_t is array(tlb_way_t) of way_t;

signal dtlb_valids : tlb_valids_t;
signal dtlb_tags : tlb_tags_t;
signal dtlb_ptes : tlb_ptes_t;
attribute ram_style of dtlb_tags : signal is "distributed";
attribute ram_style of dtlb_ptes : signal is "distributed";

-- Record for storing permission, attribute, etc. bits from a PTE
type perm_attr_t is record
reference : std_ulogic;
changed : std_ulogic;
nocache : std_ulogic;
priv : std_ulogic;
rd_perm : std_ulogic;
wr_perm : std_ulogic;
end record;

function extract_perm_attr(pte : std_ulogic_vector(TLB_PTE_BITS - 1 downto 0)) return perm_attr_t is
variable pa : perm_attr_t;
begin
pa.reference := pte(8);
pa.changed := pte(7);
pa.nocache := pte(5);
pa.priv := pte(3);
pa.rd_perm := pte(2);
pa.wr_perm := pte(1);
return pa;
end;

constant real_mode_perm_attr : perm_attr_t := (nocache => '0', others => '1');

-- Type of operation on a "valid" input
type op_t is (OP_NONE,
@ -118,6 +179,7 @@ architecture rtl of dcache is
OP_LOAD_MISS, -- Load missing cache
OP_LOAD_NC, -- Non-cachable load
OP_BAD, -- BAD: Cache hit on NC load/store
OP_TLB_ERR, -- TLB miss or protection/RC failure
OP_STORE_HIT, -- Store hitting cache
OP_STORE_MISS); -- Store missing cache
@ -144,12 +206,25 @@ architecture rtl of dcache is
-- first stage emits a stall for a complex op.
--

-- Stage 0 register, basically contains just the latched request
type reg_stage_0_t is record
req : Loadstore1ToDcacheType;
tlbie : std_ulogic;
doall : std_ulogic;
tlbld : std_ulogic;
mmu_req : std_ulogic; -- indicates source of request
end record;

signal r0 : reg_stage_0_t;
signal r0_valid : std_ulogic;
-- First stage register, contains state for stage 1 of load hits
-- and for the state machine used by all other operations
--
type reg_stage_1_t is record
-- Latch the complete request from ls1
req : Loadstore1ToDcacheType;
mmu_req : std_ulogic;

-- Cache hit state
hit_way : way_t;
@ -168,6 +243,13 @@ architecture rtl of dcache is
store_way : way_t;
store_row : row_t;
store_index : index_t;

-- Signals to complete with error
error_done : std_ulogic;
cache_paradox : std_ulogic;

-- completion signal for tlbie
tlbie_done : std_ulogic;
end record;

signal r1 : reg_stage_1_t;
@ -208,6 +290,24 @@ architecture rtl of dcache is
-- Wishbone read/write/cache write formatting signals
signal bus_sel : std_ulogic_vector(7 downto 0);

-- TLB signals
signal tlb_tag_way : tlb_way_tags_t;
signal tlb_pte_way : tlb_way_ptes_t;
signal tlb_valid_way : tlb_way_valids_t;
signal tlb_req_index : tlb_index_t;
signal tlb_hit : std_ulogic;
signal tlb_hit_way : tlb_way_t;
signal pte : tlb_pte_t;
signal ra : std_ulogic_vector(REAL_ADDR_BITS - 1 downto 0);
signal valid_ra : std_ulogic;
signal perm_attr : perm_attr_t;
signal rc_ok : std_ulogic;
signal perm_ok : std_ulogic;

-- TLB PLRU output interface
type tlb_plru_out_t is array(tlb_index_t) of std_ulogic_vector(TLB_WAY_BITS-1 downto 0);
signal tlb_plru_victim : tlb_plru_out_t;

--
-- Helper functions to decode incoming requests
--
@ -215,13 +315,13 @@ architecture rtl of dcache is
-- Return the cache line index (tag index) for an address
function get_index(addr: std_ulogic_vector(63 downto 0)) return index_t is
begin
return to_integer(unsigned(addr(63-TAG_BITS downto LINE_OFF_BITS)));
return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto LINE_OFF_BITS)));
end;

-- Return the cache row index (data memory) for an address
function get_row(addr: std_ulogic_vector(63 downto 0)) return row_t is
begin
return to_integer(unsigned(addr(63-TAG_BITS downto ROW_OFF_BITS)));
return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto ROW_OFF_BITS)));
end;

-- Returns whether this is the last row of a line
@ -269,9 +369,9 @@ architecture rtl of dcache is
end;

-- Get the tag value from the address
function get_tag(addr: std_ulogic_vector(63 downto 0)) return cache_tag_t is
function get_tag(addr: std_ulogic_vector(REAL_ADDR_BITS - 1 downto 0)) return cache_tag_t is
begin
return addr(63 downto 64-TAG_BITS);
return addr(REAL_ADDR_BITS - 1 downto SET_SIZE_BITS);
end;

-- Read a tag from a tag memory row
@ -287,6 +387,38 @@ architecture rtl of dcache is
tagset((way+1) * TAG_BITS - 1 downto way * TAG_BITS) := tag;
end;

-- Read a TLB tag from a TLB tag memory row
function read_tlb_tag(way: tlb_way_t; tags: tlb_way_tags_t) return tlb_tag_t is
variable j : integer;
begin
j := way * TLB_EA_TAG_BITS;
return tags(j + TLB_EA_TAG_BITS - 1 downto j);
end;

