mirror of
https://github.com/antonblanchard/microwatt.git
synced 2026-01-28 12:39:16 +00:00
Merge pull request #396 from paulusmack/reduce-meta
Reduce metavalue warnings
This commit is contained in:
@@ -53,12 +53,14 @@ begin
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for i in 0 to WIDTH/BYTEWID-1 loop
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lbit := i * BYTEWID;
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mbit := lbit + BYTEWID - 1;
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widx := to_integer(unsigned(wr_addr));
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if wr_sel(i) = '1' then
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assert not is_X(wr_addr);
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widx := to_integer(unsigned(wr_addr));
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ram(widx)(mbit downto lbit) <= wr_data(mbit downto lbit);
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end if;
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end loop;
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if rd_en = '1' then
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assert not is_X(rd_addr);
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rd_data0 <= ram(to_integer(unsigned(rd_addr)));
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if TRACE then
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report "read a:" & to_hstring(rd_addr) &
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@@ -173,6 +173,7 @@ begin
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terminated <= '0';
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log_trigger_delay <= 0;
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gspr_index <= (others => '0');
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log_dmi_addr <= (others => '0');
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else
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if do_log_trigger = '1' or log_trigger_delay /= 0 then
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if log_trigger_delay = 255 or
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@@ -334,6 +335,7 @@ begin
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addr : std_ulogic_vector(31 downto 0)) return std_ulogic_vector is
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variable firstbit : integer;
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begin
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assert not is_X(addr);
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firstbit := to_integer(unsigned(addr(1 downto 0))) * 64;
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return data(firstbit + 63 downto firstbit);
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end;
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@@ -351,9 +353,14 @@ begin
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begin
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if rising_edge(clk) then
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if log_wr_enable = '1' then
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assert not is_X(log_wr_ptr);
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log_array(to_integer(log_wr_ptr)) <= log_data;
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end if;
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log_rd <= log_array(to_integer(log_rd_ptr_latched));
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if is_X(log_rd_ptr_latched) then
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log_rd <= (others => 'X');
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else
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log_rd <= log_array(to_integer(log_rd_ptr_latched));
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end if;
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end if;
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end process;
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@@ -366,6 +373,7 @@ begin
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if rst = '1' then
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log_wr_ptr <= (others => '0');
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log_toggle <= '0';
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log_rd_ptr_latched <= (others => '0');
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elsif log_wr_enable = '1' then
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if log_wr_ptr = to_unsigned(LOG_LENGTH - 1, LOG_INDEX_BITS) then
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log_toggle <= not log_toggle;
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274
dcache.vhdl
274
dcache.vhdl
@@ -97,9 +97,9 @@ architecture rtl of dcache is
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-- .. |-----| | INDEX_BITS (5)
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-- .. --------| | TAG_BITS (45)
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subtype row_t is integer range 0 to BRAM_ROWS-1;
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subtype index_t is integer range 0 to NUM_LINES-1;
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subtype way_t is integer range 0 to NUM_WAYS-1;
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subtype row_t is unsigned(ROW_BITS-1 downto 0);
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subtype index_t is unsigned(INDEX_BITS-1 downto 0);
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subtype way_t is unsigned(WAY_BITS-1 downto 0);
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subtype row_in_line_t is unsigned(ROW_LINEBITS-1 downto 0);
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-- The cache data BRAM organized as described above for each way
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@@ -110,14 +110,14 @@ architecture rtl of dcache is
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-- memory. For now, work around it by putting all the tags
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subtype cache_tag_t is std_logic_vector(TAG_BITS-1 downto 0);
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-- type cache_tags_set_t is array(way_t) of cache_tag_t;
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-- type cache_tags_array_t is array(index_t) of cache_tags_set_t;
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-- type cache_tags_array_t is array(0 to NUM_LINES-1) of cache_tags_set_t;
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constant TAG_RAM_WIDTH : natural := TAG_WIDTH * NUM_WAYS;
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subtype cache_tags_set_t is std_logic_vector(TAG_RAM_WIDTH-1 downto 0);
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type cache_tags_array_t is array(index_t) of cache_tags_set_t;
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type cache_tags_array_t is array(0 to NUM_LINES-1) of cache_tags_set_t;
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-- The cache valid bits
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subtype cache_way_valids_t is std_ulogic_vector(NUM_WAYS-1 downto 0);
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type cache_valids_t is array(index_t) of cache_way_valids_t;
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type cache_valids_t is array(0 to NUM_LINES-1) of cache_way_valids_t;
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type row_per_line_valid_t is array(0 to ROW_PER_LINE - 1) of std_ulogic;
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-- Storage. Hopefully implemented in LUTs
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@@ -137,7 +137,9 @@ architecture rtl of dcache is
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constant TLB_PTE_WAY_BITS : natural := TLB_NUM_WAYS * TLB_PTE_BITS;
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subtype tlb_way_t is integer range 0 to TLB_NUM_WAYS - 1;
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subtype tlb_way_sig_t is unsigned(TLB_WAY_BITS-1 downto 0);
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subtype tlb_index_t is integer range 0 to TLB_SET_SIZE - 1;
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subtype tlb_index_sig_t is unsigned(TLB_SET_BITS-1 downto 0);
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subtype tlb_way_valids_t is std_ulogic_vector(TLB_NUM_WAYS-1 downto 0);
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type tlb_valids_t is array(tlb_index_t) of tlb_way_valids_t;
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subtype tlb_tag_t is std_ulogic_vector(TLB_EA_TAG_BITS - 1 downto 0);
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@@ -312,8 +314,8 @@ architecture rtl of dcache is
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-- TLB hit state
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tlb_hit : std_ulogic;
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tlb_hit_way : tlb_way_t;
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tlb_hit_index : tlb_index_t;
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tlb_hit_way : tlb_way_sig_t;
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tlb_hit_index : tlb_index_sig_t;
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-- data buffer for data forwarded from writes to reads
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forward_data : std_ulogic_vector(63 downto 0);
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@@ -366,7 +368,6 @@ architecture rtl of dcache is
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-- Async signals on incoming request
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signal req_index : index_t;
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signal req_row : row_t;
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signal req_hit_way : way_t;
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signal req_tag : cache_tag_t;
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signal req_op : op_t;
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@@ -375,6 +376,7 @@ architecture rtl of dcache is
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signal req_go : std_ulogic;
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signal early_req_row : row_t;
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signal early_rd_valid : std_ulogic;
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signal cancel_store : std_ulogic;
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signal set_rsrv : std_ulogic;
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@@ -389,13 +391,13 @@ architecture rtl of dcache is
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signal use_forward2 : std_ulogic;
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-- Cache RAM interface
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type cache_ram_out_t is array(way_t) of cache_row_t;
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type cache_ram_out_t is array(0 to NUM_WAYS-1) of cache_row_t;
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signal cache_out : cache_ram_out_t;
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signal ram_wr_data : cache_row_t;
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signal ram_wr_select : std_ulogic_vector(ROW_SIZE - 1 downto 0);
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-- PLRU output interface
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type plru_out_t is array(index_t) of std_ulogic_vector(WAY_BITS-1 downto 0);
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type plru_out_t is array(0 to NUM_LINES-1) of std_ulogic_vector(WAY_BITS-1 downto 0);
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signal plru_victim : plru_out_t;
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signal replace_way : way_t;
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@@ -406,9 +408,10 @@ architecture rtl of dcache is
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signal tlb_tag_way : tlb_way_tags_t;
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signal tlb_pte_way : tlb_way_ptes_t;
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signal tlb_valid_way : tlb_way_valids_t;
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signal tlb_req_index : tlb_index_t;
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signal tlb_req_index : tlb_index_sig_t;
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signal tlb_read_valid : std_ulogic;
