From b15ecd9da581db3563aedad1d660df0dfbbbdba1 Mon Sep 17 00:00:00 2001 From: Bart Trojanowski Date: Sat, 2 Feb 2008 12:21:57 -0500 Subject: [PATCH] X86EMU: handle CPUID instruction This bug is tracked here: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-amd/+bug/180742 After trying to switch from X to VT (or just quit) the video-amd driver attempts to issue INT 10/0 to go to mode 3 (VGA). The emulator, running the BIOS code, would then spit out: c000:0282: A2 ILLEGAL EXTENDED X86 OPCODE! The opcode was 0F A2, or CPUID; it was not implemented in the emulator. This simple patch, against 1.3.0.0, handles the CPUID instruction in one of two ways: 1) if ran on __i386__ then it calls the CPUID instruction directly. 2) if ran elsewhere it returns a canned set of values for function 1. This fix allows the video-amd driver to switch back to console mode, with the GSW BIOS. Thanks to Symbio Technologies for funding my work, and ThinCan for providing hardware :) Signed-off-by: Bart Trojanowski --- hw/xfree86/x86emu/ops2.c | 16 ++++++- hw/xfree86/x86emu/prim_ops.c | 44 ++++++++++++++++++ hw/xfree86/x86emu/x86emu/prim_i386_gcc.h | 71 ++++++++++++++++++++++++++++++ hw/xfree86/x86emu/x86emu/prim_ops.h | 1 + 4 files changed, 131 insertions(+), 1 deletions(-) create mode 100644 hw/xfree86/x86emu/x86emu/prim_i386_gcc.h diff --git a/hw/xfree86/x86emu/ops2.c b/hw/xfree86/x86emu/ops2.c index 8c6c535..324de8a 100644 --- a/hw/xfree86/x86emu/ops2.c +++ b/hw/xfree86/x86emu/ops2.c @@ -328,6 +328,20 @@ static void x86emuOp2_pop_FS(u8 X86EMU_UNUSED(op2)) } /**************************************************************************** +REMARKS: CPUID takes EAX/ECX as inputs, writes EAX/EBX/ECX/EDX as output +Handles opcode 0x0f,0xa2 +****************************************************************************/ +static void x86emuOp2_cpuid(u8 X86EMU_UNUSED(op2)) +{ + START_OF_INSTR(); + DECODE_PRINTF("CPUID\n"); + TRACE_AND_STEP(); + cpuid(); + DECODE_CLEAR_SEGOVR(); + END_OF_INSTR(); +} + +/**************************************************************************** REMARKS: Handles opcode 0x0f,0xa3 ****************************************************************************/ @@ -2734,7 +2748,7 @@ void (*x86emu_optab2[256])(u8) = /* 0xa0 */ x86emuOp2_push_FS, /* 0xa1 */ x86emuOp2_pop_FS, -/* 0xa2 */ x86emuOp2_illegal_op, +/* 0xa2 */ x86emuOp2_cpuid, /* 0xa3 */ x86emuOp2_bt_R, /* 0xa4 */ x86emuOp2_shld_IMM, /* 0xa5 */ x86emuOp2_shld_CL, diff --git a/hw/xfree86/x86emu/prim_ops.c b/hw/xfree86/x86emu/prim_ops.c index 461e09e..e845d1b 100644 --- a/hw/xfree86/x86emu/prim_ops.c +++ b/hw/xfree86/x86emu/prim_ops.c @@ -102,6 +102,12 @@ #define PRIM_OPS_NO_REDEFINE_ASM #include "x86emu/x86emui.h" +#if defined(__GNUC__) +#if defined(__i386__) || defined(__x86_64__) +#include "x86emu/prim_i386_gcc.h" +#endif +#endif + /*------------------------- Global Variables ------------------------------*/ static u32 x86emu_parity_tab[8] = @@ -2654,3 +2660,41 @@ DB( if (CHECK_SP_ACCESS()) return res; } +/**************************************************************************** +REMARKS: +CPUID takes EAX/ECX as inputs, writes EAX/EBX/ECX/EDX as output +****************************************************************************/ +void cpuid (void) +{ + u32 feature = M.x86.R_EAX; +#ifdef prim_cpuid + prim_cpuid(M.x86.R_EAX, M.x86.R_EBX, M.x86.R_ECX, M.x86.R_EDX); +#endif + switch (feature) { + case 0: + M.x86.R_EAX = 1; // maximum function number we support +#ifndef prim_cpuid + M.x86.R_EBX = 0x756e6547; + M.x86.R_ECX = 