-- Write a TLB tag to a TLB tag memory row
procedure write_tlb_tag(way: tlb_way_t; tags: inout tlb_way_tags_t;
tag: tlb_tag_t) is
variable j : integer;
begin
j := way * TLB_EA_TAG_BITS;
tags(j + TLB_EA_TAG_BITS - 1 downto j) := tag;
end;

-- Read a PTE from a TLB PTE memory row
function read_tlb_pte(way: tlb_way_t; ptes: tlb_way_ptes_t) return tlb_pte_t is
variable j : integer;
begin
j := way * TLB_PTE_BITS;
return ptes(j + TLB_PTE_BITS - 1 downto j);
end;

procedure write_tlb_pte(way: tlb_way_t; ptes: inout tlb_way_ptes_t; newpte: tlb_pte_t) is
variable j : integer;
begin
j := way * TLB_PTE_BITS;
ptes(j + TLB_PTE_BITS - 1 downto j) := newpte;
end;

begin

assert LINE_SIZE mod ROW_SIZE = 0 report "LINE_SIZE not multiple of ROW_SIZE" severity FAILURE;
@ -297,13 +429,188 @@ begin
report "geometry bits don't add up" severity FAILURE;
assert (LINE_OFF_BITS = ROW_OFF_BITS + ROW_LINEBITS)
report "geometry bits don't add up" severity FAILURE;
assert (64 = TAG_BITS + INDEX_BITS + LINE_OFF_BITS)
assert (REAL_ADDR_BITS = TAG_BITS + INDEX_BITS + LINE_OFF_BITS)
report "geometry bits don't add up" severity FAILURE;
assert (64 = TAG_BITS + ROW_BITS + ROW_OFF_BITS)
assert (REAL_ADDR_BITS = TAG_BITS + ROW_BITS + ROW_OFF_BITS)
report "geometry bits don't add up" severity FAILURE;
assert (64 = wishbone_data_bits)
report "Can't yet handle a wishbone width that isn't 64-bits" severity FAILURE;

-- Latch the request in r0.req as long as we're not stalling
stage_0 : process(clk)
begin
if rising_edge(clk) then
if rst = '1' then
r0.req.valid <= '0';
elsif stall_out = '0' then
assert (d_in.valid and m_in.valid) = '0' report
"request collision loadstore vs MMU";
if m_in.valid = '1' then
r0.req.valid <= '1';
r0.req.load <= not (m_in.tlbie or m_in.tlbld);
r0.req.dcbz <= '0';
r0.req.nc <= '0';
r0.req.reserve <= '0';
r0.req.virt_mode <= '0';
r0.req.priv_mode <= '1';
r0.req.addr <= m_in.addr;
r0.req.data <= m_in.pte;
r0.req.byte_sel <= (others => '1');
r0.tlbie <= m_in.tlbie;
r0.doall <= m_in.doall;
r0.tlbld <= m_in.tlbld;
r0.mmu_req <= '1';
else
r0.req <= d_in;
r0.tlbie <= '0';
r0.doall <= '0';
r0.tlbld <= '0';
r0.mmu_req <= '0';
end if;
end if;
end if;
end process;

-- we don't yet handle collisions between loadstore1 requests and MMU requests
m_out.stall <= '0';

-- Hold off the request in r0 when stalling,
-- and cancel it if we get an error in a previous request.
r0_valid <= r0.req.valid and not stall_out and not r1.error_done;

-- TLB
-- Operates in the second cycle on the request latched in r0.req.
-- TLB updates write the entry at the end of the second cycle.
tlb_read : process(clk)
variable index : tlb_index_t;
variable addrbits : std_ulogic_vector(TLB_SET_BITS - 1 downto 0);
begin
if rising_edge(clk) then
if stall_out = '1' then
-- keep reading the same thing while stalled
index := tlb_req_index;
else
if m_in.valid = '1' then
addrbits := m_in.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1 downto TLB_LG_PGSZ);
else
addrbits := d_in.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1 downto TLB_LG_PGSZ);
end if;
index := to_integer(unsigned(addrbits));
end if;
tlb_valid_way <= dtlb_valids(index);
tlb_tag_way <= dtlb_tags(index);
tlb_pte_way <= dtlb_ptes(index);
end if;
end process;

-- Generate TLB PLRUs
maybe_tlb_plrus: if TLB_NUM_WAYS > 1 generate
begin
tlb_plrus: for i in 0 to TLB_SET_SIZE - 1 generate
-- TLB PLRU interface
signal tlb_plru_acc : std_ulogic_vector(TLB_WAY_BITS-1 downto 0);
signal tlb_plru_acc_en : std_ulogic;
signal tlb_plru_out : std_ulogic_vector(TLB_WAY_BITS-1 downto 0);
begin
tlb_plru : entity work.plru
generic map (
BITS => TLB_WAY_BITS
)
port map (
clk => clk,
rst => rst,
acc => tlb_plru_acc,
acc_en => tlb_plru_acc_en,
lru => tlb_plru_out
);

process(tlb_req_index, tlb_hit, tlb_hit_way, tlb_plru_out)
begin
-- PLRU interface
if tlb_hit = '1' and tlb_req_index = i then
tlb_plru_acc_en <= '1';
else
tlb_plru_acc_en <= '0';
end if;
tlb_plru_acc <= std_ulogic_vector(to_unsigned(tlb_hit_way, TLB_WAY_BITS));
tlb_plru_victim(i) <= tlb_plru_out;
end process;
end generate;
end generate;