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signal tlb_hit : std_ulogic;
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signal tlb_hit_way : tlb_way_t;
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signal tlb_hit_way : tlb_way_sig_t;
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signal pte : tlb_pte_t;
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signal ra : real_addr_t;
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signal valid_ra : std_ulogic;
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@@ -434,21 +437,19 @@ architecture rtl of dcache is
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-- Return the cache line index (tag index) for an address
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function get_index(addr: std_ulogic_vector) return index_t is
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begin
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return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto LINE_OFF_BITS)));
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return unsigned(addr(SET_SIZE_BITS - 1 downto LINE_OFF_BITS));
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end;
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-- Return the cache row index (data memory) for an address
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function get_row(addr: std_ulogic_vector) return row_t is
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begin
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return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto ROW_OFF_BITS)));
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return unsigned(addr(SET_SIZE_BITS - 1 downto ROW_OFF_BITS));
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end;
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-- Return the index of a row within a line
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function get_row_of_line(row: row_t) return row_in_line_t is
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variable row_v : unsigned(ROW_BITS-1 downto 0);
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begin
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row_v := to_unsigned(row, ROW_BITS);
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return row_v(ROW_LINEBITS-1 downto 0);
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return row(ROW_LINEBITS-1 downto 0);
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end;
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-- Returns whether this is the last row of a line
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@@ -485,10 +486,10 @@ architecture rtl of dcache is
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variable row_idx : std_ulogic_vector(ROW_LINEBITS-1 downto 0);
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variable result : std_ulogic_vector(ROW_BITS-1 downto 0);
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begin
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row_v := std_ulogic_vector(to_unsigned(row, ROW_BITS));
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row_v := std_ulogic_vector(row);
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row_idx := row_v(ROW_LINEBITS-1 downto 0);
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row_v(ROW_LINEBITS-1 downto 0) := std_ulogic_vector(unsigned(row_idx) + 1);
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return to_integer(unsigned(row_v));
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return unsigned(row_v);
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end;
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-- Get the tag value from the address
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@@ -498,7 +499,7 @@ architecture rtl of dcache is
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end;
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-- Read a tag from a tag memory row
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function read_tag(way: way_t; tagset: cache_tags_set_t) return cache_tag_t is
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function read_tag(way: integer; tagset: cache_tags_set_t) return cache_tag_t is
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begin
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return tagset(way * TAG_WIDTH + TAG_BITS - 1 downto way * TAG_WIDTH);
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end;
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@@ -586,6 +587,9 @@ begin
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r.mmu_req := '0';
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r.d_valid := '0';
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end if;
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if r.req.valid = '1' and r.doall = '0' then
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assert not is_X(r.req.addr) severity failure;
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end if;
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if rst = '1' then
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r0_full <= '0';
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elsif r1.full = '0' and d_in.hold = '0' then
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@@ -617,21 +621,30 @@ begin
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tlb_read : process(clk)
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variable index : tlb_index_t;
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variable addrbits : std_ulogic_vector(TLB_SET_BITS - 1 downto 0);
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variable valid : std_ulogic;
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begin
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if rising_edge(clk) then
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if m_in.valid = '1' then
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addrbits := m_in.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1 downto TLB_LG_PGSZ);
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valid := not (m_in.tlbie and m_in.doall);
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else
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addrbits := d_in.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1 downto TLB_LG_PGSZ);
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valid := d_in.valid;
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end if;
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index := to_integer(unsigned(addrbits));
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-- If we have any op and the previous op isn't finished,
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-- then keep the same output for next cycle.
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if r0_stall = '0' then
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if r0_stall = '0' and valid = '1' then
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assert not is_X(addrbits);
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index := to_integer(unsigned(addrbits));
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tlb_valid_way <= dtlb_valids(index);
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tlb_tag_way <= dtlb_tags(index);
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tlb_pte_way <= dtlb_ptes(index);
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end if;
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if rst = '1' then
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tlb_read_valid <= '0';
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elsif r0_stall = '0' then
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tlb_read_valid <= valid;
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end if;
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end if;
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end process;
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@@ -659,38 +672,39 @@ begin
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process(all)
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begin
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-- PLRU interface
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if r1.tlb_hit_index = i then
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if not is_X(r1.tlb_hit_index) and r1.tlb_hit_index = i then
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tlb_plru_acc_en <= r1.tlb_hit;
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assert not is_X(r1.tlb_hit_way);
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else
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tlb_plru_acc_en <= '0';
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end if;
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tlb_plru_acc <= std_ulogic_vector(to_unsigned(r1.tlb_hit_way, TLB_WAY_BITS));
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tlb_plru_acc <= std_ulogic_vector(r1.tlb_hit_way);
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tlb_plru_victim(i) <= tlb_plru_out;
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end process;
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end generate;
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end generate;
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tlb_search : process(all)
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variable hitway : tlb_way_t;
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variable hitway : tlb_way_sig_t;
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variable hit : std_ulogic;
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variable eatag : tlb_tag_t;
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begin
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tlb_req_index <= to_integer(unsigned(r0.req.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1
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downto TLB_LG_PGSZ)));
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hitway := 0;
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tlb_req_index <= unsigned(r0.req.addr(TLB_LG_PGSZ + TLB_SET_BITS - 1
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downto TLB_LG_PGSZ));
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hitway := to_unsigned(0, TLB_WAY_BITS);
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hit := '0';
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eatag := r0.req.addr(63 downto TLB_LG_PGSZ + TLB_SET_BITS);
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for i in tlb_way_t loop
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if tlb_valid_way(i) = '1' and
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if tlb_read_valid = '1' and tlb_valid_way(i) = '1' and
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read_tlb_tag(i, tlb_tag_way) = eatag then
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hitway := i;
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hitway := to_unsigned(i, TLB_WAY_BITS);
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hit := '1';
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end if;
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end loop;
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tlb_hit <= hit and r0_valid;
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tlb_hit_way <= hitway;
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if tlb_hit = '1' then
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pte <= read_tlb_pte(hitway, tlb_pte_way);
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pte <= read_tlb_pte(to_integer(hitway), tlb_pte_way);
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else
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pte <= (others => '0');
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end if;
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@@ -711,7 +725,7 @@ begin
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tlb_update : process(clk)
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variable tlbie : std_ulogic;
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variable tlbwe : std_ulogic;
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variable repl_way : tlb_way_t;
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variable repl_way : tlb_way_sig_t;
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variable eatag : tlb_tag_t;
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variable tagset : tlb_way_tags_t;