0x6c65746e; + M.x86.R_EDX = 0x49656e69; +#endif + break; + case 1: +#ifndef prim_cpuid + M.x86.R_EAX = 0x00000480; // 486dx4 + M.x86.R_EBX = 0x00000000; + M.x86.R_ECX = 0x00000000; + M.x86.R_EDX = 0x00000002; // VME +#else + M.x86.R_EDX &= 0x00000012; // TSC and VME +#endif + break; + default: + M.x86.R_EAX = 0; // don't support extended features + M.x86.R_EBX = 0; + M.x86.R_ECX = 0; + M.x86.R_EDX = 0; + break; + } +} + diff --git a/hw/xfree86/x86emu/x86emu/prim_i386_gcc.h b/hw/xfree86/x86emu/x86emu/prim_i386_gcc.h new file mode 100644 index 0000000..408caf7 --- /dev/null +++ b/hw/xfree86/x86emu/x86emu/prim_i386_gcc.h @@ -0,0 +1,71 @@ +/**************************************************************************** +* +* Inline helpers for x86emu +* +* Copyright (C) 2008 Bart Trojanowski, Symbio Technologies, LLC +* +* ======================================================================== +* +* Permission to use, copy, modify, distribute, and sell this software and +* its documentation for any purpose is hereby granted without fee, +* provided that the above copyright notice appear in all copies and that +* both that copyright notice and this permission notice appear in +* supporting documentation, and that the name of the authors not be used +* in advertising or publicity pertaining to distribution of the software +* without specific, written prior permission. The authors makes no +* representations about the suitability of this software for any purpose. +* It is provided "as is" without express or implied warranty. +* +* THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, +* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO +* EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR +* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF +* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR +* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR +* PERFORMANCE OF THIS SOFTWARE. +* +* ======================================================================== +* +* Language: GNU C +* Environment: GCC on i386 or x86-64 +* Developer: Bart Trojanowski +* +* Description: This file defines a few x86 macros that can be used by the +* emulator to execute native instructions. +* +* For PIC vs non-PIC code refer to: +* http://sam.zoy.org/blog/2007-04-13-shlib-with-non-pic-code-have-inline-assembly-and-pic-mix-well +* +****************************************************************************/ +#ifndef __X86EMU_PRIM_I386_GCC_H +#define __X86EMU_PRIM_I386_GCC_H + +#if !defined(__GNUC__) || !(defined(__i386__) || defined(__x86_64__)) +#error This file is intended to be used by gcc on i386 or x86-64 system +#endif + +#ifdef __PIC__ + +#define prim_cpuid(a,b,c,d) \ + __asm__ __volatile__ ("pushl %%ebx \n\t" \ + "cpuid \n\t" \ + "movl %%ebx, %1 \n\t" \ + "popl %%ebx \n\t" \ + : "=a" (a), "=r" (b), \ + "=c" (c), "=d" (d) \ + : "a" (a), "c" (c) \ + : "cc") + +#else // __PIC__ + +#define prim_cpuid(a,b,c,d) \ + __asm__ __volatile__ ("cpuid" \ + : "=a" (a), "=b" (b), \ + "=c" (c), "=d" (d) \ + : "a" (a), "c" (c) \ + : "cc") + +#endif // __PIC__ + + +#endif // __X86EMU_PRIM_I386_GCC_H diff --git a/hw/xfree86/x86emu/x86emu/prim_ops.h b/hw/xfree86/x86emu/x86emu/prim_ops.h index bea8357..6ac2a29 100644 --- a/hw/xfree86/x86emu/x86emu/prim_ops.h +++ b/hw/xfree86/x86emu/x86emu/prim_ops.h @@ -133,6 +133,7 @@ void push_word (u16 w); void push_long (u32 w); u16 pop_word (void); u32 pop_long (void); +void cpuid (void); #ifdef __cplusplus } /* End of "C" linkage for C++ */ -- 1.5.3.7.1150.g149d432