tlb_search : process(all)
variable hitway : tlb_way_t;
variable hit : std_ulogic;
variable eatag : tlb_tag_t;
begin
tlb_req_index <= to_integer(unsigned(r0.req.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1
downto TLB_LG_PGSZ)));
hitway := 0;
hit := '0';
eatag := r0.req.addr(63 downto TLB_LG_PGSZ + TLB_SET_BITS);
for i in tlb_way_t loop
if tlb_valid_way(i) = '1' and
read_tlb_tag(i, tlb_tag_way) = eatag then
hitway := i;
hit := '1';
end if;
end loop;
tlb_hit <= hit and r0_valid;
tlb_hit_way <= hitway;
if tlb_hit = '1' then
pte <= read_tlb_pte(hitway, tlb_pte_way);
else
pte <= (others => '0');
end if;
valid_ra <= tlb_hit or not r0.req.virt_mode;
if r0.req.virt_mode = '1' then
ra <= pte(REAL_ADDR_BITS - 1 downto TLB_LG_PGSZ) &
r0.req.addr(TLB_LG_PGSZ - 1 downto 0);
perm_attr <= extract_perm_attr(pte);
else
ra <= r0.req.addr(REAL_ADDR_BITS - 1 downto 0);
perm_attr <= real_mode_perm_attr;
end if;
end process;

tlb_update : process(clk)
variable tlbie : std_ulogic;
variable tlbwe : std_ulogic;
variable repl_way : tlb_way_t;
variable eatag : tlb_tag_t;
variable tagset : tlb_way_tags_t;
variable pteset : tlb_way_ptes_t;
begin
if rising_edge(clk) then
tlbie := r0_valid and r0.tlbie;
tlbwe := r0_valid and r0.tlbld;
if rst = '1' or (tlbie = '1' and r0.doall = '1') then
-- clear all valid bits at once
for i in tlb_index_t loop
dtlb_valids(i) <= (others => '0');
end loop;
elsif tlbie = '1' then
if tlb_hit = '1' then
dtlb_valids(tlb_req_index)(tlb_hit_way) <= '0';
end if;
elsif tlbwe = '1' then
if tlb_hit = '1' then
repl_way := tlb_hit_way;
else
repl_way := to_integer(unsigned(tlb_plru_victim(tlb_req_index)));
end if;
eatag := r0.req.addr(63 downto TLB_LG_PGSZ + TLB_SET_BITS);
tagset := tlb_tag_way;
write_tlb_tag(repl_way, tagset, eatag);
dtlb_tags(tlb_req_index) <= tagset;
pteset := tlb_pte_way;
write_tlb_pte(repl_way, pteset, r0.req.data);
dtlb_ptes(tlb_req_index) <= pteset;
dtlb_valids(tlb_req_index)(repl_way) <= '1';
end if;
end if;
end process;

-- Generate PLRUs
maybe_plrus: if NUM_WAYS > 1 generate
begin
@ -341,53 +648,74 @@ begin
end generate;
end generate;

-- Latch the request in r0 as long as we're not stalling
stage_0 : process(clk)
begin
if rising_edge(clk) then
if rst = '1' then
r0.valid <= '0';
elsif stall_out = '0' then
r0 <= d_in;
end if;
end if;
end process;

-- Cache request parsing and hit detection
dcache_request : process(all)
variable is_hit : std_ulogic;
variable hit_way : way_t;
variable op : op_t;
variable tmp : std_ulogic_vector(63 downto 0);
variable data : std_ulogic_vector(63 downto 0);
variable opsel : std_ulogic_vector(3 downto 0);
variable opsel : std_ulogic_vector(2 downto 0);
variable go : std_ulogic;
variable nc : std_ulogic;
variable s_hit : std_ulogic;
variable s_tag : cache_tag_t;
variable s_pte : tlb_pte_t;
variable s_ra : std_ulogic_vector(REAL_ADDR_BITS - 1 downto 0);
variable hit_set : std_ulogic_vector(TLB_NUM_WAYS - 1 downto 0);
variable hit_way_set : hit_way_set_t;
begin
-- Extract line, row and tag from request
req_index <= get_index(r0.addr);
req_row <= get_row(r0.addr);
req_tag <= get_tag(r0.addr);
req_index <= get_index(r0.req.addr);
req_row <= get_row(r0.req.addr);
req_tag <= get_tag(ra);

-- Only do anything if not being stalled by stage 1
go := r0.valid and not stall_out;
go := r0_valid and not (r0.tlbie or r0.tlbld);

-- Calculate address of beginning of cache line, will be
-- used for cache miss processing if needed
--
req_laddr <= r0.addr(63 downto LINE_OFF_BITS) &
req_laddr <= (63 downto REAL_ADDR_BITS => '0') &
ra(REAL_ADDR_BITS - 1 downto LINE_OFF_BITS) &
(LINE_OFF_BITS-1 downto 0 => '0');

