diff options
author | Christian Cunningham <cc@localhost> | 2021-12-03 09:55:06 -0700 |
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committer | Christian Cunningham <cc@localhost> | 2021-12-03 09:55:06 -0700 |
commit | c06fb44b7f63bbb94523f0f4d2908d34d22b94c2 (patch) | |
tree | 527c687aebaf9acb8be6e594d9ebb1dae4287d26 /src/drivers | |
parent | 72e74f2e3203dc9627f13e740e0d88091ff1d149 (diff) |
Started moving source files to subdirectories
Diffstat (limited to 'src/drivers')
-rw-r--r-- | src/drivers/uart.S | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/src/drivers/uart.S b/src/drivers/uart.S new file mode 100644 index 0000000..0864b7e --- /dev/null +++ b/src/drivers/uart.S @@ -0,0 +1,75 @@ +.section ".text" + +.globl uart_init +uart_init: + //*UART0_IMSC = 1 << 4; + // IGNORE OVERRUN + mov r2, #0x1038 + movt r2, #0x3F20 + mov r3, #0b10000 + str r3, [r2] + //*IRQ_ENABLE2 = 1 << 25; + mov r2, #0xB214 + movt r2, #0x3F00 + mov r3, #0 + movt r3, #0b1000000000 + str r3, [r2] + //*GPU_INTERRUPTS_ROUTING = 0x00; + // Route GPU interrupts to Core0 + mov r2, #0x000C + movt r2, #0x4000 + eor r3, r3 + str r3, [r2] + bx lr + +.globl uart_char +uart_char: + mov r2, #0x1000 + movt r2, #0x3f20 +uart_char.loop: + ldr r3, [r2, #24] + tst r3, #0b100000 + bne uart_char.loop + str r0, [r2] + bx lr + +.globl uart_string +uart_string: + push {r4, lr} + mov r4, r0 + ldrb r0, [r0] + cmp r0, #0 + popeq {r4, pc} +uart_string.loop: + bl uart_char + ldrb r0, [r4, #1]! + cmp r0, #0 + bne uart_string.loop + pop {r4, pc} + +.globl uart_hex +uart_hex: + push {r4, lr} + mov r2, #0x1000 + movt r2, #0x3f20 +uart_hex.loop: + ldr r3, [r2, #24] + tst r3, #0b100000 + bne uart_hex.loop + mov r3, #7 +uart_hex.hloop: + mov r1, r0 + asr r1, r3 + asr r1, r3 + asr r1, r3 + asr r1, r3 + and r1, #0xf + add r1, #0x30 + cmp r1, #0x3A + blt uart_hex.print + add r1, #7 +uart_hex.print: + str r1, [r2] + subs r3, #1 + bge uart_hex.hloop + pop {r4, pc} |