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			505 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			VHDL
		
	
			
		
		
	
	
			505 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			VHDL
		
	
| library ieee;
 | |
| use ieee.std_logic_1164.all;
 | |
| use ieee.numeric_std.all;
 | |
| 
 | |
| library work;
 | |
| use work.wishbone_types.all;
 | |
| 
 | |
| entity toplevel is
 | |
|     generic (
 | |
|         MEMORY_SIZE        : integer  := 16384;
 | |
|         RAM_INIT_FILE      : string   := "firmware.hex";
 | |
|         RESET_LOW          : boolean  := true;
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|         CLK_INPUT          : positive := 100000000;
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|         CLK_FREQUENCY      : positive := 100000000;
 | |
|         HAS_FPU            : boolean  := true;
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|         HAS_BTC            : boolean  := false;
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|         USE_LITEDRAM       : boolean  := true;
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|         NO_BRAM            : boolean  := true;
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|         SCLK_STARTUPE2     : boolean := false;
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|         SPI_FLASH_OFFSET   : integer := 4194304;
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|         SPI_FLASH_DEF_CKDV : natural := 1;
 | |
|         SPI_FLASH_DEF_QUAD : boolean := true;
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|         LOG_LENGTH         : natural := 0;
 | |
|         UART_IS_16550      : boolean  := true;
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|         HAS_UART1          : boolean  := false;
 | |
|         USE_LITESDCARD     : boolean := true;
 | |
|         ICACHE_NUM_LINES   : natural := 64;
 | |
|         NGPIO              : natural := 0
 | |
|         );
 | |
|     port(
 | |
|         ext_clk   : in  std_ulogic;
 | |
|         ext_rst_n : in  std_ulogic;
 | |
| 
 | |
|         -- UART0 signals:
 | |
|         pin_gpio_0 : out std_ulogic;
 | |
|         pin_gpio_1 : in  std_ulogic;
 | |
| 
 | |
|         -- LEDs
 | |
|         led0_b  : out std_ulogic;
 | |
|         led0_g  : out std_ulogic;
 | |
|         led0_r  : out std_ulogic;
 | |
| 
 | |
|         -- SPI
 | |
|         spi_flash_cs_n   : out std_ulogic;
 | |
|         spi_flash_mosi   : inout std_ulogic;
 | |
|         spi_flash_miso   : inout std_ulogic;
 | |
|         spi_flash_wp_n   : inout std_ulogic;
 | |
|         spi_flash_hold_n : inout std_ulogic;
 | |
| 
 | |
|         -- SD card wires
 | |
|         sdcard_data   : inout std_ulogic_vector(3 downto 0);
 | |
|         sdcard_cmd    : inout std_ulogic;
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|         sdcard_clk    : out   std_ulogic;
 | |
|         sdcard_cd     : in    std_ulogic;
 | |
| 
 | |
|         -- DRAM wires
 | |
|         ddram_a       : out std_ulogic_vector(13 downto 0);
 | |
|         ddram_ba      : out std_ulogic_vector(2 downto 0);
 | |
|         ddram_ras_n   : out std_ulogic;
 | |
|         ddram_cas_n   : out std_ulogic;
 | |
|         ddram_we_n    : out std_ulogic;
 | |
|         ddram_cs_n    : out std_ulogic;
 | |
|         ddram_dm      : out std_ulogic_vector(1 downto 0);
 | |
|         ddram_dq      : inout std_ulogic_vector(15 downto 0);
 | |
|         ddram_dqs_p   : inout std_ulogic_vector(1 downto 0);
 | |
|         ddram_clk_p   : out std_ulogic_vector(0 downto 0);
 | |
