diff options
| author | Megan Wachs <megan@sifive.com> | 2016-07-20 23:59:02 +0000 |
|---|---|---|
| committer | Megan Wachs <megan@sifive.com> | 2016-07-26 08:40:12 -0700 |
| commit | 2887165ae2990e7f93038f3220ed74ee429b5244 (patch) | |
| tree | 13c4cb83e47d6ab390e0465e883acf0973611e8e /bootrom/demo | |
| parent | a2d28c8318ab3ed40b3674aeee8b9487a3129f15 (diff) | |
Initial Checkin
Diffstat (limited to 'bootrom/demo')
| -rw-r--r-- | bootrom/demo/Makefile | 5 | ||||
| -rw-r--r-- | bootrom/demo/demo.S | 71 | ||||
| -rw-r--r-- | bootrom/demo/hello_msg.txt | 37 |
3 files changed, 113 insertions, 0 deletions
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.
+
+
+
+
+
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