use ieee.numeric_std.all;
library work;
+use work.utils.all;
use work.common.all;
entity core_debug is
+ generic (
+ -- Length of log buffer
+ LOG_LENGTH : natural := 512
+ );
port (
clk : in std_logic;
rst : in std_logic;
dbg_gpr_addr : out gspr_index_t;
dbg_gpr_data : in std_ulogic_vector(63 downto 0);
+ -- Core logging data
+ log_data : in std_ulogic_vector(255 downto 0);
+ log_read_addr : in std_ulogic_vector(31 downto 0);
+ log_read_data : out std_ulogic_vector(63 downto 0);
+ log_write_addr : out std_ulogic_vector(31 downto 0);
+
-- Misc
terminated_out : out std_ulogic
);
-- GSPR register data
constant DBG_CORE_GSPR_DATA : std_ulogic_vector(3 downto 0) := "0101";
+ -- Log buffer address and data registers
+ constant DBG_CORE_LOG_ADDR : std_ulogic_vector(3 downto 0) := "0110";
+ constant DBG_CORE_LOG_DATA : std_ulogic_vector(3 downto 0) := "0111";
+ constant DBG_CORE_LOG_TRIGGER : std_ulogic_vector(3 downto 0) := "1000";
+
+ constant LOG_INDEX_BITS : natural := log2(LOG_LENGTH);
+
-- Some internal wires
signal stat_reg : std_ulogic_vector(63 downto 0);
signal do_gspr_rd : std_ulogic;
signal gspr_index : gspr_index_t;
+ signal log_dmi_addr : std_ulogic_vector(31 downto 0) := (others => '0');
+ signal log_dmi_data : std_ulogic_vector(63 downto 0) := (others => '0');
+ signal log_dmi_trigger : std_ulogic_vector(63 downto 0) := (others => '0');
+ signal do_log_trigger : std_ulogic := '0';
+ signal do_dmi_log_rd : std_ulogic;
+ signal dmi_read_log_data : std_ulogic;
+ signal dmi_read_log_data_1 : std_ulogic;
+ signal log_trigger_delay : integer range 0 to 255 := 0;
+
begin
-- Single cycle register accesses on DMI except for GSPR data
dmi_ack <= dmi_req when dmi_addr /= DBG_CORE_GSPR_DATA
nia when DBG_CORE_NIA,
msr when DBG_CORE_MSR,
dbg_gpr_data when DBG_CORE_GSPR_DATA,
+ log_write_addr & log_dmi_addr when DBG_CORE_LOG_ADDR,
+ log_dmi_data when DBG_CORE_LOG_DATA,
+ log_dmi_trigger when DBG_CORE_LOG_TRIGGER,
(others => '0') when others;
-- DMI writes
do_step <= '0';
do_reset <= '0';
do_icreset <= '0';
+ do_dmi_log_rd <= '0';
if (rst) then
stopping <= '0';
terminated <= '0';
+ log_trigger_delay <= 0;
else
+ if do_log_trigger = '1' or log_trigger_delay /= 0 then
+ if log_trigger_delay = 255 then
+ log_dmi_trigger(1) <= '1';
+ log_trigger_delay <= 0;
+ else
+ log_trigger_delay <= log_trigger_delay + 1;
+ end if;
+ end if;
-- Edge detect on dmi_req for 1-shot pulses
dmi_req_1 <= dmi_req;
if dmi_req = '1' and dmi_req_1 = '0' then
end if;
elsif dmi_addr = DBG_CORE_GSPR_INDEX then
gspr_index <= dmi_din(gspr_index_t'left downto 0);
+ elsif dmi_addr = DBG_CORE_LOG_ADDR then
+ log_dmi_addr <= dmi_din(31 downto 0);
+ do_dmi_log_rd <= '1';
+ elsif dmi_addr = DBG_CORE_LOG_TRIGGER then
+ log_dmi_trigger <= dmi_din;
end if;
else
report("DMI read from " & to_string(dmi_addr));
end if;
+
+ elsif dmi_read_log_data = '0' and dmi_read_log_data_1 = '1' then
+ -- Increment log_dmi_addr after the end of a read from DBG_CORE_LOG_DATA
+ log_dmi_addr(LOG_INDEX_BITS + 1 downto 0) <=
+ std_ulogic_vector(unsigned(log_dmi_addr(LOG_INDEX_BITS+1 downto 0)) + 1);
+ do_dmi_log_rd <= '1';
end if;
+ dmi_read_log_data_1 <= dmi_read_log_data;