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variable pteset : tlb_way_ptes_t;
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@@ -727,22 +741,27 @@ begin
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end loop;
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elsif tlbie = '1' then
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if tlb_hit = '1' then
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dtlb_valids(tlb_req_index)(tlb_hit_way) <= '0';
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assert not is_X(tlb_req_index);
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assert not is_X(tlb_hit_way);
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dtlb_valids(to_integer(tlb_req_index))(to_integer(tlb_hit_way)) <= '0';
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end if;
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elsif tlbwe = '1' then
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assert not is_X(tlb_req_index);
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if tlb_hit = '1' then
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repl_way := tlb_hit_way;
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else
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repl_way := to_integer(unsigned(tlb_plru_victim(tlb_req_index)));
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assert not is_X(tlb_plru_victim(to_integer(tlb_req_index)));
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repl_way := unsigned(tlb_plru_victim(to_integer(tlb_req_index)));
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end if;
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assert not is_X(repl_way);
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eatag := r0.req.addr(63 downto TLB_LG_PGSZ + TLB_SET_BITS);
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tagset := tlb_tag_way;
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write_tlb_tag(repl_way, tagset, eatag);
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dtlb_tags(tlb_req_index) <= tagset;
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write_tlb_tag(to_integer(repl_way), tagset, eatag);
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dtlb_tags(to_integer(tlb_req_index)) <= tagset;
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pteset := tlb_pte_way;
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write_tlb_pte(repl_way, pteset, r0.req.data);
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dtlb_ptes(tlb_req_index) <= pteset;
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dtlb_valids(tlb_req_index)(repl_way) <= '1';
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write_tlb_pte(to_integer(repl_way), pteset, r0.req.data);
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dtlb_ptes(to_integer(tlb_req_index)) <= pteset;
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dtlb_valids(to_integer(tlb_req_index))(to_integer(repl_way)) <= '1';
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end if;
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end if;
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end process;
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@@ -772,12 +791,12 @@ begin
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process(all)
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begin
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-- PLRU interface
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if r1.hit_index = i then
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if not is_X(r1.hit_index) and r1.hit_index = to_unsigned(i, INDEX_BITS) then
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plru_acc_en <= r1.cache_hit;
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else
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plru_acc_en <= '0';
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end if;
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plru_acc <= std_ulogic_vector(to_unsigned(r1.hit_way, WAY_BITS));
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plru_acc <= std_ulogic_vector(r1.hit_way);
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plru_victim(i) <= plru_out;
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end process;
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end generate;
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@@ -786,16 +805,24 @@ begin
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-- Cache tag RAM read port
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cache_tag_read : process(clk)
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variable index : index_t;
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variable valid : std_ulogic;
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begin
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if rising_edge(clk) then
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if r0_stall = '1' then
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index := req_index;
|
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valid := r0.req.valid and not (r0.tlbie or r0.tlbld);
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elsif m_in.valid = '1' then
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index := get_index(m_in.addr);
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valid := not (m_in.tlbie or m_in.tlbld);
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else
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index := get_index(d_in.addr);
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valid := d_in.valid;
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end if;
|
||||
if valid = '1' then
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||||
cache_tag_set <= cache_tags(to_integer(index));
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else
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cache_tag_set <= (others => '0');
|
||||
end if;
|
||||
cache_tag_set <= cache_tags(index);
|
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end if;
|
||||
end process;
|
||||
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||||
@@ -804,20 +831,25 @@ begin
|
||||
variable addr : real_addr_t;
|
||||
begin
|
||||
if rising_edge(clk) then
|
||||
addr := addr_to_real(wb_to_addr(snoop_in.adr));
|
||||
snoop_tag_set <= cache_tags(get_index(addr));
|
||||
snoop_wrtag <= get_tag(addr);
|
||||
snoop_index <= get_index(addr);
|
||||
-- Don't snoop our own cycles
|
||||
snoop_valid <= '0';
|
||||
if not (r1.wb.cyc = '1' and wishbone_in.stall = '0') then
|
||||
snoop_valid <= snoop_in.cyc and snoop_in.stb and snoop_in.we;
|
||||
if (snoop_in.cyc and snoop_in.stb and snoop_in.we) = '1' then
|
||||
snoop_valid <= '1';
|
||||
addr := addr_to_real(wb_to_addr(snoop_in.adr));
|
||||
assert not is_X(addr);
|
||||
snoop_tag_set <= cache_tags(to_integer(get_index(addr)));
|
||||
snoop_wrtag <= get_tag(addr);
|
||||
snoop_index <= get_index(addr);
|
||||
end if;
|
||||
end if;
|
||||
end if;
|
||||
end process;
|
||||
|
||||
-- Cache request parsing and hit detection
|
||||
dcache_request : process(all)
|
||||
variable req_row : row_t;
|
||||
variable rindex : index_t;
|
||||
variable is_hit : std_ulogic;
|
||||
variable hit_way : way_t;
|
||||
variable op : op_t;
|
||||
@@ -836,17 +868,24 @@ begin
|
||||
variable fwd_match : std_ulogic;
|
||||
begin
|
||||
-- Extract line, row and tag from request
|
||||
req_index <= get_index(r0.req.addr);
|
||||
req_row <= get_row(r0.req.addr);
|
||||
rindex := get_index(r0.req.addr);
|
||||
req_index <= rindex;
|
||||
req_row := get_row(r0.req.addr);
|
||||
req_tag <= get_tag(ra);
|
||||
|
||||
go := r0_valid and not (r0.tlbie or r0.tlbld) and not r1.ls_error;
|
||||
if is_X(r0.req.addr) then
|
||||
go := '0';
|
||||
end if;
|
||||
if go = '1' then
|
||||
assert not is_X(r1.forward_tag);
|
||||
end if;
|
||||
|
||||
-- Test if pending request is a hit on any way
|
||||
-- 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;
|
||||
hit_way := to_unsigned(0, WAY_BITS);
|
||||
is_hit := '0';
|
||||
rel_match := '0';
|
||||
fwd_match := '0';
|
||||
@@ -854,47 +893,54 @@ begin
|
||||
rel_matches := (others => '0');
|
||||
fwd_matches := (others => '0');
|
||||
for j in tlb_way_t loop
|
||||
hit_way_set(j) := 0;
|
||||
hit_way_set(j) := to_unsigned(0, WAY_BITS);
|
||||
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
|
||||
if go = '1' then
|
||||
assert not is_X(s_tag);
|
||||
end if;
|
||||
for i in 0 to NUM_WAYS-1 loop
|
||||
if go = '1' and cache_valids(to_integer(rindex))(i) = '1' and
|
||||
read_tag(i, cache_tag_set) = s_tag and
|
||||
tlb_valid_way(j) = '1' then
|
||||
hit_way_set(j) := i;
|
||||
hit_way_set(j) := to_unsigned(i, WAY_BITS);
|
||||
s_hit := '1';
|
||||
end if;
|
||||
end loop;
|
||||
hit_set(j) := s_hit;
|
||||
if s_tag = r1.reload_tag then
|
||||
if go = '1' and not is_X(r1.reload_tag) and s_tag = r1.reload_tag then
|
||||
rel_matches(j) := '1';
|
||||
end if;
|
||||
if s_tag = r1.forward_tag then
|
||||
if go = '1' and s_tag = r1.forward_tag then
|
||||
fwd_matches(j) := '1';
|
||||
end if;
|
||||
end loop;
|
||||
if tlb_hit = '1' then
|
||||
is_hit := hit_set(tlb_hit_way);
|
||||
hit_way := hit_way_set(tlb_hit_way);
|
||||
rel_match := rel_matches(tlb_hit_way);
|
||||
fwd_match := fwd_matches(tlb_hit_way);
|
||||
if tlb_hit = '1' and go = '1' then
|
||||
assert not is_X(tlb_hit_way);
|
||||
is_hit := hit_set(to_integer(tlb_hit_way));
|
||||
hit_way := hit_way_set(to_integer(tlb_hit_way));
|
||||
rel_match := rel_matches(to_integer(tlb_hit_way));
|
||||
fwd_match := fwd_matches(to_integer(tlb_hit_way));
|
||||
end if;
|
||||
else
|
||||
s_tag := get_tag(r0.req.addr);
|
||||
for i in way_t loop
|
||||
if go = '1' and cache_valids(req_index)(i) = '1' and
|
||||
if go = '1' then
|
||||
assert not is_X(s_tag);
|
||||
end if;
|
||||
for i in 0 to NUM_WAYS-1 loop
|
||||
if go = '1' and cache_valids(to_integer(rindex))(i) = '1' and
|
||||
read_tag(i, cache_tag_set) = s_tag then
|
||||
hit_way := i;
|
||||
hit_way := to_unsigned(i, WAY_BITS);
|
||||
is_hit := '1';
|
||||
end if;
|
||||
end loop;
|
||||
if s_tag = r1.reload_tag then
|
||||
if go = '1' and not is_X(r1.reload_tag) and s_tag = r1.reload_tag then
|
||||
rel_match := '1';
|
||||
end if;
|
||||
if s_tag = r1.forward_tag then
|
||||
if go = '1' and s_tag = r1.forward_tag then
|
||||
fwd_match := '1';
|
||||
end if;
|
||||
end if;
|
||||
@@ -904,7 +950,11 @@ begin
|
||||
-- Whether to use forwarded data for a load or not
|
||||
use_forward_st <= '0';
|
||||
use_forward_rl <= '0';
|
||||
if r1.store_row = req_row and rel_match = '1' then
|
||||
if rel_match = '1' then
|
||||
assert not is_X(r1.store_row);
|
||||
assert not is_X(req_row);
|
||||
end if;
|
||||
if rel_match = '1' and r1.store_row = req_row then
|
||||
-- Use the forwarding path if this cycle is a write to this row
|
||||
use_forward_st <= r1.write_bram;
|
||||
if r1.state = RELOAD_WAIT_ACK and wishbone_in.ack = '1' then
|
||||
@@ -912,27 +962,39 @@ begin
|
||||
end if;
|
||||
end if;
|
||||
use_forward2 <= '0';
|
||||
if r1.forward_row = req_row and fwd_match = '1' then
|
||||
if fwd_match = '1' then
|
||||
assert not is_X(r1.forward_row);
|
||||
if is_X(req_row) then
|
||||
report "req_row=" & to_hstring(req_row) & " addr=" & to_hstring(r0.req.addr) & " go=" & std_ulogic'image(go);
|
||||
end if;
|
||||
assert not is_X(req_row);
|
||||
end if;
|
||||
if fwd_match = '1' and r1.forward_row = req_row then
|
||||
use_forward2 <= r1.forward_valid;
|
||||
end if;
|
||||
|
||||
-- The way to replace on a miss
|
||||
if r1.write_tag = '1' then
|
||||
replace_way <= to_integer(unsigned(plru_victim(r1.store_index)));
|
||||
assert not is_X(r1.store_index);
|
||||
replace_way <= unsigned(plru_victim(to_integer(r1.store_index)));
|
||||
else
|
||||
replace_way <= r1.store_way;
|
||||
end if;
|
||||
|
||||
-- See if the request matches the line currently being reloaded
|
||||
if r1.state = RELOAD_WAIT_ACK and req_index = r1.store_index and
|
||||
rel_match = '1' then
|
||||
if r1.state = RELOAD_WAIT_ACK and rel_match = '1' then
|
||||
assert not is_X(rindex);
|
||||
assert not is_X(r1.store_index);
|
||||
end if;
|
||||
if r1.state = RELOAD_WAIT_ACK and rel_match = '1' and
|
||||
rindex = r1.store_index then
|
||||
-- Ignore is_hit from above, because a load miss writes the new tag
|
||||
-- but doesn't clear the valid bit on the line before refilling it.
