Remove some FPGA style signal inits

These don't work on the ASIC flow, so remove them and initialise
them explicitly where required.

Signed-off-by: Anton Blanchard <anton@linux.ibm.com>

spi_flash_ctrl.vhdl

@@ -58,7 +58,7 @@ architecture rtl of spi_flash_ctrl is
     alias  ctrl_div    : std_ulogic_vector(7 downto 0) is ctrl_reg(15 downto 8);
 
     -- Auto mode config register
-    signal auto_cfg_reg     : std_ulogic_vector(29 downto 0) := (others => '0');
+    signal auto_cfg_reg     : std_ulogic_vector(29 downto 0);
     alias  auto_cfg_cmd     : std_ulogic_vector(7 downto 0) is auto_cfg_reg(7 downto 0);
     alias  auto_cfg_dummies : std_ulogic_vector(2 downto 0) is auto_cfg_reg(10 downto 8);
     alias  auto_cfg_mode    : std_ulogic_vector(1 downto 0) is auto_cfg_reg(12 downto 11);
@@ -126,9 +126,9 @@ architecture rtl of spi_flash_ctrl is
     signal auto_latch_adr : std_ulogic;
 
     -- Automatic mode latches
-    signal auto_data      : std_ulogic_vector(wb_out.dat'left downto 0) := (others => '0');
+    signal auto_data      : std_ulogic_vector(wb_out.dat'left downto 0);
-    signal auto_cnt       : integer range 0 to 63 := 0;
+    signal auto_cnt       : integer range 0 to 63;
-    signal auto_state     : auto_state_t := AUTO_BOOT;
+    signal auto_state     : auto_state_t;
     signal auto_last_addr : std_ulogic_vector(31 downto 0);
 
 begin
@@ -351,6 +351,8 @@ begin
             if rst = '1' then
                 auto_last_addr <= (others => '0');
                 auto_state <= AUTO_BOOT;
+                auto_cnt <= 0;
+                auto_data  <= (others => '0');
             else
                 auto_state <= auto_next;
                 auto_cnt   <= auto_cnt_next;

spi_rxtx.vhdl

@@ -126,10 +126,10 @@ architecture rtl of spi_rxtx is
     signal dat_ack_l : std_ulogic;
 
     -- Delayed recv signal for the read machine
-    signal sck_recv_d : std_ulogic := '0';
+    signal sck_recv_d : std_ulogic;
 
     -- Input shift register (use fifo ?)
-    signal ireg       : std_ulogic_vector(7 downto 0) := (others => '0');
+    signal ireg       : std_ulogic_vector(7 downto 0);
 
     -- Bit counter
     signal bit_count  : std_ulogic_vector(2 downto 0);
@@ -157,7 +157,7 @@ architecture rtl of spi_rxtx is
     end;
 
     type state_t is (STANDBY, DATA);
-    signal state : state_t := STANDBY;
+    signal state : state_t;
 begin
 
     -- We don't support multiple data lines at this point
@@ -349,6 +349,9 @@ begin
     shift_in: process(clk)
     begin
         if rising_edge(clk) then
+            if rst = '1' then
+                ireg <= (others => '0');
+            end if;
 
             -- Delay the receive signal to match the input latch
             if state = DATA then