-- Test if pending request is a hit on any way
hit_way := 0;
is_hit := '0';
for i in way_t loop
if go = '1' and cache_valids(req_index)(i) = '1' then
if read_tag(i, cache_tags(req_index)) = req_tag then
hit_way := i;
is_hit := '1';
end if;
end if;
end loop;
-- In order to make timing in virtual mode, when we are using the TLB,
-- we compare each way with each of the real addresses from each way of
-- the TLB, and then decide later which match to use.
hit_way := 0;
is_hit := '0';
if r0.req.virt_mode = '1' then
for j in tlb_way_t loop
hit_way_set(j) := 0;
s_hit := '0';
s_pte := read_tlb_pte(j, tlb_pte_way);
s_ra := s_pte(REAL_ADDR_BITS - 1 downto TLB_LG_PGSZ) &
r0.req.addr(TLB_LG_PGSZ - 1 downto 0);
s_tag := get_tag(s_ra);
for i in way_t loop
if go = '1' and cache_valids(req_index)(i) = '1' and
read_tag(i, cache_tags(req_index)) = s_tag and
tlb_valid_way(j) = '1' then
hit_way_set(j) := i;
s_hit := '1';
end if;
end loop;
hit_set(j) := s_hit;
end loop;
if tlb_hit = '1' then
is_hit := hit_set(tlb_hit_way);
hit_way := hit_way_set(tlb_hit_way);
end if;
else
s_tag := get_tag(r0.req.addr(REAL_ADDR_BITS - 1 downto 0));
for i in way_t loop
if go = '1' and cache_valids(req_index)(i) = '1' and
read_tag(i, cache_tags(req_index)) = s_tag then
hit_way := i;
is_hit := '1';
end if;
end loop;
end if;

-- The way that matched on a hit
req_hit_way <= hit_way;
@ -395,22 +723,35 @@ begin
-- The way to replace on a miss
replace_way <= to_integer(unsigned(plru_victim(req_index)));

-- Combine the request and cache his status to decide what
-- work out whether we have permission for this access
-- NB we don't yet implement AMR, thus no KUAP
rc_ok <= perm_attr.reference and (r0.req.load or perm_attr.changed);
perm_ok <= (r0.req.priv_mode or not perm_attr.priv) and
(perm_attr.wr_perm or (r0.req.load and perm_attr.rd_perm));

-- Combine the request and cache hit status to decide what
-- operation needs to be done
--
opsel := go & r0.load & r0.nc & is_hit;
case opsel is
when "1101" => op := OP_LOAD_HIT;
when "1100" => op := OP_LOAD_MISS;
when "1110" => op := OP_LOAD_NC;
when "1001" => op := OP_STORE_HIT;
when "1000" => op := OP_STORE_MISS;
when "1010" => op := OP_STORE_MISS;
when "1011" => op := OP_BAD;
when "1111" => op := OP_BAD;
when others => op := OP_NONE;
end case;

nc := r0.req.nc or perm_attr.nocache;
op := OP_NONE;
if go = '1' then
if valid_ra = '1' and rc_ok = '1' and perm_ok = '1' then
opsel := r0.req.load & nc & is_hit;
case opsel is
when "101" => op := OP_LOAD_HIT;
when "100" => op := OP_LOAD_MISS;
when "110" => op := OP_LOAD_NC;
when "001" => op := OP_STORE_HIT;
when "000" => op := OP_STORE_MISS;
when "010" => op := OP_STORE_MISS;
when "011" => op := OP_BAD;
when "111" => op := OP_BAD;
when others => op := OP_NONE;
end case;
else
op := OP_TLB_ERR;
end if;
end if;
req_op <= op;

-- Version of the row number that is valid one cycle earlier
@ -418,7 +759,11 @@ begin
-- If we're stalling then we need to keep reading the last
-- row requested.
if stall_out = '0' then
early_req_row <= get_row(d_in.addr);
if m_in.valid = '1' then
early_req_row <= get_row(m_in.addr);
else
early_req_row <= get_row(d_in.addr);
end if;
else
early_req_row <= req_row;
end if;
@ -427,9 +772,6 @@ begin
-- Wire up wishbone request latch out of stage 1
wishbone_out <= r1.wb;

-- TODO: Generate errors
-- err_nc_collision <= '1' when req_op = OP_BAD else '0';

-- Generate stalls from stage 1 state machine
stall_out <= '1' when r1.state /= IDLE else '0';

@ -439,17 +781,17 @@ begin
cancel_store <= '0';
set_rsrv <= '0';
clear_rsrv <= '0';
if stall_out = '0' and r0.valid = '1' and r0.reserve = '1' then
if r0_valid = '1' and r0.req.reserve = '1' then
-- XXX generate alignment interrupt if address is not aligned
-- XXX or if r0.nc = '1'
if r0.load = '1' then
-- XXX or if r0.req.nc = '1'
if r0.req.load = '1' then
-- load with reservation
set_rsrv <= '1';
else
-- store conditional
clear_rsrv <= '1';
if reservation.valid = '0' or
r0.addr(63 downto LINE_OFF_BITS) /= reservation.addr then
r0.req.addr(63 downto LINE_OFF_BITS) /= reservation.addr then
cancel_store <= '1';
end if;
end if;
@ -463,7 +805,7 @@ begin
reservation.valid <= '0';
elsif set_rsrv = '1' then
reservation.valid <= '1';
reservation.addr <= r0.addr(63 downto LINE_OFF_BITS);
reservation.addr <= r0.req.addr(63 downto LINE_OFF_BITS);
end if;
end if;
end process;
@ -477,6 +819,13 @@ begin
d_out.valid <= '0';
d_out.data <= cache_out(r1.hit_way);
d_out.store_done <= '0';
d_out.error <= '0';
d_out.cache_paradox <= '0';

-- Outputs to MMU
m_out.done <= r1.tlbie_done;
m_out.err <= '0';
m_out.data <= cache_out(r1.hit_way);