|         -- only the positive differential pin is instantiated
 | |
|         --ddram_dqs_n   : inout std_ulogic_vector(1 downto 0);
 | |
|         --ddram_clk_n   : out std_ulogic_vector(0 downto 0);
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|         ddram_cke     : out std_ulogic;
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|         ddram_odt     : out std_ulogic;
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|         ddram_reset_n : out std_ulogic;
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| 
 | |
|         ddram_gnd      : out std_ulogic_vector(1 downto 0);
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|         ddram_vccio    : out std_ulogic_vector(5 downto 0)
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|         );
 | |
| end entity toplevel;
 | |
| 
 | |
| architecture behaviour of toplevel is
 | |
| 
 | |
|     -- Reset signals:
 | |
|     signal soc_rst : std_ulogic;
 | |
|     signal pll_rst : std_ulogic;
 | |
| 
 | |
|     -- Internal clock signals:
 | |
|     signal system_clk        : std_ulogic;
 | |
|     signal system_clk_locked : std_ulogic;
 | |
| 
 | |
|     -- External IOs from the SoC
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|     signal wb_ext_io_in        : wb_io_master_out;
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|     signal wb_ext_io_out       : wb_io_slave_out;
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|     signal wb_ext_is_dram_csr  : std_ulogic;
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|     signal wb_ext_is_dram_init : std_ulogic;
 | |
|     signal wb_ext_is_sdcard    : std_ulogic;
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| 
 | |
|     -- DRAM main data wishbone connection
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|     signal wb_dram_in          : wishbone_master_out;
 | |
|     signal wb_dram_out         : wishbone_slave_out;
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| 
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|     -- DRAM control wishbone connection
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|     signal wb_dram_ctrl_out    : wb_io_slave_out := wb_io_slave_out_init;
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| 
 | |
|     -- LiteSDCard connection
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|     signal ext_irq_sdcard      : std_ulogic := '0';
 | |
|     signal wb_sdcard_out       : wb_io_slave_out := wb_io_slave_out_init;
 | |
|     signal wb_sddma_out        : wb_io_master_out := wb_io_master_out_init;
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|     signal wb_sddma_in         : wb_io_slave_out;
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|     signal wb_sddma_nr         : wb_io_master_out;
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|     signal wb_sddma_ir         : wb_io_slave_out;
 | |
|     -- for conversion from non-pipelined wishbone to pipelined
 | |
|     signal wb_sddma_stb_sent   : std_ulogic;
 | |
| 
 | |
|     -- Status LED
 | |
|     signal led0_b_pwm : std_ulogic;
 | |
|     signal led0_r_pwm : std_ulogic;
 | |
|     signal led0_g_pwm : std_ulogic;
 | |
| 
 | |
|     -- Dumb PWM for the LEDs, those RGB LEDs are too bright otherwise
 | |
|     signal pwm_counter  : std_ulogic_vector(8 downto 0);
 | |
| 
 | |
|     -- SPI flash
 | |
|     signal spi_sck     : std_ulogic;
 | |
|     signal spi_cs_n    : std_ulogic;
 | |
|     signal spi_sdat_o  : std_ulogic_vector(3 downto 0);
 | |
|     signal spi_sdat_oe : std_ulogic_vector(3 downto 0);
