From 2887165ae2990e7f93038f3220ed74ee429b5244 Mon Sep 17 00:00:00 2001 From: Megan Wachs Date: Wed, 20 Jul 2016 23:59:02 +0000 Subject: Initial Checkin --- bootrom/demo/Makefile | 5 ++++ bootrom/demo/demo.S | 71 ++++++++++++++++++++++++++++++++++++++++++++++ bootrom/demo/hello_msg.txt | 37 ++++++++++++++++++++++++ 3 files changed, 113 insertions(+) create mode 100644 bootrom/demo/Makefile create mode 100644 bootrom/demo/demo.S create mode 100644 bootrom/demo/hello_msg.txt (limited to 'bootrom/demo') diff --git a/bootrom/demo/Makefile b/bootrom/demo/Makefile new file mode 100644 index 0000000..dfe3663 --- /dev/null +++ b/bootrom/demo/Makefile @@ -0,0 +1,5 @@ +PROG := demo +SRCS := demo.S +EXTRAS := hello_msg.txt + +include ../bram.mk diff --git a/bootrom/demo/demo.S b/bootrom/demo/demo.S new file mode 100644 index 0000000..c6f2618 --- /dev/null +++ b/bootrom/demo/demo.S @@ -0,0 +1,71 @@ +#define UART_BASE 0x48000000 +#define SPI_BASE 0x48001000 +#define GPIO_BASE 0x48002000 + +#ifndef CFG_STRING +#error Must define CFG_STRING +#endif + + .globl _start +_start: + j uart_init + nop + nop + .word cfgstr + +uart_init: + // a1 = UART_TX + // a2 = hello_msg_end + // for (a0 = hello_msg_start; a0 != a2; ++ a0){ + // while (a3 = TX_READY == 0); + // a3 = *a0 + // *a1 = a3 + // } + + la a0, hello_msg_start + la a2, hello_msg_end + li a1, UART_BASE + +uart_loop: + lw a3, 4(a1) // Wait until non-zero (uart can send data). + beqz a3, uart_loop + + lb a3, 0(a0) // read the next character in hello_msg + sw a3, 0(a1) // Write the current character. + addi a0, a0, 1 // increment the pointer. + bne a0, a2, uart_loop + +gpio_init: + li a0, GPIO_BASE + li t0, 0xFFFF0000 + sw t0, 4(a0) + +gpio_loop: + // For Red LEDs, increment manually. + li t0, 0x1 + sw t0, (a0) + li t0, 0x2 + sw t0, (a0) + li t0, 0x4 + sw t0, (a0) + li t0, 0x8 + sw t0, (a0) + + // For Blue and Green LEDs, sample the switches & buttons + + lw t0, (a0) + srli t0, t0, 16 + andi t0, t0, 0xFF + slli t0, t0, 4 + sw t0, (a0) + + j gpio_loop + + .section .rodata + +hello_msg_start: + .incbin "hello_msg.txt" +hello_msg_end: + +cfgstr: + .incbin CFG_STRING diff --git a/bootrom/demo/hello_msg.txt b/bootrom/demo/hello_msg.txt new file mode 100644 index 0000000..c3cb3f2 --- /dev/null +++ b/bootrom/demo/hello_msg.txt @@ -0,0 +1,37 @@ + + SIFIVE, INC. + + 5555555555555555555555555 + 5555 5555 + 5555 5555 + 5555 5555 + 5555 5555555555555555555555 + 5555 555555555555555555555555 + 5555 5555 + 5555 5555 + 5555 5555 +5555555555555555555555555555 55555 + 55555 555555555 55555 + 55555 55555 55555 + 55555 5 55555 + 55555 55555 + 55555 55555 + 55555 55555 + 55555 55555 + 55555 55555 + 555555555 + 55555 + 5 + + SiFive RISC-V Coreplex + +Welcome to the Arty FPGA Freedom E Dev Kit. +The red LEDs are blinking very fast and appear +dim. Try pressing the buttons and switches to control +the blue and green LEDs. You can try using the +debugger to step through the boot code. + + + + + -- cgit v1.2.3