-- We have a valid load or store hit or we just completed a slow
-- op such as a load miss, a NC load or a store
@ -496,30 +845,63 @@ begin
"unexpected hit_load_delayed collision with slow_valid"
severity FAILURE;

-- Load hit case is the standard path
if r1.hit_load_valid = '1' then
report "completing load hit";
d_out.valid <= '1';
end if;
if r1.mmu_req = '0' then
-- Request came from loadstore1...
-- Load hit case is the standard path
if r1.hit_load_valid = '1' then
report "completing load hit";
d_out.valid <= '1';
end if;

-- Slow ops (load miss, NC, stores)
if r1.slow_valid = '1' then
-- If it's a load, enable register writeback and switch
-- mux accordingly
--
if r1.req.load then
-- Read data comes from the slow data latch
d_out.data <= r1.slow_data;
end if;
d_out.store_done <= '1';
-- error cases complete without stalling
if r1.error_done = '1' then
report "completing ld/st with error";
d_out.error <= '1';
d_out.cache_paradox <= r1.cache_paradox;
d_out.valid <= '1';
end if;

report "completing store or load miss";
d_out.valid <= '1';
end if;
-- Slow ops (load miss, NC, stores)
if r1.slow_valid = '1' then
-- If it's a load, enable register writeback and switch
-- mux accordingly
--
if r1.req.load then
-- Read data comes from the slow data latch
d_out.data <= r1.slow_data;
end if;
d_out.store_done <= '1';

report "completing store or load miss";
d_out.valid <= '1';
end if;

if r1.stcx_fail = '1' then
d_out.store_done <= '0';
d_out.valid <= '1';
end if;

else
-- Request came from MMU
if r1.hit_load_valid = '1' then
report "completing load hit to MMU, data=" & to_hstring(m_out.data);
m_out.done <= '1';
end if;

-- error cases complete without stalling
if r1.error_done = '1' then
report "completing MMU ld with error";
m_out.err <= '1';
m_out.done <= '1';
end if;

if r1.stcx_fail = '1' then
d_out.store_done <= '0';
d_out.valid <= '1';
-- Slow ops (i.e. load miss)
if r1.slow_valid = '1' then
-- Read data comes from the slow data latch
m_out.data <= r1.slow_data;
report "completing MMU load miss, data=" & to_hstring(m_out.data);
m_out.done <= '1';
end if;
end if;

end process;
@ -578,8 +960,8 @@ begin
if r1.state = IDLE then
-- In IDLE state, the only write path is the store-hit update case
wr_addr <= std_ulogic_vector(to_unsigned(req_row, ROW_BITS));
wr_data <= r0.data;
wr_sel <= r0.byte_sel;
wr_data <= r0.req.data;
wr_sel <= r0.req.byte_sel;
else
-- Otherwise, we might be doing a reload or a DCBZ
if r1.req.dcbz = '1' then
@ -609,21 +991,23 @@ begin

--
-- Cache hit synchronous machine for the easy case. This handles load hits.
-- It also handles error cases (TLB miss, cache paradox)
--
dcache_fast_hit : process(clk)
begin
if rising_edge(clk) then
-- If we have a request incoming, we have to latch it as r0.valid
-- If we have a request incoming, we have to latch it as r0.req.valid
-- is only set for a single cycle. It's up to the control logic to
-- ensure we don't override an uncompleted request (for now we are
-- single issue on load/stores so we are fine, later, we can generate
-- a stall output if necessary).

if req_op /= OP_NONE and stall_out = '0' then
r1.req <= r0;
r1.req <= r0.req;
r1.mmu_req <= r0.mmu_req;
report "op:" & op_t'image(req_op) &
" addr:" & to_hstring(r0.addr) &
" nc:" & std_ulogic'image(r0.nc) &
" addr:" & to_hstring(r0.req.addr) &
" nc:" & std_ulogic'image(r0.req.nc) &
" idx:" & integer'image(req_index) &
" tag:" & to_hstring(req_tag) &
" way: " & integer'image(req_hit_way);
@ -636,6 +1020,23 @@ begin
else
r1.hit_load_valid <= '0';
end if;

if req_op = OP_TLB_ERR then
report "Signalling ld/st error valid_ra=" & std_ulogic'image(valid_ra) &
" rc_ok=" & std_ulogic'image(rc_ok) & " perm_ok=" & std_ulogic'image(perm_ok);
r1.error_done <= '1';
r1.cache_paradox <= '0';
elsif req_op = OP_BAD then
report "Signalling cache paradox";
r1.error_done <= '1';
r1.cache_paradox <= '1';
else
r1.error_done <= '0';
r1.cache_paradox <= '0';
end if;

-- complete tlbies and TLB loads in the third cycle
r1.tlbie_done <= r0_valid and (r0.tlbie or r0.tlbld);
end if;
end process;