|
||||
-- For a store, consider this a hit even if the row isn't valid
|
||||
-- since it will be by the time we perform the store.
|
||||
-- For a load, check the appropriate row valid bit; but also,
|
||||
-- if use_forward_rl is 1 then we can consider this a hit.
|
||||
is_hit := not r0.req.load or r1.rows_valid(req_row mod ROW_PER_LINE) or
|
||||
is_hit := not r0.req.load or r1.rows_valid(to_integer(req_row(ROW_LINEBITS-1 downto 0))) or
|
||||
use_forward_rl;
|
||||
hit_way := replace_way;
|
||||
end if;
|
||||
@@ -982,11 +1044,14 @@ begin
|
||||
if r0_stall = '0' then
|
||||
if m_in.valid = '1' then
|
||||
early_req_row <= get_row(m_in.addr);
|
||||
early_rd_valid <= not (m_in.tlbie or m_in.tlbld);
|
||||
else
|
||||
early_req_row <= get_row(d_in.addr);
|
||||
early_rd_valid <= d_in.valid and d_in.load;
|
||||
end if;
|
||||
else
|
||||
early_req_row <= req_row;
|
||||
early_rd_valid <= r0.req.valid and r0.req.load;
|
||||
end if;
|
||||
end process;
|
||||
|
||||
@@ -1145,8 +1210,8 @@ begin
|
||||
process(all)
|
||||
begin
|
||||
-- Cache hit reads
|
||||
do_read <= '1';
|
||||
rd_addr <= std_ulogic_vector(to_unsigned(early_req_row, ROW_BITS));
|
||||
do_read <= early_rd_valid;
|
||||
rd_addr <= std_ulogic_vector(early_req_row);
|
||||
cache_out(i) <= dout;
|
||||
|
||||
-- Write mux:
|
||||
@@ -1156,13 +1221,15 @@ begin
|
||||
-- For timing, the mux on wr_data/sel/addr is not dependent on anything
|
||||
-- other than the current state.
|
||||
--
|
||||
wr_addr <= std_ulogic_vector(to_unsigned(r1.store_row, ROW_BITS));
|
||||
wr_addr <= std_ulogic_vector(r1.store_row);
|
||||
|
||||
wr_sel_m <= (others => '0');
|
||||
if i = replace_way and
|
||||
(r1.write_bram = '1' or
|
||||
(r1.state = RELOAD_WAIT_ACK and wishbone_in.ack = '1')) then
|
||||
wr_sel_m <= ram_wr_select;
|
||||
if r1.write_bram = '1' or
|
||||
(r1.state = RELOAD_WAIT_ACK and wishbone_in.ack = '1') then
|
||||
assert not is_X(replace_way);
|
||||
if to_unsigned(i, WAY_BITS) = replace_way then
|
||||
wr_sel_m <= ram_wr_select;
|
||||
end if;
|
||||
end if;
|
||||
|
||||
end process;
|
||||
@@ -1182,9 +1249,9 @@ begin
|
||||
report "op:" & op_t'image(req_op) &
|
||||
" addr:" & to_hstring(r0.req.addr) &
|
||||
" nc:" & std_ulogic'image(r0.req.nc) &
|
||||
" idx:" & integer'image(req_index) &
|
||||
" idx:" & to_hstring(req_index) &
|
||||
" tag:" & to_hstring(req_tag) &
|
||||
" way: " & integer'image(req_hit_way);
|
||||
" way: " & to_hstring(req_hit_way);
|
||||
end if;
|
||||
if r0_valid = '1' then
|
||||
r1.mmu_req <= r0.mmu_req;
|
||||
@@ -1213,7 +1280,11 @@ begin
|
||||
when "10" =>
|
||||
data_out(j + 7 downto j) := r1.forward_data(j + 7 downto j);
|
||||
when others =>
|
||||
data_out(j + 7 downto j) := cache_out(req_hit_way)(j + 7 downto j);
|
||||
if is_X(req_hit_way) then
|
||||
data_out(j + 7 downto j) := (others => 'X');
|
||||
else
|
||||
data_out(j + 7 downto j) := cache_out(to_integer(req_hit_way))(j + 7 downto j);
|
||||
end if;
|
||||
end case;
|
||||
end loop;
|
||||
r1.data_out <= data_out;
|
||||
@@ -1290,7 +1361,7 @@ begin
|
||||
|
||||
-- On reset, clear all valid bits to force misses
|
||||
if rst = '1' then
|
||||
for i in index_t loop
|
||||
for i in 0 to NUM_LINES-1 loop
|
||||
cache_valids(i) <= (others => '0');
|
||||
end loop;
|
||||
r1.state <= IDLE;
|
||||
@@ -1322,17 +1393,24 @@ begin
|
||||
end if;
|
||||
|
||||
-- Do invalidations from snooped stores to memory
|
||||
for i in way_t loop
|
||||
if snoop_valid = '1' then
|
||||
assert not is_X(snoop_tag_set);
|
||||
assert not is_X(snoop_wrtag);
|
||||
end if;
|
||||
for i in 0 to NUM_WAYS-1 loop
|
||||
if snoop_valid = '1' and read_tag(i, snoop_tag_set) = snoop_wrtag then
|
||||
cache_valids(snoop_index)(i) <= '0';
|
||||
assert not is_X(snoop_index);
|
||||
cache_valids(to_integer(snoop_index))(i) <= '0';
|
||||
end if;
|
||||
end loop;
|
||||
|
||||
if r1.write_tag = '1' then
|
||||
-- Store new tag in selected way
|
||||
assert not is_X(r1.store_index);
|
||||
assert not is_X(replace_way);
|
||||
for i in 0 to NUM_WAYS-1 loop
|
||||
if i = replace_way then
|
||||
cache_tags(r1.store_index)((i + 1) * TAG_WIDTH - 1 downto i * TAG_WIDTH) <=
|
||||
if to_unsigned(i, WAY_BITS) = replace_way then
|
||||
cache_tags(to_integer(r1.store_index))((i + 1) * TAG_WIDTH - 1 downto i * TAG_WIDTH) <=
|
||||
(TAG_WIDTH - 1 downto TAG_BITS => '0') & r1.reload_tag;
|
||||
end if;
|
||||
end loop;
|
||||
@@ -1408,7 +1486,7 @@ begin
|
||||
-- Normal load cache miss, start the reload machine
|
||||
--
|
||||
report "cache miss real addr:" & to_hstring(req.real_addr) &
|
||||
" idx:" & integer'image(get_index(req.real_addr)) &
|
||||
" idx:" & to_hstring(get_index(req.real_addr)) &
|
||||
" tag:" & to_hstring(get_tag(req.real_addr));
|
||||
|
||||
-- Start the wishbone cycle
|
||||
@@ -1467,6 +1545,8 @@ begin
|
||||
-- If we are still sending requests, was one accepted ?