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|     signal spi_sdat_i  : std_ulogic_vector(3 downto 0);
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| 
 | |
|     -- GPIO
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|     signal gpio_in     : std_ulogic_vector(NGPIO - 1 downto 0);
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|     signal gpio_out    : std_ulogic_vector(NGPIO - 1 downto 0);
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|     signal gpio_dir    : std_ulogic_vector(NGPIO - 1 downto 0);
 | |
| 
 | |
|     -- Fixup various memory sizes based on generics
 | |
|     function get_bram_size return natural is
 | |
|     begin
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|         if USE_LITEDRAM and NO_BRAM then
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|             return 0;
 | |
|         else
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|             return MEMORY_SIZE;
 | |
|         end if;
 | |
|     end function;
 | |
| 
 | |
|     function get_payload_size return natural is
 | |
|     begin
 | |
|         if USE_LITEDRAM and NO_BRAM then
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|             return MEMORY_SIZE;
 | |
|         else
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|             return 0;
 | |
|         end if;
 | |
|     end function;
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| 
 | |
|     constant BRAM_SIZE    : natural := get_bram_size;
 | |
|     constant PAYLOAD_SIZE : natural := get_payload_size;
 | |
| 
 | |
|     COMPONENT USRMCLK
 | |
|         PORT(
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|             USRMCLKI : IN STD_ULOGIC;
 | |
|             USRMCLKTS : IN STD_ULOGIC
 | |
|         );
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|     END COMPONENT;
 | |
|     attribute syn_noprune: boolean ;
 | |
|     attribute syn_noprune of USRMCLK: component is true;
 | |
| 
 | |
| begin
 | |
| 
 | |
|     -- Main SoC
 | |
|     soc0: entity work.soc
 | |
|         generic map(
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|             MEMORY_SIZE        => BRAM_SIZE,
 | |
|             RAM_INIT_FILE      => RAM_INIT_FILE,
 | |
|             SIM                => false,
 | |
|             CLK_FREQ           => CLK_FREQUENCY,
 | |
|             HAS_FPU            => HAS_FPU,
 | |
|             HAS_BTC            => HAS_BTC,
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|             HAS_DRAM           => USE_LITEDRAM,
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|             DRAM_SIZE          => 256 * 1024 * 1024,
 | |
|             DRAM_INIT_SIZE     => PAYLOAD_SIZE,
 | |
|             HAS_SPI_FLASH      => true,
 | |
|             SPI_FLASH_DLINES   => 4,
 | |
|             SPI_FLASH_OFFSET   => SPI_FLASH_OFFSET,
 | |
|             SPI_FLASH_DEF_CKDV => SPI_FLASH_DEF_CKDV,
 | |
|             SPI_FLASH_DEF_QUAD => SPI_FLASH_DEF_QUAD,
 | |
|             LOG_LENGTH         => LOG_LENGTH,
 | |
|             UART0_IS_16550     => UART_IS_16550,
 | |
|             HAS_UART1          => HAS_UART1,
 | |
|             HAS_SD_CARD        => USE_LITESDCARD,
 | |
|             ICACHE_NUM_LINES   => ICACHE_NUM_LINES,
 | |
|             NGPIO              => NGPIO
 | |
|             )
 | |
|         port map (
 | |
|             -- System signals
 | |
|             system_clk        => system_clk,
 | |
|             rst               => soc_rst,
 | |
| 
 | |
|             -- UART signals
 | |
|             uart0_txd         => pin_gpio_0,
 | |
|             uart0_rxd         => pin_gpio_1,
 | |
| 
 | |