@ -681,7 +1082,7 @@ begin
when OP_LOAD_MISS =>
-- Normal load cache miss, start the reload machine
--
report "cache miss addr:" & to_hstring(r0.addr) &
report "cache miss addr:" & to_hstring(r0.req.addr) &
" idx:" & integer'image(req_index) &
" way:" & integer'image(replace_way) &
" tag:" & to_hstring(req_tag);
@ -716,18 +1117,18 @@ begin
r1.state <= RELOAD_WAIT_ACK;

when OP_LOAD_NC =>
r1.wb.sel <= r0.byte_sel;
r1.wb.adr <= r0.addr(r1.wb.adr'left downto 3) & "000";
r1.wb.sel <= r0.req.byte_sel;
r1.wb.adr <= ra(r1.wb.adr'left downto 3) & "000";
r1.wb.cyc <= '1';
r1.wb.stb <= '1';
r1.wb.we <= '0';
r1.state <= NC_LOAD_WAIT_ACK;

when OP_STORE_HIT | OP_STORE_MISS =>
if r0.dcbz = '0' then
r1.wb.sel <= r0.byte_sel;
r1.wb.adr <= r0.addr(r1.wb.adr'left downto 3) & "000";
r1.wb.dat <= r0.data;
if r0.req.dcbz = '0' then
r1.wb.sel <= r0.req.byte_sel;
r1.wb.adr <= ra(r1.wb.adr'left downto 3) & "000";
r1.wb.dat <= r0.req.data;
if cancel_store = '0' then
r1.wb.cyc <= '1';
r1.wb.stb <= '1';
@ -774,8 +1175,10 @@ begin
end if;

-- OP_NONE and OP_BAD do nothing
-- OP_BAD was handled above already
when OP_NONE =>
when OP_BAD =>
when OP_BAD =>
when OP_TLB_ERR =>
end case;

when RELOAD_WAIT_ACK =>

@ -15,6 +15,9 @@ architecture behave of dcache_tb is
signal d_in : Loadstore1ToDcacheType;
signal d_out : DcacheToLoadstore1Type;

signal m_in : MmuToDcacheType;
signal m_out : DcacheToMmuType;

signal wb_bram_in : wishbone_master_out;
signal wb_bram_out : wishbone_slave_out;

@ -30,6 +33,8 @@ begin
rst => rst,
d_in => d_in,
d_out => d_out,
m_in => m_in,
m_out => m_out,
wishbone_out => wb_bram_in,
wishbone_in => wb_bram_out
);
@ -71,6 +76,9 @@ begin
d_in.nc <= '0';
d_in.addr <= (others => '0');
d_in.data <= (others => '0');
m_in.valid <= '0';
m_in.addr <= (others => '0');
m_in.pte <= (others => '0');

wait for 4*clk_period;
wait until rising_edge(clk);

@ -181,11 +181,13 @@ architecture behaviour of decode1 is
2#1111101001# => (ALU, OP_DIV, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '1', RC, '0', '0'), -- divdo
2#0111101011# => (ALU, OP_DIV, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '1', RC, '0', '0'), -- divw
2#1111101011# => (ALU, OP_DIV, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '1', RC, '0', '0'), -- divwo
2#1101010110# => (ALU, OP_NOP, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- eieio
2#0100011100# => (ALU, OP_XOR, NONE, RB, RS, RA, '0', '0', '0', '1', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- eqv
2#1110111010# => (ALU, OP_EXTS, NONE, NONE, RS, RA, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- extsb
2#1110011010# => (ALU, OP_EXTS, NONE, NONE, RS, RA, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- extsh
2#1111011010# => (ALU, OP_EXTS, NONE, NONE, RS, RA, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- extsw
-- 2#110111101-# extswsli
2#1101111010# => (ALU, OP_EXTSWSLI, NONE, CONST_SH, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- extswsli
2#1101111011# => (ALU, OP_EXTSWSLI, NONE, CONST_SH, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- extswsli
2#1111010110# => (ALU, OP_ICBI, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- icbi
2#0000010110# => (ALU, OP_NOP, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- icbt
2#0000001111# => (ALU, OP_ISEL, RA_OR_ZERO, RB, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- isel
@ -247,7 +249,7 @@ architecture behaviour of decode1 is
-- 2#1001000000# mcrxrx
2#0000010011# => (ALU, OP_MFCR, NONE, NONE, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- mfcr/mfocrf
2#0001010011# => (ALU, OP_MFMSR, NONE, NONE, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- mfmsr
2#0101010011# => (ALU, OP_MFSPR, SPR, NONE, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- mfspr
2#0101010011# => (ALU, OP_MFSPR, SPR, NONE, RS, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- mfspr
2#0100001001# => (ALU, OP_MOD, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- modud
2#0100001011# => (ALU, OP_MOD, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '0', NONE, '0', '0'), -- moduw
2#1100001001# => (ALU, OP_MOD, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '1', NONE, '0', '0'), -- modsd
@ -280,6 +282,7 @@ architecture behaviour of decode1 is
2#0010111010# => (ALU, OP_PRTY, NONE, NONE, RS, RA, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- prtyd
2#0010011010# => (ALU, OP_PRTY, NONE, NONE, RS, RA, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- prtyw
-- 2#0010000000# setb
2#0111110010# => (LDST, OP_TLBIE, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- slbia
2#0000011011# => (ALU, OP_SHL, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- sld
2#0000011000# => (ALU, OP_SHL, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '0', RC, '0', '0'), -- slw
2#1100011010# => (ALU, OP_SHR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '1', NONE, '0', '0', '0', '0', '0', '1', RC, '0', '0'), -- srad
@ -321,6 +324,8 @@ architecture behaviour of decode1 is
2#1001010110# => (ALU, OP_NOP, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- sync
2#0001000100# => (ALU, OP_TRAP, RA, RB, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '1'), -- td
2#0000000100# => (ALU, OP_TRAP, RA, RB, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '0', NONE, '0', '1'), -- tw
2#0100110010# => (LDST, OP_TLBIE, NONE, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- tlbie
2#0100010010# => (LDST, OP_TLBIE, NONE, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- tlbiel
2#0100111100# => (ALU, OP_XOR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- xor
others => illegal_inst
);
@ -342,9 +347,10 @@ architecture behaviour of decode1 is
others => decode_rom_init
);