|
||||
if wishbone_in.stall = '0' and r1.wb.stb = '1' then
|
||||
-- That was the last word ? We are done sending. Clear stb.
|
||||
assert not is_X(r1.wb.adr);
|
||||
assert not is_X(r1.end_row_ix);
|
||||
if is_last_row_wb_addr(r1.wb.adr, r1.end_row_ix) then
|
||||
r1.wb.stb <= '0';
|
||||
end if;
|
||||
@@ -1477,13 +1557,17 @@ begin
|
||||
|
||||
-- Incoming acks processing
|
||||
if wishbone_in.ack = '1' then
|
||||
r1.rows_valid(r1.store_row mod ROW_PER_LINE) <= '1';
|
||||
r1.rows_valid(to_integer(r1.store_row(ROW_LINEBITS-1 downto 0))) <= '1';
|
||||
-- If this is the data we were looking for, we can
|
||||
-- complete the request next cycle.
|
||||
-- Compare the whole address in case the request in
|
||||
-- r1.req is not the one that started this refill.
|
||||
-- (Cases where req comes from r0 are handled as a load
|
||||
-- hit.)
|
||||
if r1.full = '1' then
|
||||
assert not is_X(r1.store_row);
|
||||
assert not is_X(r1.req.real_addr);
|
||||
end if;
|
||||
if r1.full = '1' and r1.req.same_tag = '1' and
|
||||
((r1.dcbz = '1' and req.dcbz = '1') or r1.req.op = OP_LOAD_MISS) and
|
||||
r1.store_row = get_row(r1.req.real_addr) then
|
||||
@@ -1497,12 +1581,16 @@ begin
|
||||
end if;
|
||||
|
||||
-- Check for completion
|
||||
assert not is_X(r1.store_row);
|
||||
assert not is_X(r1.end_row_ix);
|
||||
if is_last_row(r1.store_row, r1.end_row_ix) then
|
||||
-- Complete wishbone cycle
|
||||
r1.wb.cyc <= '0';
|
||||
|
||||
-- Cache line is now valid
|
||||
cache_valids(r1.store_index)(r1.store_way) <= '1';
|
||||
assert not is_X(r1.store_index);
|
||||
assert not is_X(r1.store_way);
|
||||
cache_valids(to_integer(r1.store_index))(to_integer(r1.store_way)) <= '1';
|
||||
|
||||
ev.dcache_refill <= not r1.dcbz;
|
||||
r1.state <= IDLE;
|
||||
@@ -1533,6 +1621,7 @@ begin
|
||||
r1.wb.dat <= req.data;
|
||||
r1.wb.sel <= req.byte_sel;
|
||||
end if;
|
||||
assert not is_X(acks);
|
||||
if acks < 7 and req.same_tag = '1' and req.dcbz = '0' and
|
||||
(req.op = OP_STORE_MISS or req.op = OP_STORE_HIT) then
|
||||
r1.wb.stb <= '1';
|
||||
@@ -1556,6 +1645,7 @@ begin
|
||||
|
||||
-- Got ack ? See if complete.
|
||||
if wishbone_in.ack = '1' then
|
||||
assert not is_X(acks);
|
||||
if stbs_done and acks = 1 then
|
||||
r1.state <= IDLE;
|
||||
r1.wb.cyc <= '0';
|
||||
@@ -1602,7 +1692,7 @@ begin
|
||||
d_out.valid &
|
||||
std_ulogic_vector(to_unsigned(op_t'pos(req_op), 3)) &
|
||||
stall_out &
|
||||
std_ulogic_vector(to_unsigned(tlb_hit_way, 3)) &
|
||||
std_ulogic_vector(resize(tlb_hit_way, 3)) &
|
||||
valid_ra &
|
||||
std_ulogic_vector(to_unsigned(state_t'pos(r1.state), 3));
|
||||
end if;
|
||||
|
||||
50
decode2.vhdl
50
decode2.vhdl
@@ -434,27 +434,37 @@ begin
|
||||
v.input_ov := '1'; -- need SO state if setting OV to 0
|
||||
end if;
|
||||
when OP_MFSPR =>
|
||||
case decode_spr_num(d_in.insn) is
|
||||
when SPR_XER =>
|
||||
v.input_ov := '1';
|
||||
when SPR_DAR | SPR_DSISR | SPR_PID | SPR_PTCR =>
|
||||
unit := LDST;
|
||||
when others =>
|
||||
end case;
|
||||
if is_X(d_in.insn) then
|
||||
v.input_ov := 'X';
|
||||
else
|
||||
case decode_spr_num(d_in.insn) is
|
||||
when SPR_XER =>
|
||||
v.input_ov := '1';
|
||||
when SPR_DAR | SPR_DSISR | SPR_PID | SPR_PTCR =>
|
||||
unit := LDST;
|
||||
when others =>
|
||||
end case;
|
||||
end if;
|
||||
when OP_MTSPR =>
|
||||
case decode_spr_num(d_in.insn) is
|
||||
when SPR_XER =>
|
||||
v.e.output_xer := '1';
|
||||
v.output_ov := '1';
|
||||
when SPR_DAR | SPR_DSISR | SPR_PID | SPR_PTCR =>
|
||||
unit := LDST;
|
||||
if d_in.valid = '1' then
|
||||
v.sgl_pipe := '1';
|
||||
end if;
|
||||
when others =>
|
||||
end case;
|
||||
if d_in.spr_info.valid = '1' and d_in.valid = '1' then
|
||||
v.sgl_pipe := '1';
|
||||
if is_X(d_in.insn) then
|
||||
v.e.output_xer := 'X';
|
||||
v.output_ov := 'X';
|
||||
v.sgl_pipe := 'X';
|
||||
else
|
||||
case decode_spr_num(d_in.insn) is
|
||||
when SPR_XER =>
|
||||
v.e.output_xer := '1';
|
||||
v.output_ov := '1';
|
||||
when SPR_DAR | SPR_DSISR | SPR_PID | SPR_PTCR =>
|
||||
unit := LDST;
|
||||
if d_in.valid = '1' then
|
||||
v.sgl_pipe := '1';
|
||||
end if;
|
||||
when others =>
|
||||
end case;
|
||||
if d_in.spr_info.valid = '1' and d_in.valid = '1' then
|
||||
v.sgl_pipe := '1';
|
||||
end if;
|
||||
end if;
|
||||
when OP_CMP | OP_MCRXRX =>
|
||||
v.input_ov := '1';
|
||||
|
||||
@@ -863,11 +863,16 @@ begin
|
||||
else
|
||||
a_lt_lo := '0';
|
||||
a_lt_hi := '0';
|
||||
if unsigned(a_in(30 downto 0)) < unsigned(b_in(30 downto 0)) then
|
||||
a_lt_lo := '1';
|
||||
end if;
|
||||
if unsigned(a_in(62 downto 31)) < unsigned(b_in(62 downto 31)) then
|
||||
a_lt_hi := '1';
|
||||
if is_X(a_in) or is_X(b_in) then
|
||||
a_lt_lo := 'X';
|
||||
a_lt_hi := 'X';
|
||||
else
|
||||
if unsigned(a_in(30 downto 0)) < unsigned(b_in(30 downto 0)) then
|
||||
a_lt_lo := '1';
|
||||
end if;
|
||||
if unsigned(a_in(62 downto 31)) < unsigned(b_in(62 downto 31)) then
|
||||
a_lt_hi := '1';
|
||||
