{ This file is part of the PTCPas framebuffer library Copyright (C) 2001-2010 Nikolay Nikolov (nickysn@users.sourceforge.net) This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version with the following modification: As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules,and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA } {$MODE objfpc} {$ASMMODE intel} {$GOTO on} unit timeunit; interface type TGetClockTics = function: QWord; var TimerResolution: Double; CPS: Double; GetClockTics: TGetClockTics; implementation var UseRDTSC: Boolean; Clk1Lo, Clk1Hi, Clk2Lo, Clk2Hi: DWord; Clk1, Clk2: QWord; ClkDelta: QWord; CpuFlags: DWord; function GetClockTics_RDTSC: QWord; Assembler; Asm rdtsc end; function GetClockTics_LAME: QWord; begin GetClockTics_LAME := MemL[$46C]; end; procedure DetectCPUSpeed_RDTSC; begin {word absolute $46C} Asm mov di, fs:[046Ch] @@1: cmp di, fs:[046Ch] je @@1 rdtsc mov ebx, eax mov ecx, edx mov di, fs:[046Ch] @@2: mov ax, fs:[046Ch] sub ax, di cmp ax, 32 jb @@2 rdtsc mov [Clk1Lo], ebx mov [Clk1Hi], ecx mov [Clk2Lo], eax mov [Clk2Hi], edx end ['EAX','EBX','ECX','EDX','EDI']; { Clk1 := Clk1Lo or (QWord(Clk1Hi) shl 32); Clk2 := Clk2Lo or (QWord(Clk2Hi) shl 32);} Clk1 := Clk1Hi; Clk1 := Clk1 shl 32; Clk1 := Clk1 + Clk1Lo; Clk2 := Clk2Hi; Clk2 := Clk2 shl 32; Clk2 := Clk2 + Clk2Lo; ClkDelta := Clk2 - Clk1; CPS := (ClkDelta * 18.2) / 32; TimerResolution := 1 / CPS; end; procedure _CPU; Assembler; Label nocpuid; Asm mov CpuFlags, 0 pushf pop eax mov ecx, eax xor eax, 40000h push eax popf pushf pop eax xor eax, ecx jz nocpuid push ecx popf mov eax, ecx xor eax, 200000h push eax popf pushf pop eax xor eax, ecx je nocpuid pusha mov eax, 1 cpuid mov CpuFlags, edx popa nocpuid: end; procedure DetectCPU; begin _CPU; if (CpuFlags and $10) <> 0 then UseRDTSC := True else UseRDTSC := False; if UseRDTSC then begin DetectCPUSpeed_RDTSC; GetClockTics := @GetClockTics_RDTSC; end else begin TimerResolution := 1 / 18.2; GetClockTics := @GetClockTics_LAME; end; end; initialization begin DetectCPU; end; end.