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amd64/tsc: reformat

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Loïc Grégoire
2026-08-19 18:04:30 -04:00
parent ee0c6aad67
commit 322714d508
1 changed files with 18 additions and 5 deletions
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src/platform/pc/tsc.zig
+18 -5
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@@ -18,7 +18,10 @@ pub var tsc_timer: ke.TimeCounter = .{
pub fn init() linksection(r.init) void {
if (!amd64.cpu_features.invariant_tsc) {
log.info("invariant TSC not supported (get a new PC), using fallback", .{});
log.info(
"invariant TSC not supported (get a new PC), using fallback",
.{},
);
if (ke.time.best()) |best| {
log.info("using {s} as timecounter source", .{best.name});
}
@@ -28,9 +31,14 @@ pub fn init() linksection(r.init) void {
// Try using cpuid leaf 0x15 to get the TSC frequency.
const cpuid_state = amd64.cpuid(0x15, 0);
if (cpuid_state.ebx != 0 and cpuid_state.ecx != 0 and cpuid_state.eax != 0) {
if (cpuid_state.ebx != 0 and cpuid_state.ecx != 0 and
cpuid_state.eax != 0)
{
const tsc_freq = (cpuid_state.ebx / cpuid_state.eax) * cpuid_state.ecx;
log.info("TSC frequency determined via CPUID: {} Hz", .{tsc_freq});
log.info(
"TSC frequency determined via CPUID: {} Hz",
.{tsc_freq},
);
tsc_timer.frequency = tsc_freq;
ke.time.register_source(&tsc_timer);
@@ -56,7 +64,8 @@ pub fn init() linksection(r.init) void {
const runs = 5;
const calib_time = 10 * std.time.ns_per_ms;
// Sleep for 10ms `runs` times and measure the TSC frequency, then average the middle values to get a stable estimate.
// Sleep for 10ms `runs` times and measure the TSC frequency,
// then average the middle values to get a stable estimate.
var freqs: [runs]u64 = undefined;
for (0..runs) |i| {
@@ -75,7 +84,11 @@ pub fn init() linksection(r.init) void {
ke.time.register_source(&tsc_timer);
log.info("frequency calibrated using {s}: {}.{} MHz", .{ best.name, tsc_timer.frequency / 1_000_000, (tsc_timer.frequency % 1_000_000) / 1000 });
log.info("frequency calibrated using {s}: {}.{} MHz", .{
best.name,
tsc_timer.frequency / 1_000_000,
(tsc_timer.frequency % 1_000_000) / 1000,
});
}
fn read_tsc() u64 {