ke: add generic IPI mechanism

src/platform/pc/impl.zig

@@ -9,7 +9,7 @@ pub const smp = @import("smp.zig");
 
 const ki = r.ke.private;
 
-pub const name = "PC";
+pub const name: []const u8 = "PC";
 
 const com1 = 0x3F8;
 
@@ -113,10 +113,6 @@ pub fn arm_timer(deadline: r.Nanoseconds) void {
     apic.arm_timer(deadline);
 }
 
-pub fn send_resched_ipi(target_cpu: u32) void {
+pub fn send_ipi(target_cpu: u32) void {
     apic.send_ipi(smp.cpu_id_to_apic_id[target_cpu], 240, 0);
 }
-
-pub fn send_tlb_ipi(target_cpu: u32) void {
-    apic.send_ipi(smp.cpu_id_to_apic_id[target_cpu], 241, 0);
-}

src/platform/root.zig

@@ -3,6 +3,7 @@
 
 const config = @import("config");
 const r = @import("root");
+const rtl = @import("rtl");
 
 pub const impl = switch (config.arch) {
     .amd64 => @import("pc/impl.zig"),
@@ -11,6 +12,28 @@ pub const impl = switch (config.arch) {
 
 pub const acpi = @import("acpi/root.zig");
 
+const ImplSchema = struct {
+    pub const name: []const u8 = undefined;
+    pub fn early_init() void {}
+    pub fn late_init() void {}
+    pub fn debug_write(c: u8) void {
+        _ = c;
+    }
+    pub fn debug_read() u8 {
+        unreachable;
+    }
+    pub fn send_ipi(cpu: u32) void {
+        _ = cpu;
+    }
+    pub fn arm_timer(ns: r.Nanoseconds) void {
+        _ = ns;
+    }
+};
+
+comptime {
+    rtl.assert_interface(impl, ImplSchema);
+}
+
 /// Early platform-specific initialization, called before anything else.
 pub inline fn early_init() void {
     return impl.early_init();
@@ -37,5 +60,10 @@ pub inline fn arm_timer(ns: r.Nanoseconds) void {
     return impl.arm_timer(ns);
 }
 
+/// Send an inter-processor interrupt (IPI) to a target CPU.
+pub inline fn send_ipi(cpu: u32) void {
+    return impl.send_ipi(cpu);
+}
+
 /// Pretty name for the platform.
 pub const name = impl.name;