| 	    -- UART1 signals
 | |
| 	    --uart1_txd         => uart_pmod_tx,
 | |
| 	    --uart1_rxd         => uart_pmod_rx,
 | |
| 
 | |
|             -- SPI signals
 | |
|             spi_flash_sck     => spi_sck,
 | |
|             spi_flash_cs_n    => spi_cs_n,
 | |
|             spi_flash_sdat_o  => spi_sdat_o,
 | |
|             spi_flash_sdat_oe => spi_sdat_oe,
 | |
|             spi_flash_sdat_i  => spi_sdat_i,
 | |
| 
 | |
|             -- GPIO signals
 | |
|             gpio_in           => gpio_in,
 | |
|             gpio_out          => gpio_out,
 | |
|             gpio_dir          => gpio_dir,
 | |
| 
 | |
|             -- External interrupts
 | |
|             ext_irq_sdcard    => ext_irq_sdcard,
 | |
| 
 | |
|             -- DRAM wishbone
 | |
|             wb_dram_in           => wb_dram_in,
 | |
|             wb_dram_out          => wb_dram_out,
 | |
| 
 | |
|             -- IO wishbone
 | |
|             wb_ext_io_in         => wb_ext_io_in,
 | |
|             wb_ext_io_out        => wb_ext_io_out,
 | |
|             wb_ext_is_dram_csr   => wb_ext_is_dram_csr,
 | |
|             wb_ext_is_dram_init  => wb_ext_is_dram_init,
 | |
|             wb_ext_is_sdcard     => wb_ext_is_sdcard,
 | |
| 
 | |
|             -- DMA wishbone
 | |
|             wishbone_dma_in      => wb_sddma_in,
 | |
|             wishbone_dma_out     => wb_sddma_out
 | |
|             );
 | |
| 
 | |
|     -- SPI Flash
 | |
|     --
 | |
|     spi_flash_cs_n   <= spi_cs_n;
 | |
|     spi_flash_mosi   <= spi_sdat_o(0) when spi_sdat_oe(0) = '1' else 'Z';
 | |
|     spi_flash_miso   <= spi_sdat_o(1) when spi_sdat_oe(1) = '1' else 'Z';
 | |
|     spi_flash_wp_n   <= spi_sdat_o(2) when spi_sdat_oe(2) = '1' else 'Z';
 | |
|     spi_flash_hold_n <= spi_sdat_o(3) when spi_sdat_oe(3) = '1' else 'Z';
 | |
|     spi_sdat_i(0)    <= spi_flash_mosi;
 | |
|     spi_sdat_i(1)    <= spi_flash_miso;
 | |
|     spi_sdat_i(2)    <= spi_flash_wp_n;
 | |
|     spi_sdat_i(3)    <= spi_flash_hold_n;
 | |
| 
 | |
|     uclk: USRMCLK port map (
 | |
|         USRMCLKI => spi_sck,
 | |
|         USRMCLKTS => '0'
 | |
|         );
 | |
| 
 | |
|     nodram: if not USE_LITEDRAM generate
 | |
|         signal ddram_clk_dummy : std_ulogic;
 | |
|     begin
 | |
|         reset_controller: entity work.soc_reset
 | |
|             generic map(
 | |
|                 RESET_LOW => RESET_LOW
 | |
|                 )
 | |
|             port map(
 | |
|                 ext_clk => ext_clk,
 | |
|                 pll_clk => system_clk,
 | |
|                 pll_locked_in => system_clk_locked,
 | |
|                 ext_rst_in => ext_rst_n,
 | |
|                 pll_rst_out => pll_rst,
 | |
|                 rst_out => soc_rst
 | |
|                 );
 | |
| 
 | |
|         clkgen: entity work.clock_generator
 | |
|             generic map(
 | |
|                 CLK_INPUT_HZ => CLK_INPUT,
 | |
|                 CLK_OUTPUT_HZ => CLK_FREQUENCY
 | |
|                 )
 | |
|             port map(
 | |
|                 ext_clk => ext_clk,
 | |
|                 pll_rst_in => pll_rst,
 | |
|                 pll_clk_out => system_clk,
 | |
|                 pll_locked_out => system_clk_locked
 | |
|                 );
 | |
| 
 | |
|         led0_b_pwm <= '1';
 | |
|         led0_r_pwm <= '1';
 | |
|         led0_g_pwm <= '0';
 | |
| 
 | |
|     end generate;
 | |
| 
 | |
|     has_dram: if USE_LITEDRAM generate
 | |
|         signal dram_init_done  : std_ulogic;
 | |
|         signal dram_init_error : std_ulogic;
 | |
|         signal dram_sys_rst    : std_ulogic;
 | |