end if;
|
||||
end if;
|
||||
if l = '1' then
|
||||
-- 64-bit comparison
|
||||
@@ -893,7 +898,6 @@ begin
|
||||
|
||||
-- CR result mux
|
||||
bf := insn_bf(e_in.insn);
|
||||
crnum := to_integer(unsigned(bf));
|
||||
newcrf := (others => '0');
|
||||
case e_in.sub_select is
|
||||
when "000" =>
|
||||
@@ -908,8 +912,11 @@ begin
|
||||
when "010" =>
|
||||
newcrf := ppc_cmpeqb(a_in, b_in);
|
||||
when "011" =>
|
||||
if e_in.insn(1) = '1' then
|
||||
if is_X(e_in.insn) then
|
||||
newcrf := (others => 'X');
|
||||
elsif e_in.insn(1) = '1' then
|
||||
-- CR logical instructions
|
||||
crnum := to_integer(unsigned(bf));
|
||||
j := (7 - crnum) * 4;
|
||||
newcrf := cr_in(j + 3 downto j);
|
||||
bt := insn_bt(e_in.insn);
|
||||
@@ -948,7 +955,8 @@ begin
|
||||
crnum := fxm_to_num(insn_fxm(e_in.insn));
|
||||
write_cr_mask <= num_to_fxm(crnum);
|
||||
end if;
|
||||
elsif e_in.output_cr = '1' then
|
||||
elsif e_in.output_cr = '1' and not is_X(bf) then
|
||||
crnum := to_integer(unsigned(bf));
|
||||
write_cr_mask <= num_to_fxm(crnum);
|
||||
else
|
||||
write_cr_mask <= (others => '0');
|
||||
|
||||
156
icache.vhdl
156
icache.vhdl
@@ -4,9 +4,7 @@
|
||||
-- TODO (in no specific order):
|
||||
--
|
||||
-- * Add debug interface to inspect cache content
|
||||
-- * Add snoop/invalidate path
|
||||
-- * Add multi-hit error detection
|
||||
-- * Pipelined bus interface (wb or axi)
|
||||
-- * Maybe add parity ? There's a few bits free in each BRAM row on Xilinx
|
||||
-- * Add optimization: service hits on partially loaded lines
|
||||
-- * Add optimization: (maybe) interrupt reload on fluch/redirect
|
||||
@@ -119,9 +117,11 @@ architecture rtl of icache is
|
||||
-- .. |-----| | INDEX_BITS (5)
|
||||
-- .. --------| | TAG_BITS (53)
|
||||
|
||||
subtype row_t is integer range 0 to BRAM_ROWS-1;
|
||||
subtype row_t is unsigned(ROW_BITS-1 downto 0);
|
||||
subtype index_t is integer range 0 to NUM_LINES-1;
|
||||
subtype index_sig_t is unsigned(INDEX_BITS-1 downto 0);
|
||||
subtype way_t is integer range 0 to NUM_WAYS-1;
|
||||
subtype way_sig_t is unsigned(WAY_BITS-1 downto 0);
|
||||
subtype row_in_line_t is unsigned(ROW_LINEBITS-1 downto 0);
|
||||
|
||||
-- We store a pre-decoded 10-bit insn_code along with the bottom 26 bits of
|
||||
@@ -187,7 +187,7 @@ architecture rtl of icache is
|
||||
|
||||
type reg_internal_t is record
|
||||
-- Cache hit state (Latches for 1 cycle BRAM access)
|
||||
hit_way : way_t;
|
||||
hit_way : way_sig_t;
|
||||
hit_nia : std_ulogic_vector(63 downto 0);
|
||||
hit_smark : std_ulogic;
|
||||
hit_valid : std_ulogic;
|
||||
@@ -196,8 +196,8 @@ architecture rtl of icache is
|
||||
-- Cache miss state (reload state machine)
|
||||
state : state_t;
|
||||
wb : wishbone_master_out;
|
||||
store_way : way_t;
|
||||
store_index : index_t;
|
||||
store_way : way_sig_t;
|
||||
store_index : index_sig_t;
|
||||
recv_row : row_t;
|
||||
recv_valid : std_ulogic;
|
||||
store_row : row_t;
|
||||
@@ -215,9 +215,9 @@ architecture rtl of icache is
|
||||
signal ev : IcacheEventType;
|
||||
|
||||
-- Async signals on incoming request
|
||||
signal req_index : index_t;
|
||||
signal req_index : index_sig_t;
|
||||
signal req_row : row_t;
|
||||
signal req_hit_way : way_t;
|
||||
signal req_hit_way : way_sig_t;
|
||||
signal req_tag : cache_tag_t;
|
||||
signal req_is_hit : std_ulogic;
|
||||
signal req_is_miss : std_ulogic;
|
||||
@@ -237,33 +237,30 @@ architecture rtl of icache is
|
||||
-- PLRU output interface
|
||||
type plru_out_t is array(index_t) of std_ulogic_vector(WAY_BITS-1 downto 0);
|
||||
signal plru_victim : plru_out_t;
|
||||
signal replace_way : way_t;
|
||||
|
||||
-- Memory write snoop signals
|
||||
signal snoop_valid : std_ulogic;
|
||||
signal snoop_index : index_t;
|
||||
signal snoop_index : index_sig_t;
|
||||
signal snoop_hits : cache_way_valids_t;
|
||||
|
||||
signal log_insn : std_ulogic_vector(35 downto 0);
|
||||
|
||||
-- Return the cache line index (tag index) for an address
|
||||
function get_index(addr: std_ulogic_vector) return index_t is
|
||||
function get_index(addr: std_ulogic_vector) return index_sig_t is
|
||||
begin
|
||||
return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto LINE_OFF_BITS)));
|
||||
return 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) return row_t is
|
||||
begin
|
||||
return to_integer(unsigned(addr(SET_SIZE_BITS - 1 downto ROW_OFF_BITS)));
|
||||
return unsigned(addr(SET_SIZE_BITS - 1 downto ROW_OFF_BITS));
|
||||
end;
|
||||
|
||||
-- Return the index of a row within a line
|
||||
function get_row_of_line(row: row_t) return row_in_line_t is
|
||||
variable row_v : unsigned(ROW_BITS-1 downto 0);
|
||||
begin
|
||||
row_v := to_unsigned(row, ROW_BITS);
|
||||
return row_v(ROW_LINEBITS-1 downto 0);
|
||||
return row(ROW_LINEBITS-1 downto 0);
|
||||
end;
|
||||
|
||||
-- Returns whether this is the last row of a line
|
||||
@@ -298,13 +295,13 @@ architecture rtl of icache is
|
||||
--
|
||||
