From 627150b17061fb503b543812958cde27dd189a35 Mon Sep 17 00:00:00 2001
From: Quinten Kock <quintenkock@gmail.com>
Date: Sat, 30 Jan 2021 22:10:11 +0100
Subject: [PATCH] implement CPUID

---
 kernel/src/arch/i386/i386.zig     |  1 +
 kernel/src/arch/x86/cpuid.zig     | 54 +++++++++++++++++++++++++++++++
 kernel/src/arch/x86/x86.zig       |  1 +
 kernel/src/arch/x86_64/x86_64.zig |  2 +-
 4 files changed, 57 insertions(+), 1 deletion(-)
 create mode 100644 kernel/src/arch/x86/cpuid.zig

diff --git a/kernel/src/arch/i386/i386.zig b/kernel/src/arch/i386/i386.zig
index e69de29..d0435af 100644
--- a/kernel/src/arch/i386/i386.zig
+++ b/kernel/src/arch/i386/i386.zig
@@ -0,0 +1 @@
+usingnamespace @import("../x86/x86.zig");
\ No newline at end of file
diff --git a/kernel/src/arch/x86/cpuid.zig b/kernel/src/arch/x86/cpuid.zig
new file mode 100644
index 0000000..b259236
--- /dev/null
+++ b/kernel/src/arch/x86/cpuid.zig
@@ -0,0 +1,54 @@
+const std = @import("std");
+const cpuid_c = @cImport(@cInclude("cpuid.h"));
+
+const cpuid_ret = struct {
+    eax: u32,
+    ebx: u32,
+    ecx: u32,
+    edx: u32,
+};
+
+// static inline int cpuid_string(int code, uint32_t where[4]) {
+//   asm volatile("cpuid":"=a"(*where),"=b"(*(where+1)),
+//                "=c"(*(where+2)),"=d"(*(where+3)):"a"(code));
+//   return (int)where[0];
+// }
+
+fn getcpuid(leaf: u32) [4]u32 {
+    // cpuid_c.__cpuid(leaf, &ret.eax, &ret.ebx, &ret.ecx, &ret.edx);
+    var eax: u32 = undefined;
+    var ebx: u32 = undefined;
+    var ecx: u32 = undefined;
+    var edx: u32 = undefined;
+    asm volatile("cpuid"
+        : [eax] "={eax}" (eax),
+          [ebx] "={ebx}" (ebx),
+          [ecx] "={ecx}" (ecx),
+          [edx] "={edx}" (edx),
+        : [leaf] "{eax}" (leaf)
+        :
+    );
+    std.log.info("cpuid {x}: {x} {x} {x} {x}", .{leaf, eax, ebx, ecx, edx});
+    return .{eax, ebx, ecx, edx};
+}
+
+var vendor: [12]u8 = undefined;
+pub fn getVendor() [12]u8 {
+    const v = getcpuid(0);
+    @memcpy(@ptrCast([*]u8, &vendor[0]), @ptrCast([*]const u8, &v[1]), 4);
+    @memcpy(@ptrCast([*]u8, &vendor[4]), @ptrCast([*]const u8, &v[3]), 4);
+    @memcpy(@ptrCast([*]u8, &vendor[8]), @ptrCast([*]const u8, &v[2]), 4);
+    std.log.notice("CPU vendor: {}", .{std.mem.span(&vendor)});
+    return vendor;
+}
+
+var name: [48]u8 = undefined;
+pub fn getName() []u8 {
+    var i: u32 = 0x80000002;
+    while(i <= 0x80000004) : (i+=1) {
+        const v = getcpuid(i);
+        @memcpy(@ptrCast([*]u8, &name[(i-0x80000002)*16]), @ptrCast([*]const u8, &v), 16);
+    }
+    std.log.notice("CPU model name: {}", .{std.mem.span(&name)});
+    return std.mem.span(&name);
+}
\ No newline at end of file
diff --git a/kernel/src/arch/x86/x86.zig b/kernel/src/arch/x86/x86.zig
index e69de29..3107aa2 100644
--- a/kernel/src/arch/x86/x86.zig
+++ b/kernel/src/arch/x86/x86.zig
@@ -0,0 +1 @@
+pub const cpuid = @import("cpuid.zig");
\ No newline at end of file
diff --git a/kernel/src/arch/x86_64/x86_64.zig b/kernel/src/arch/x86_64/x86_64.zig
index f4a31e0..9c3e412 100644
--- a/kernel/src/arch/x86_64/x86_64.zig
+++ b/kernel/src/arch/x86_64/x86_64.zig
@@ -1,4 +1,4 @@
-const x86 = @import("src/arch/x86/x86.zig");
+usingnamespace @import("../x86/x86.zig");
 pub const paging = @import("paging.zig");
 pub const interrupt = @import("interrupt.zig");