|         signal rst_gen_rst     : std_ulogic;
 | |
|     begin
 | |
| 
 | |
|         -- Eventually dig out the frequency from
 | |
|         -- litesdram generate.py sys_clk_freq
 | |
|         -- but for now, assert it's 48Mhz for orangecrab
 | |
|         assert CLK_FREQUENCY = 48000000;
 | |
| 
 | |
|         reset_controller: entity work.soc_reset
 | |
|             generic map(
 | |
|                 RESET_LOW => RESET_LOW,
 | |
|                 PLL_RESET_BITS => 18,
 | |
|                 SOC_RESET_BITS => 1
 | |
|                 )
 | |
|             port map(
 | |
|                 ext_clk => ext_clk,
 | |
|                 pll_clk => system_clk,
 | |
|                 pll_locked_in => system_clk_locked,
 | |
|                 ext_rst_in => ext_rst_n,
 | |
|                 pll_rst_out => pll_rst,
 | |
|                 rst_out => rst_gen_rst
 | |
|                 );
 | |
| 
 | |
|         -- Generate SoC reset
 | |
|         soc_rst_gen: process(system_clk)
 | |
|         begin
 | |
|             if ext_rst_n = '0' then
 | |
|                 soc_rst <= '1';
 | |
|             elsif rising_edge(system_clk) then
 | |
|                 soc_rst <= dram_sys_rst or not system_clk_locked;
 | |
|             end if;
 | |
|         end process;
 | |
| 
 | |
|         dram: entity work.litedram_wrapper
 | |
|             generic map(
 | |
|                 DRAM_ABITS => 24,
 | |
|                 DRAM_ALINES => 14,
 | |
|                 DRAM_DLINES => 16,
 | |
|                 DRAM_CKLINES => 1,
 | |
|                 DRAM_PORT_WIDTH => 128,
 | |
|                 NUM_LINES => 8, -- reduce from default of 64 to make smaller/timing
 | |
|                 PAYLOAD_FILE => RAM_INIT_FILE,
 | |
|                 PAYLOAD_SIZE => PAYLOAD_SIZE
 | |
|                 )
 | |
|             port map(
 | |
|                 clk_in          => ext_clk,
 | |
|                 rst             => pll_rst,
 | |
|                 system_clk      => system_clk,
 | |
|                 system_reset    => dram_sys_rst,
 | |
|                 pll_locked      => system_clk_locked,
 | |
| 
 | |
|                 wb_in           => wb_dram_in,
 | |
|                 wb_out          => wb_dram_out,
 | |
|                 wb_ctrl_in      => wb_ext_io_in,
 | |
|                 wb_ctrl_out     => wb_dram_ctrl_out,
 | |
|                 wb_ctrl_is_csr  => wb_ext_is_dram_csr,
 | |
|                 wb_ctrl_is_init => wb_ext_is_dram_init,
 | |
| 
 | |
|                 init_done       => dram_init_done,
 | |
|                 init_error      => dram_init_error,
 | |
| 
 | |
|                 ddram_a         => ddram_a,
 | |
|                 ddram_ba        => ddram_ba,
 | |
|                 ddram_ras_n     => ddram_ras_n,
 | |
|                 ddram_cas_n     => ddram_cas_n,
 | |
|                 ddram_we_n      => ddram_we_n,
 | |
|                 ddram_cs_n      => ddram_cs_n,
 | |
|                 ddram_dm        => ddram_dm,
 | |
|                 ddram_dq        => ddram_dq,
 | |
|                 ddram_dqs_p     => ddram_dqs_p,
 | |
|                 ddram_clk_p     => ddram_clk_p,
 | |
|                 -- only the positive differential pin is instantiated
 | |
|                 --ddram_dqs_n     => ddram_dqs_n,
 | |
|                 --ddram_clk_n     => ddram_clk_n,
 | |
|                 ddram_cke       => ddram_cke,
 | |
|                 ddram_odt       => ddram_odt,
 | |
| 
 | |
|                 ddram_reset_n   => ddram_reset_n
 | |
|                 );
 | |
| 
 | |
|         ddram_gnd <= "00";
 | |
|         -- for power consumption.