-- unit internal in1 in2 in3 out CR CR inv inv cry cry ldst BR sgn upd rsrv 32b sgn rc lk sgl
-- op in out A out in out len ext pipe
constant nop_instr : decode_rom_t := (ALU, OP_NOP, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0');
-- unit internal in1 in2 in3 out CR CR inv inv cry cry ldst BR sgn upd rsrv 32b sgn rc lk sgl
-- op in out A out in out len ext pipe
constant nop_instr : decode_rom_t := (ALU, OP_NOP, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0');
constant fetch_fail_inst: decode_rom_t := (LDST, OP_FETCH_FAILED, NONE, NONE, NONE, NONE, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0');

begin
decode1_0: process(clk)
@ -361,6 +367,7 @@ begin
variable v : Decode1ToDecode2Type;
variable majorop : major_opcode_t;
variable op_19_bits: std_ulogic_vector(2 downto 0);
variable sprn : spr_num_t;
begin
v := r;

@ -376,7 +383,15 @@ begin
end if;

majorop := unsigned(f_in.insn(31 downto 26));
if majorop = "011111" then
if f_in.fetch_failed = '1' then
v.valid := '1';
-- Only send down a single OP_FETCH_FAILED
if r.decode.insn_type = OP_FETCH_FAILED then
v.valid := '0';
end if;
v.decode := fetch_fail_inst;

elsif majorop = "011111" then
-- major opcode 31, lots of things
v.decode := decode_op_31_array(to_integer(unsigned(f_in.insn(10 downto 1))));

@ -427,10 +442,17 @@ begin
end if;
end if;
elsif v.decode.insn_type = OP_MFSPR or v.decode.insn_type = OP_MTSPR then
v.ispr1 := fast_spr_num(decode_spr_num(f_in.insn));
sprn := decode_spr_num(f_in.insn);
v.ispr1 := fast_spr_num(sprn);
-- Make slow SPRs single issue
if is_fast_spr(v.ispr1) = '0' then
v.decode.sgl_pipe := '1';
-- send MMU-related SPRs to loadstore1
case sprn is
when SPR_DAR | SPR_DSISR | SPR_PID | SPR_PRTBL =>
v.decode.unit := LDST;
when others =>
end case;
end if;
elsif v.decode.insn_type = OP_RFID then
report "PPC RFID";

@ -285,9 +285,9 @@ begin
decoded_reg_c := decode_input_reg_c (d_in.decode.input_reg_c, d_in.insn, r_in.read3_data);
decoded_reg_o := decode_output_reg (d_in.decode.output_reg_a, d_in.insn, d_in.ispr1);

r_out.read1_enable <= decoded_reg_a.reg_valid;
r_out.read2_enable <= decoded_reg_b.reg_valid;
r_out.read3_enable <= decoded_reg_c.reg_valid;
r_out.read1_enable <= decoded_reg_a.reg_valid and d_in.valid;
r_out.read2_enable <= decoded_reg_b.reg_valid and d_in.valid;
r_out.read3_enable <= decoded_reg_c.reg_valid and d_in.valid;

case d_in.decode.length is
when is1B =>

@ -16,8 +16,9 @@ package decode_types is
OP_POPCNT, OP_PRTY, OP_RFID,
OP_RLC, OP_RLCL, OP_RLCR, OP_SC, OP_SETB,
OP_SHL, OP_SHR,
OP_SYNC, OP_TRAP,
OP_XOR
OP_SYNC, OP_TLBIE, OP_TRAP,
OP_XOR,
OP_FETCH_FAILED
);
type input_reg_a_t is (NONE, RA, RA_OR_ZERO, SPR);
type input_reg_b_t is (NONE, RB, CONST_UI, CONST_SI, CONST_SI_HI, CONST_UI_HI, CONST_LI, CONST_BD, CONST_DS, CONST_M1, CONST_SH, CONST_SH32, SPR);

@ -23,6 +23,7 @@ entity execute1 is
stall_out : out std_ulogic;

e_in : in Decode2ToExecute1Type;
l_in : in Loadstore1ToExecute1Type;

i_in : in XicsToExecute1Type;

@ -32,6 +33,8 @@ entity execute1 is

e_out : out Execute1ToWritebackType;

dbg_msr_out : out std_ulogic_vector(63 downto 0);

icache_inval : out std_ulogic;
terminate_out : out std_ulogic
);
@ -49,6 +52,7 @@ architecture behaviour of execute1 is
slow_op_rc : std_ulogic;
slow_op_oe : std_ulogic;
slow_op_xerc : xer_common_t;
ldst_nia : std_ulogic_vector(63 downto 0);
end record;
constant reg_type_init : reg_type :=
(e => Execute1ToWritebackInit, lr_update => '0',
@ -63,6 +67,7 @@ architecture behaviour of execute1 is
signal ctrl: ctrl_t := (irq_state => WRITE_SRR0, others => (others => '0'));
signal ctrl_tmp: ctrl_t := (irq_state => WRITE_SRR0, others => (others => '0'));
signal right_shift, rot_clear_left, rot_clear_right: std_ulogic;
signal rot_sign_ext: std_ulogic;
signal rotator_result: std_ulogic_vector(63 downto 0);
signal rotator_carry: std_ulogic;
signal logical_result: std_ulogic_vector(63 downto 0);
@ -85,6 +90,7 @@ architecture behaviour of execute1 is
OP_MFMSR => SUPER,
OP_MTMSRD => SUPER,
OP_RFID => SUPER,
OP_TLBIE => SUPER,
others => USER
);