function next_row(row: row_t) return row_t is
|
||||
variable row_v : std_ulogic_vector(ROW_BITS-1 downto 0);
|
||||
variable row_idx : std_ulogic_vector(ROW_LINEBITS-1 downto 0);
|
||||
variable row_idx : unsigned(ROW_LINEBITS-1 downto 0);
|
||||
variable result : std_ulogic_vector(ROW_BITS-1 downto 0);
|
||||
begin
|
||||
row_v := std_ulogic_vector(to_unsigned(row, ROW_BITS));
|
||||
row_idx := row_v(ROW_LINEBITS-1 downto 0);
|
||||
row_v(ROW_LINEBITS-1 downto 0) := std_ulogic_vector(unsigned(row_idx) + 1);
|
||||
return to_integer(unsigned(row_v));
|
||||
row_v := std_ulogic_vector(row);
|
||||
row_idx := row(ROW_LINEBITS-1 downto 0);
|
||||
row_v(ROW_LINEBITS-1 downto 0) := std_ulogic_vector(row_idx + 1);
|
||||
return unsigned(row_v);
|
||||
end;
|
||||
|
||||
-- Read the instruction word for the given address in the current cache row
|
||||
@@ -312,6 +309,7 @@ architecture rtl of icache is
|
||||
data: cache_row_t) return std_ulogic_vector is
|
||||
variable word: integer range 0 to INSN_PER_ROW-1;
|
||||
begin
|
||||
assert not is_X(addr) severity failure;
|
||||
word := to_integer(unsigned(addr(INSN_BITS+2-1 downto 2)));
|
||||
return data(word * ICWORDLEN + ICWORDLEN - 1 downto word * ICWORDLEN);
|
||||
end;
|
||||
@@ -436,12 +434,12 @@ begin
|
||||
begin
|
||||
do_read <= not stall_in;
|
||||
do_write <= '0';
|
||||
if r.recv_valid = '1' and r.store_way = i then
|
||||
if r.recv_valid = '1' and r.store_way = to_unsigned(i, WAY_BITS) then
|
||||
do_write <= '1';
|
||||
end if;
|
||||
cache_out(i) <= dout;
|
||||
rd_addr <= std_ulogic_vector(to_unsigned(req_row, ROW_BITS));
|
||||
wr_addr <= std_ulogic_vector(to_unsigned(r.store_row, ROW_BITS));
|
||||
rd_addr <= std_ulogic_vector(req_row);
|
||||
wr_addr <= std_ulogic_vector(r.store_row);
|
||||
wr_sel(0) <= do_write;
|
||||
end process;
|
||||
end generate;
|
||||
@@ -478,7 +476,7 @@ begin
|
||||
else
|
||||
plru_acc_en <= '0';
|
||||
end if;
|
||||
plru_acc <= std_ulogic_vector(to_unsigned(r.hit_way, WAY_BITS));
|
||||
plru_acc <= std_ulogic_vector(r.hit_way);
|
||||
plru_victim(i) <= plru_out;
|
||||
end process;
|
||||
end generate;
|
||||
@@ -550,15 +548,13 @@ begin
|
||||
-- Cache hit detection, output to fetch2 and other misc logic
|
||||
icache_comb : process(all)
|
||||
variable is_hit : std_ulogic;
|
||||
variable hit_way : way_t;
|
||||
variable hit_way : way_sig_t;
|
||||
variable insn : std_ulogic_vector(ICWORDLEN - 1 downto 0);
|
||||
variable icode : insn_code;
|
||||
begin
|
||||
-- Extract line, row and tag from request
|
||||
if not is_X(i_in.nia) then
|
||||
req_index <= get_index(i_in.nia);
|
||||
req_row <= get_row(i_in.nia);
|
||||
end if;
|
||||
req_index <= get_index(i_in.nia);
|
||||
req_row <= get_row(i_in.nia);
|
||||
req_tag <= get_tag(real_addr, i_in.big_endian);
|
||||
|
||||
-- Calculate address of beginning of cache row, will be
|
||||
@@ -568,21 +564,20 @@ begin
|
||||
(ROW_OFF_BITS-1 downto 0 => '0');
|
||||
|
||||
-- Test if pending request is a hit on any way
|
||||
hit_way := 0;
|
||||
hit_way := to_unsigned(0, WAY_BITS);
|
||||
is_hit := '0';
|
||||
if i_in.req = '1' then
|
||||
assert not is_X(req_index) and not is_X(req_row) severity failure;
|
||||
end if;
|
||||
for i in way_t loop
|
||||
if is_X(i_in.nia) then
|
||||
-- FIXME: This is fragile
|
||||
-- req_index or req_row could be a metavalue
|
||||
is_hit := 'X';
|
||||
elsif i_in.req = '1' and
|
||||
(cache_valids(req_index)(i) = '1' or
|
||||
if i_in.req = '1' and
|
||||
(cache_valids(to_integer(req_index))(i) = '1' or
|
||||
(r.state = WAIT_ACK and
|
||||
req_index = r.store_index and
|
||||
i = r.store_way and
|
||||
r.rows_valid(req_row mod ROW_PER_LINE) = '1')) then
|
||||
if read_tag(i, cache_tags(req_index)) = req_tag then
|
||||
hit_way := i;
|
||||
to_unsigned(i, WAY_BITS) = r.store_way and
|
||||
r.rows_valid(to_integer(req_row(ROW_LINEBITS-1 downto 0))) = '1')) then
|
||||
if read_tag(i, cache_tags(to_integer(req_index))) = req_tag then
|
||||
hit_way := to_unsigned(i, WAY_BITS);
|
||||
is_hit := '1';
|
||||
end if;
|
||||
end if;
|
||||
@@ -598,13 +593,6 @@ begin
|
||||
end if;
|
||||
req_hit_way <= hit_way;
|
||||
|
||||
-- The way to replace on a miss
|
||||
if r.state = CLR_TAG then
|
||||
replace_way <= to_integer(unsigned(plru_victim(r.store_index)));
|
||||
else
|
||||
replace_way <= r.store_way;
|
||||
end if;
|
||||
|
||||
-- Output instruction from current cache row
|
||||
--
|
||||
-- Note: This is a mild violation of our design principle of having pipeline
|
||||
@@ -616,10 +604,13 @@ begin
|
||||
insn := (others => '0');
|
||||
icode := INSN_illegal;
|
||||
if r.hit_valid = '1' then
|
||||
insn := read_insn_word(r.hit_nia, cache_out(r.hit_way));
|
||||
assert not is_X(r.hit_way) severity failure;
|
||||
insn := read_insn_word(r.hit_nia, cache_out(to_integer(r.hit_way)));
|
||||
-- Currently we use only the top bit for indicating illegal
|
||||
-- instructions because we know that insn_codes fit into 9 bits.