 | |
|         -- https://github.com/orangecrab-fpga/orangecrab-hardware/issues/19#issuecomment-683479378
 | |
|         ddram_vccio <= "111111";
 | |
| 
 | |
|         led0_b_pwm <= not dram_init_done;
 | |
|         led0_r_pwm <= dram_init_error;
 | |
|         led0_g_pwm <= dram_init_done and not dram_init_error;
 | |
| 
 | |
|     end generate;
 | |
| 
 | |
| 
 | |
|     -- SD card pmod
 | |
|     has_sdcard : if USE_LITESDCARD generate
 | |
|         component litesdcard_core port (
 | |
|             clk           : in    std_ulogic;
 | |
|             rst           : in    std_ulogic;
 | |
|             -- wishbone for accessing control registers
 | |
|             wb_ctrl_adr   : in    std_ulogic_vector(29 downto 0);
 | |
|             wb_ctrl_dat_w : in    std_ulogic_vector(31 downto 0);
 | |
|             wb_ctrl_dat_r : out   std_ulogic_vector(31 downto 0);
 | |
|             wb_ctrl_sel   : in    std_ulogic_vector(3 downto 0);
 | |
|             wb_ctrl_cyc   : in    std_ulogic;
 | |
|             wb_ctrl_stb   : in    std_ulogic;
 | |
|             wb_ctrl_ack   : out   std_ulogic;
 | |
|             wb_ctrl_we    : in    std_ulogic;
 | |
|             wb_ctrl_cti   : in    std_ulogic_vector(2 downto 0);
 | |
|             wb_ctrl_bte   : in    std_ulogic_vector(1 downto 0);
 | |
|             wb_ctrl_err   : out   std_ulogic;
 | |
|             -- wishbone for SD card core to use for DMA
 | |
|             wb_dma_adr    : out   std_ulogic_vector(29 downto 0);
 | |
|             wb_dma_dat_w  : out   std_ulogic_vector(31 downto 0);
 | |
|             wb_dma_dat_r  : in    std_ulogic_vector(31 downto 0);
 | |
|             wb_dma_sel    : out   std_ulogic_vector(3 downto 0);
 | |
|             wb_dma_cyc    : out   std_ulogic;
 | |
|             wb_dma_stb    : out   std_ulogic;
 | |
|             wb_dma_ack    : in    std_ulogic;
 | |
|             wb_dma_we     : out   std_ulogic;
 | |
|             wb_dma_cti    : out   std_ulogic_vector(2 downto 0);
 | |
|             wb_dma_bte    : out   std_ulogic_vector(1 downto 0);
 | |
|             wb_dma_err    : in    std_ulogic;
 | |
|             -- connections to SD card
 | |
|             sdcard_data   : inout std_ulogic_vector(3 downto 0);
 | |
|             sdcard_cmd    : inout std_ulogic;
 | |
|             sdcard_clk    : out   std_ulogic;
 | |
|             sdcard_cd     : in    std_ulogic;
 | |
|             irq           : out   std_ulogic
 | |
|             );
 | |
|         end component;
 | |
| 
 | |
|         signal wb_sdcard_cyc : std_ulogic;
 | |
|         signal wb_sdcard_adr : std_ulogic_vector(29 downto 0);
 | |
| 
 | |
|     begin
 | |
|         litesdcard : litesdcard_core
 | |
|             port map (
 | |
|                 clk           => system_clk,
 | |
|                 rst           => soc_rst,
 | |
|                 wb_ctrl_adr   => wb_sdcard_adr,
 | |
|                 wb_ctrl_dat_w => wb_ext_io_in.dat,
 | |
|                 wb_ctrl_dat_r => wb_sdcard_out.dat,
 | |
|                 wb_ctrl_sel   => wb_ext_io_in.sel,
 | |
|                 wb_ctrl_cyc   => wb_sdcard_cyc,
 | |
|                 wb_ctrl_stb   => wb_ext_io_in.stb,
