update linux-arm to use the asm intrin for freq

1 files changed, 29 insertions, 24 deletions

diff --git a/core/time/tsc_linux.odin b/core/time/tsc_linux.odin
index a83634414..92712f136 100644
--- a/core/time/tsc_linux.odin
+++ b/core/time/tsc_linux.odin
@@ -5,29 +5,34 @@ package time
 import linux "core:sys/linux"
 
 _get_tsc_frequency :: proc "contextless" () -> (u64, bool) {
-	// Get the file descriptor for the perf mapping
-	perf_attr := linux.Perf_Event_Attr{}
-	perf_attr.size = size_of(perf_attr)
-	perf_attr.type = .HARDWARE
-	perf_attr.config.hw = .INSTRUCTIONS
-	perf_attr.flags = {.Disabled, .Exclude_Kernel, .Exclude_HV}
-	fd, perf_errno := linux.perf_event_open(&perf_attr, linux.Pid(0), -1, linux.Fd(-1), {})
-	if perf_errno != nil {
-		return 0, false
+	if ODIN_ARCH == .arm64 {
+		freq = u64(intrinsics.arm64_read_cycle_counter_frequency())
+		return frequency, true
+	} else {
+		// Get the file descriptor for the perf mapping
+		perf_attr := linux.Perf_Event_Attr{}
+		perf_attr.size = size_of(perf_attr)
+		perf_attr.type = .HARDWARE
+		perf_attr.config.hw = .INSTRUCTIONS
+		perf_attr.flags = {.Disabled, .Exclude_Kernel, .Exclude_HV}
+		fd, perf_errno := linux.perf_event_open(&perf_attr, linux.Pid(0), -1, linux.Fd(-1), {})
+		if perf_errno != nil {
+			return 0, false
+		}
+		defer linux.close(fd)
+		// Map it into the memory
+		page_size : uint = 4096
+		addr, mmap_errno := linux.mmap(0, page_size, {.READ}, {.SHARED}, fd)
+		if mmap_errno != nil {
+			return 0, false
+		}
+		defer linux.munmap(addr, page_size)
+		// Get the frequency from the mapped page
+		event_page := cast(^linux.Perf_Event_Mmap_Page) addr
+		if .User_Time not_in event_page.cap.flags {
+			return 0, false
+		}
+		frequency := u64((u128(1_000_000_000) << u128(event_page.time_shift)) / u128(event_page.time_mult))
+		return frequency, true
 	}
-	defer linux.close(fd)
-	// Map it into the memory
-	page_size : uint = 4096
-	addr, mmap_errno := linux.mmap(0, page_size, {.READ}, {.SHARED}, fd)
-	if mmap_errno != nil {
-		return 0, false
-	}
-	defer linux.munmap(addr, page_size)
-	// Get the frequency from the mapped page
-	event_page := cast(^linux.Perf_Event_Mmap_Page) addr
-	if .User_Time not_in event_page.cap.flags {
-		return 0, false
-	}
-	frequency := u64((u128(1_000_000_000) << u128(event_page.time_shift)) / u128(event_page.time_mult))
-	return frequency, true
 }