+ if dmi_req = '1' and dmi_addr = DBG_CORE_LOG_DATA then
+ dmi_read_log_data <= '1';
+ else
+ dmi_read_log_data <= '0';
+ end if;
-- Set core stop on terminate. We'll be stopping some time *after*
-- the offending instruction, at least until we can do back flushes
core_rst <= do_reset;
icache_rst <= do_icreset;
terminated_out <= terminated;
+
+ -- Logging RAM
+ maybe_log: if LOG_LENGTH > 0 generate
+ subtype log_ptr_t is unsigned(LOG_INDEX_BITS - 1 downto 0);
+ type log_array_t is array(0 to LOG_LENGTH - 1) of std_ulogic_vector(255 downto 0);
+ signal log_array : log_array_t;
+ signal log_rd_ptr : log_ptr_t;
+ signal log_wr_ptr : log_ptr_t;
+ signal log_toggle : std_ulogic;
+ signal log_wr_enable : std_ulogic;
+ signal log_rd_ptr_latched : log_ptr_t;
+ signal log_rd : std_ulogic_vector(255 downto 0);
+ signal log_dmi_reading : std_ulogic;
+ signal log_dmi_read_done : std_ulogic;
+
+ function select_dword(data : std_ulogic_vector(255 downto 0);
+ addr : std_ulogic_vector(31 downto 0)) return std_ulogic_vector is
+ variable firstbit : integer;
+ begin
+ firstbit := to_integer(unsigned(addr(1 downto 0))) * 64;
+ return data(firstbit + 63 downto firstbit);
+ end;
+
+ attribute ram_style : string;
+ attribute ram_style of log_array : signal is "block";
+ attribute ram_decomp : string;
+ attribute ram_decomp of log_array : signal is "power";
+
+ begin
+ -- Use MSB of read addresses to stop the logging
+ log_wr_enable <= not (log_read_addr(31) or log_dmi_addr(31) or log_dmi_trigger(1));
+
+ log_ram: process(clk)
+ begin
+ if rising_edge(clk) then
+ if log_wr_enable = '1' then
+ log_array(to_integer(log_wr_ptr)) <= log_data;
+ end if;
+ log_rd <= log_array(to_integer(log_rd_ptr_latched));
+ end if;
+ end process;
+
+
+ log_buffer: process(clk)
+ variable b : integer;
+ variable data : std_ulogic_vector(255 downto 0);
+ begin
+ if rising_edge(clk) then
+ if rst = '1' then
+ log_wr_ptr <= (others => '0');
+ log_toggle <= '0';
+ elsif log_wr_enable = '1' then
+ if log_wr_ptr = to_unsigned(LOG_LENGTH - 1, LOG_INDEX_BITS) then
+ log_toggle <= not log_toggle;
+ end if;
+ log_wr_ptr <= log_wr_ptr + 1;
+ end if;
+ if do_dmi_log_rd = '1' then
+ log_rd_ptr_latched <= unsigned(log_dmi_addr(LOG_INDEX_BITS + 1 downto 2));
+ else
+ log_rd_ptr_latched <= unsigned(log_read_addr(LOG_INDEX_BITS + 1 downto 2));
+ end if;
+ if log_dmi_read_done = '1' then
+ log_dmi_data <= select_dword(log_rd, log_dmi_addr);
+ else
+ log_read_data <= select_dword(log_rd, log_read_addr);
+ end if;
+ log_dmi_read_done <= log_dmi_reading;
+ log_dmi_reading <= do_dmi_log_rd;
+ do_log_trigger <= '0';
+ if log_data(42) = log_dmi_trigger(63) and
+ log_data(41 downto 0) = log_dmi_trigger(43 downto 2) and
+ log_dmi_trigger(0) = '1' then
+ do_log_trigger <= '1';
+ end if;
+ end if;
+ end process;
+ log_write_addr(LOG_INDEX_BITS - 1 downto 0) <= std_ulogic_vector(log_wr_ptr);
+ log_write_addr(LOG_INDEX_BITS) <= '1';
+ log_write_addr(31 downto LOG_INDEX_BITS + 1) <= (others => '0');
+ end generate;
+
+ no_log: if LOG_LENGTH = 0 generate
+ begin
+ log_read_data <= (others => '0');
+ log_write_addr <= x"00000001";
+ end generate;
+
end behave;