|
||||
if insn(ICWORDLEN - 1) = '0' then
|
||||
if is_X(insn) then
|
||||
insn := (others => '0');
|
||||
elsif insn(ICWORDLEN - 1) = '0' then
|
||||
icode := insn_code'val(to_integer(unsigned(insn(ICWORDLEN-1 downto INSN_IMAGE_BITS))));
|
||||
end if;
|
||||
end if;
|
||||
@@ -664,9 +655,9 @@ begin
|
||||
report "cache hit nia:" & to_hstring(i_in.nia) &
|
||||
" IR:" & std_ulogic'image(i_in.virt_mode) &
|
||||
" SM:" & std_ulogic'image(i_in.stop_mark) &
|
||||
" idx:" & integer'image(req_index) &
|
||||
" idx:" & to_hstring(req_index) &
|
||||
" tag:" & to_hstring(req_tag) &
|
||||
" way:" & integer'image(req_hit_way) &
|
||||
" way:" & to_hstring(req_hit_way) &
|
||||
" RA:" & to_hstring(real_addr);
|
||||
end if;
|
||||
end if;
|
||||
@@ -676,6 +667,9 @@ begin
|
||||
r.hit_nia <= i_in.nia;
|
||||
r.big_endian <= i_in.big_endian;
|
||||
end if;
|
||||
if i_out.valid = '1' then
|
||||
assert not is_X(i_out.insn) severity failure;
|
||||
end if;
|
||||
end if;
|
||||
end process;
|
||||
|
||||
@@ -686,7 +680,7 @@ begin
|
||||
variable snoop_addr : real_addr_t;
|
||||
variable snoop_tag : cache_tag_t;
|
||||
variable snoop_cache_tags : cache_tags_set_t;
|
||||
variable replace_way : way_t;
|
||||
variable replace_way : way_sig_t;
|
||||
begin
|
||||
if rising_edge(clk) then
|
||||
ev.icache_miss <= '0';
|
||||
@@ -709,7 +703,7 @@ begin
|
||||
r.wb.adr <= (others => '0');
|
||||
|
||||
snoop_valid <= '0';
|
||||
snoop_index <= 0;
|
||||
snoop_index <= to_unsigned(0, INDEX_BITS);
|
||||
snoop_hits <= (others => '0');
|
||||
else
|
||||
-- Detect snooped writes and decode address into index and tag
|
||||
@@ -717,20 +711,22 @@ begin
|
||||
snoop_valid <= wb_snoop_in.cyc and wb_snoop_in.stb and wb_snoop_in.we;
|
||||
snoop_addr := addr_to_real(wb_to_addr(wb_snoop_in.adr));
|
||||
snoop_index <= get_index(snoop_addr);
|
||||
snoop_cache_tags := cache_tags(get_index(snoop_addr));
|
||||
if snoop_valid = '1' and is_X(snoop_addr) then
|
||||
report "metavalue in snoop_addr" severity FAILURE;
|
||||
end if;
|
||||
snoop_tag := get_tag(snoop_addr, '0');
|
||||
snoop_hits <= (others => '0');
|
||||
for i in way_t loop
|
||||
tag := read_tag(i, snoop_cache_tags);
|
||||
-- Ignore endian bit in comparison
|
||||
tag(TAG_BITS - 1) := '0';
|
||||
if tag = snoop_tag then
|
||||
snoop_hits(i) <= '1';
|
||||
if snoop_valid = '1' then
|
||||
if is_X(snoop_addr) then
|
||||
report "metavalue in snoop_addr" severity FAILURE;
|
||||
end if;
|
||||
end loop;
|
||||
snoop_cache_tags := cache_tags(to_integer(get_index(snoop_addr)));
|
||||
for i in way_t loop
|
||||
tag := read_tag(i, snoop_cache_tags);
|
||||
-- Ignore endian bit in comparison
|
||||
tag(TAG_BITS - 1) := '0';
|
||||
if tag = snoop_tag then
|
||||
snoop_hits(i) <= '1';
|
||||
end if;
|
||||
end loop;
|
||||
end if;
|
||||
|
||||
-- Process cache invalidations
|
||||
if inval_in = '1' then
|
||||
@@ -742,8 +738,9 @@ begin
|
||||
-- Do invalidations from snooped stores to memory, one
|
||||
-- cycle after the address appears on wb_snoop_in.
|
||||
for i in way_t loop
|
||||
if snoop_valid = '1' and snoop_hits(i) = '1' then
|
||||
cache_valids(snoop_index)(i) <= '0';
|
||||
if snoop_hits(i) = '1' then
|
||||
assert not is_X(snoop_index) severity failure;
|
||||
cache_valids(to_integer(snoop_index))(i) <= '0';
|
||||
end if;
|
||||
end loop;
|
||||
end if;
|
||||
@@ -761,7 +758,7 @@ begin
|
||||
report "cache miss nia:" & to_hstring(i_in.nia) &
|
||||
" IR:" & std_ulogic'image(i_in.virt_mode) &
|
||||
" SM:" & std_ulogic'image(i_in.stop_mark) &
|
||||
" idx:" & integer'image(req_index) &
|
||||
" idx:" & to_hstring(req_index) &
|
||||
" tag:" & to_hstring(req_tag) &
|
||||
" RA:" & to_hstring(real_addr);
|
||||
ev.icache_miss <= '1';
|
||||
@@ -786,20 +783,24 @@ begin
|
||||
end if;
|
||||
|
||||
when CLR_TAG | WAIT_ACK =>
|
||||
assert not is_X(r.store_index) severity failure;
|
||||
assert not is_X(r.store_row) severity failure;
|
||||
assert not is_X(r.recv_row) severity failure;
|
||||
if r.state = CLR_TAG then
|
||||
-- Get victim way from plru
|
||||
replace_way := to_integer(unsigned(plru_victim(r.store_index)));
|
||||
replace_way := unsigned(plru_victim(to_integer(r.store_index)));
|
||||
r.store_way <= replace_way;
|
||||
|
||||
-- Force misses on that way while reloading that line
|
||||
cache_valids(req_index)(replace_way) <= '0';
|
||||
assert not is_X(replace_way) severity failure;
|
||||
cache_valids(to_integer(r.store_index))(to_integer(replace_way)) <= '0';
|
||||
|
||||
-- Store new tag in selected way
|
||||
for i in 0 to NUM_WAYS-1 loop
|
||||
if i = replace_way then
|
||||
tagset := cache_tags(r.store_index);
|
||||
if to_unsigned(i, WAY_BITS) = replace_way then
|
||||
tagset := cache_tags(to_integer(r.store_index));
|
||||
write_tag(i, tagset, r.store_tag);
|
||||
cache_tags(r.store_index) <= tagset;
|
||||
cache_tags(to_integer(r.store_index)) <= tagset;
|
||||
end if;
|
||||
end loop;
|
||||
|
||||
@@ -808,10 +809,11 @@ begin
|
||||
|
||||
-- If we are writing in this cycle, mark row valid and see if we are done
|
||||
if r.recv_valid = '1' then
|
||||
r.rows_valid(r.store_row mod ROW_PER_LINE) <= not inval_in;
|
||||
r.rows_valid(to_integer(r.store_row(ROW_LINEBITS-1 downto 0))) <= not inval_in;
|
||||
if is_last_row(r.store_row, r.end_row_ix) then
|
||||
-- Cache line is now valid
|
||||
cache_valids(r.store_index)(r.store_way) <= r.store_valid and not inval_in;
|
||||
cache_valids(to_integer(r.store_index))(to_integer(r.store_way)) <=
|
||||
r.store_valid and not inval_in;
|
||||
-- We are done
|
||||
r.state <= IDLE;
|
||||
end if;
|
||||
@@ -878,7 +880,7 @@ begin
|
||||
signal log_data : std_ulogic_vector(57 downto 0);
|
||||
begin
|
||||
data_log: process(clk)
|
||||
variable lway: way_t;
|
||||
variable lway: way_sig_t;
|
||||
variable wstate: std_ulogic;
|
||||
begin
|
||||
if rising_edge(clk) then
|
||||
@@ -897,7 +899,7 @@ begin
|
||||
r.fetch_failed &
|
||||
r.hit_nia(5 downto 2) &
|
||||
wstate &
|
||||
std_ulogic_vector(to_unsigned(lway, 3)) &
|
||||
std_ulogic_vector(resize(lway, 3)) &
|
||||
req_is_hit & req_is_miss &
|
||||
access_ok &
|
||||
ra_valid;
|
||||
|
||||
@@ -199,9 +199,14 @@ architecture behave of loadstore1 is
|
||||
return std_ulogic_vector is
|
||||
variable longsel : std_ulogic_vector(15 downto 0);
|
||||
begin
|
||||
longsel := "00000000" & length_to_sel(size);
|
||||
return std_ulogic_vector(shift_left(unsigned(longsel),
|
||||
to_integer(unsigned(address))));
|
||||
if is_X(address) then
|
||||
longsel := (others => 'X');
|
||||
return longsel;
|
||||
else
|
||||
longsel := "00000000" & length_to_sel(size);
|
||||
return std_ulogic_vector(shift_left(unsigned(longsel),
|
||||
to_integer(unsigned(address))));
|
||||
end if;
|
||||
end function xfer_data_sel;
|
||||
|
||||
-- 23-bit right shifter for DP -> SP float conversions
|
||||
@@ -401,7 +406,7 @@ begin
|
||||
variable addr_mask : std_ulogic_vector(2 downto 0);
|
||||
begin
|
||||
v := request_init;
|
||||
sprn := std_ulogic_vector(to_unsigned(decode_spr_num(l_in.insn), 10));
|
||||
sprn := l_in.insn(15 downto 11) & l_in.insn(20 downto 16);
|
||||
|
||||
v.valid := l_in.valid;
|
||||
v.instr_tag := l_in.instr_tag;
|
||||
|
||||
Reference in New Issue
Block a user