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| author | Clyne Sullivan <clyne@bitgloo.com> | 2024-10-06 11:30:25 -0400 |
|---|---|---|
| committer | Clyne Sullivan <clyne@bitgloo.com> | 2024-10-06 11:30:25 -0400 |
| commit | 294cf1320986f12efad7885836c31ef6a56f94dc (patch) | |
| tree | b1b46602d260e773ee987f1be048e76d423f6983 /src/timer.zig | |
| parent | 64df2e9f313ca8b22310f839ab50f7ec2628ec25 (diff) | |
systick driver
Diffstat (limited to 'src/timer.zig')
| -rw-r--r-- | src/timer.zig | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/src/timer.zig b/src/timer.zig new file mode 100644 index 0000000..21151c7 --- /dev/null +++ b/src/timer.zig @@ -0,0 +1,31 @@ +const interrupt = @import("interrupt.zig"); + +const sys_tick_type = packed struct { + enable: u1, + tickint: u1, + unused: u30, + + rvr: u32, + cvr: u32, + calib: u32, +}; + +var sys_tick: *volatile sys_tick_type = @ptrFromInt(0xE000E010); + +pub var ticks_raw: u32 = 0; + +pub fn initialize(freq: u32) void { + interrupt.register(.SysTick, tick); + sys_tick.rvr = 4000000 / 8 / freq; + sys_tick.tickint = 1; + sys_tick.enable = 1; +} + +fn tick() void { + ticks_raw += 1; +} + +pub fn ticks() u32 { + return @atomicLoad(u32, &ticks_raw, .acquire); +} + |