 | |
|                 wb_ctrl_ack   => wb_sdcard_out.ack,
 | |
|                 wb_ctrl_we    => wb_ext_io_in.we,
 | |
|                 wb_ctrl_cti   => "000",
 | |
|                 wb_ctrl_bte   => "00",
 | |
|                 wb_ctrl_err   => open,
 | |
|                 wb_dma_adr    => wb_sddma_nr.adr,
 | |
|                 wb_dma_dat_w  => wb_sddma_nr.dat,
 | |
|                 wb_dma_dat_r  => wb_sddma_ir.dat,
 | |
|                 wb_dma_sel    => wb_sddma_nr.sel,
 | |
|                 wb_dma_cyc    => wb_sddma_nr.cyc,
 | |
|                 wb_dma_stb    => wb_sddma_nr.stb,
 | |
|                 wb_dma_ack    => wb_sddma_ir.ack,
 | |
|                 wb_dma_we     => wb_sddma_nr.we,
 | |
|                 wb_dma_cti    => open,
 | |
|                 wb_dma_bte    => open,
 | |
|                 wb_dma_err    => '0',
 | |
|                 sdcard_data   => sdcard_data,
 | |
|                 sdcard_cmd    => sdcard_cmd,
 | |
|                 sdcard_clk    => sdcard_clk,
 | |
|                 sdcard_cd     => sdcard_cd,
 | |
|                 irq           => ext_irq_sdcard
 | |
|                 );
 | |
| 
 | |
|         -- Gate cyc with chip select from SoC
 | |
|         wb_sdcard_cyc <= wb_ext_io_in.cyc and wb_ext_is_sdcard;
 | |
| 
 | |
|         wb_sdcard_adr <= x"0000" & wb_ext_io_in.adr(13 downto 0);
 | |
| 
 | |
|         wb_sdcard_out.stall <= not wb_sdcard_out.ack;
 | |
| 
 | |
|         -- Convert non-pipelined DMA wishbone to pipelined by suppressing
 | |
|         -- non-acknowledged strobes
 | |
|         process(system_clk)
 | |
|         begin
 | |
|             if rising_edge(system_clk) then
 | |
|                 wb_sddma_out <= wb_sddma_nr;
 | |
|                 if wb_sddma_stb_sent = '1' or
 | |
|                     (wb_sddma_out.stb = '1' and wb_sddma_in.stall = '0') then
 | |
|                     wb_sddma_out.stb <= '0';
 | |
|                 end if;
 | |
|                 if wb_sddma_nr.cyc = '0' or wb_sddma_ir.ack = '1' then
 | |
|                     wb_sddma_stb_sent <= '0';
 | |
|                 elsif wb_sddma_in.stall = '0' then
 | |
|                     wb_sddma_stb_sent <= wb_sddma_nr.stb;
 | |
|                 end if;
 | |
|                 wb_sddma_ir <= wb_sddma_in;
 | |
|             end if;
 | |
|         end process;
 | |
| 
 | |
|     end generate;
 | |
| 
 | |
|     -- Mux WB response on the IO bus
 | |
|     wb_ext_io_out <= wb_sdcard_out when wb_ext_is_sdcard = '1' else
 | |
|                      wb_dram_ctrl_out;
 | |
| 
 | |
|     leds_pwm : process(system_clk)
 | |
|     begin
 | |
|         if rising_edge(system_clk) then
 | |
|             pwm_counter <= std_ulogic_vector(signed(pwm_counter) + 1);
 | |
|             if pwm_counter(8 downto 4) = "00000" then
 | |
|                 led0_b <= led0_b_pwm;
 | |
|                 led0_r <= led0_r_pwm;
 | |
|                 led0_g <= led0_g_pwm;
 | |
|             else
 | |
|                 led0_b <= '0';
 | |
|                 led0_r <= '0';
 | |
|                 led0_g <= '0';
 | |
|             end if;
 | |
|         end if;
 | |
|     end process;
 | |
| 
 | |
| end architecture behaviour;
 |