@ -174,6 +180,7 @@ begin
arith => e_in.is_signed,
clear_left => rot_clear_left,
clear_right => rot_clear_right,
sign_ext_rs => rot_sign_ext,
result => rotator_result,
carry_out => rotator_carry
);
@ -215,6 +222,8 @@ begin
d_out => divider_to_x
);

dbg_msr_out <= ctrl.msr;

a_in <= r.e.write_data when EX1_BYPASS and e_in.bypass_data1 = '1' else e_in.read_data1;
b_in <= r.e.write_data when EX1_BYPASS and e_in.bypass_data2 = '1' else e_in.read_data2;
c_in <= r.e.write_data when EX1_BYPASS and e_in.bypass_data3 = '1' else e_in.read_data3;
@ -421,6 +430,9 @@ begin
icache_inval <= '0';
stall_out <= '0';
f_out <= Execute1ToFetch1TypeInit;
-- send MSR[IR] and ~MSR[PR] up to fetch1
f_out.virt_mode <= ctrl.msr(MSR_IR);
f_out.priv_mode <= not ctrl.msr(MSR_PR);

-- Next insn adder used in a couple of places
next_nia := std_ulogic_vector(unsigned(e_in.nia) + 4);
@ -429,6 +441,7 @@ begin
right_shift <= '1' when e_in.insn_type = OP_SHR else '0';
rot_clear_left <= '1' when e_in.insn_type = OP_RLC or e_in.insn_type = OP_RLCL else '0';
rot_clear_right <= '1' when e_in.insn_type = OP_RLC or e_in.insn_type = OP_RLCR else '0';
rot_sign_ext <= '1' when e_in.insn_type = OP_EXTSWSLI else '0';

ctrl_tmp.irq_state <= WRITE_SRR0;
exception := '0';
@ -438,9 +451,9 @@ begin
v.e.exc_write_reg := fast_spr_num(SPR_SRR0);
v.e.exc_write_data := e_in.nia;

if ctrl.irq_state = WRITE_SRR1 then
v.e.exc_write_reg := fast_spr_num(SPR_SRR1);
v.e.exc_write_data := ctrl.srr1;
if ctrl.irq_state = WRITE_SRR1 then
v.e.exc_write_reg := fast_spr_num(SPR_SRR1);
v.e.exc_write_data := ctrl.srr1;
v.e.exc_write_enable := '1';
ctrl_tmp.msr(MSR_SF) <= '1';
ctrl_tmp.msr(MSR_EE) <= '0';
@ -450,13 +463,15 @@ begin
ctrl_tmp.msr(MSR_RI) <= '0';
ctrl_tmp.msr(MSR_LE) <= '1';
f_out.redirect <= '1';
f_out.virt_mode <= '0';
f_out.priv_mode <= '1';
f_out.redirect_nia <= ctrl.irq_nia;
v.e.valid := e_in.valid;
report "Writing SRR1: " & to_hstring(ctrl.srr1);

elsif irq_valid = '1' and e_in.valid = '1' then
-- we need two cycles to write srr0 and 1
-- will need more when we have to write DSISR, DAR and HIER
-- will need more when we have to write HEIR
-- Don't deliver the interrupt until we have a valid instruction
-- coming in, so we have a valid NIA to put in SRR0.
exception := '1';
@ -487,13 +502,12 @@ begin

when OP_ILLEGAL =>
-- we need two cycles to write srr0 and 1
-- will need more when we have to write DSISR, DAR and HIER
-- will need more when we have to write HEIR
illegal := '1';
when OP_SC =>
-- check bit 1 of the instruction is 1 so we know this is sc;
-- 0 would mean scv, so generate an illegal instruction interrupt
-- we need two cycles to write srr0 and 1
-- will need more when we have to write DSISR, DAR and HIER
if e_in.insn(1) = '1' then
exception := '1';
exception_nextpc := '1';
@ -642,6 +656,8 @@ begin

when OP_RFID =>
f_out.redirect <= '1';
f_out.virt_mode <= b_in(MSR_IR) or b_in(MSR_PR);
f_out.priv_mode <= not b_in(MSR_PR);
f_out.redirect_nia <= a_in(63 downto 2) & "00"; -- srr0
-- Can't use msr_copy here because the partial function MSR
-- bits should be left unchanged, not zeroed.
@ -732,6 +748,7 @@ begin
when OP_MFSPR =>
report "MFSPR to SPR " & integer'image(decode_spr_num(e_in.insn)) &
"=" & to_hstring(a_in);
result_en := '1';
if is_fast_spr(e_in.read_reg1) then
result := a_in;
if decode_spr_num(e_in.insn) = SPR_XER then
@ -750,11 +767,15 @@ begin
result := ctrl.tb;
when SPR_DEC =>
result := ctrl.dec;
when others =>
result := (others => '0');
when others =>
-- mfspr from unimplemented SPRs should be a nop in
-- supervisor mode and a program interrupt for user mode
result := c_in;
if ctrl.msr(MSR_PR) = '1' then
illegal := '1';
end if;
end case;
end if;
result_en := '1';
when OP_MFCR =>