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minor edits

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stnolting 2020-09-14 22:03:29 +02:00
parent 8bb4757769
commit cd848850d8
1 changed files with 8 additions and 4 deletions
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12
rtl/core/neorv32_boot_rom.vhd
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@ -41,6 +41,10 @@ use neorv32.neorv32_package.all;
use neorv32.neorv32_bootloader_image.all; -- this file is generated by the image generator
entity neorv32_boot_rom is
generic (
BOOTROM_BASE : std_ulogic_vector(31 downto 0) := x"FFFF0000"; -- boot ROM base address
BOOTROM_SIZE : natural := 4*1024 -- processor-internal boot ROM memory size in bytes
);
port (
clk_i : in std_ulogic; -- global clock line
rden_i : in std_ulogic; -- read enable
@ -53,7 +57,7 @@ end neorv32_boot_rom;
architecture neorv32_boot_rom_rtl of neorv32_boot_rom is
-- local types --
type boot_img_t is array (0 to boot_size_c/4-1) of std_ulogic_vector(31 downto 0);
type boot_img_t is array (0 to BOOTROM_SIZE/4-1) of std_ulogic_vector(31 downto 0);
-- init function --
-- impure function: returns NOT the same result every time it is evaluated with the same arguments since the source file might have changed
@ -71,7 +75,7 @@ architecture neorv32_boot_rom_rtl of neorv32_boot_rom is
signal acc_en : std_ulogic;
signal rden : std_ulogic;
signal rdata : std_ulogic_vector(31 downto 0);
signal addr : std_ulogic_vector(index_size_f(boot_size_c/4)-1 downto 0);
signal addr : std_ulogic_vector(index_size_f(BOOTROM_SIZE/4)-1 downto 0);
-- bootloader image --
constant boot_img : boot_img_t := init_boot_rom(bootloader_init_image);
@ -80,8 +84,8 @@ begin
-- Access Control -------------------------------------------------------------------------
-- -------------------------------------------------------------------------------------------
acc_en <= '1' when (addr_i >= boot_base_c) and (addr_i < std_ulogic_vector(unsigned(boot_base_c) + boot_size_c)) else '0';
addr <= addr_i(index_size_f(boot_size_c/4)+1 downto 2); -- word aligned
acc_en <= '1' when (addr_i >= BOOTROM_BASE) and (addr_i < std_ulogic_vector(unsigned(BOOTROM_BASE) + BOOTROM_SIZE)) else '0';
addr <= addr_i(index_size_f(BOOTROM_SIZE/4)+1 downto 2); -- word aligned
-- Memory Access --------------------------------------------------------------------------