diff options
| author | Jacques Comeaux <jacquesrcomeaux@protonmail.com> | 2024-05-20 23:19:14 -0500 |
|---|---|---|
| committer | Jacques Comeaux <jacquesrcomeaux@protonmail.com> | 2024-05-20 23:19:14 -0500 |
| commit | 7388c270069c2d1418539bca1d2789a6d468ecc2 (patch) | |
| tree | d3848031f6c2d4d45ec0a7c75b12a9f476680726 /setup/gpio.s | |
| parent | 7f47fc894d43739fb0107fd17e76f65ae2bf46bc (diff) | |
Make shared object for setup routines
Diffstat (limited to 'setup/gpio.s')
| -rw-r--r-- | setup/gpio.s | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/setup/gpio.s b/setup/gpio.s new file mode 100644 index 0000000..32e2c37 --- /dev/null +++ b/setup/gpio.s @@ -0,0 +1,23 @@ +.syntax unified +.cpu cortex-m0plus +.thumb + +.equ RESETS_BASE, 0x4000c000 +.equ RESET_OFST, 0x0 +.equ RESET_DONE_OFST, 0x8 + +.equ ATOMIC_CLEAR, 0x3000 + +.type setup_gpio, %function +.global setup_gpio + +setup_gpio: + ldr r1, =(RESETS_BASE + ATOMIC_CLEAR) + movs r0, 0b1 << 5 // IO_BANK0 + str r0, [r1, RESET_OFST] + ldr r1, =RESETS_BASE +1: + ldr r2, [r1, RESET_DONE_OFST] + tst r2, r0 + beq 1b + bx lr |