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/*
* Copyright (c) 2006-2008 Advanced Micro Devices,Inc. ("AMD").
*
* 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.
*
* This code 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
*/
//* Function: *
//* Handles trapped and virtualized I/O
#include "VSA2.H"
#include "PROTOS.H"
#include "SYSMGR.H"
// External variables
extern ULONG Saved_EAX, Saved_EDI;
extern ULONG Nested_EAX, Nested_EDI;
extern Descriptor Saved_ES, Flat_Descriptor;
extern SmiHeader SMM_Header;
// External routines
extern void pascal write_flat_size(ULONG, ULONG, UCHAR);
extern ULONG pascal Convert_To_Physical_Addr(ULONG);
#define PAGING_ENABLED 0x80000001
#define ADDR32 1
#define DATA32 2
typedef struct {
union {
ULONG Ulong;
struct {
USHORT LowAddr;
UCHAR MidAddr;
UCHAR HiAddr;
};
};
} DESCR;
//***********************************************************************
// Returns the physical address of the location to return the value
//***********************************************************************
ULONG pascal Get_Logical_Address(SmiHeader * SmiHdr, ULONG * CR0_Ptr)
{ UCHAR Override = 0, Size, Instruction;
static UCHAR SizeToIncr[16] = {0,1,0,2,0,0,0,0,0,0,0,0,0,0,0,4};
ULONG EDI, Logical_Addr, Incr, Phys_Addr, Reg_Ptr;
register Descriptor * Callers_ES;
DESCR Mem_Ptr;
Size = (UCHAR)SmiHdr->data_size;
if (SmiHdr == &SMM_Header) {
Reg_Ptr = SysMgr_VSM + (ULONG)((USHORT)&Saved_EAX);
// Get ES:EDI in case it's INSW
Callers_ES = &Saved_ES;
EDI = Saved_EDI;
} else {
// Nested_EAX is a flat ptr to EAX on the VSM's stack
Reg_Ptr = Nested_EAX;
// Get ES:EDI in case it's INSW
Callers_ES = &Flat_Descriptor;
EDI = Nested_EDI;
}
// Determine default operand and address size
if (Callers_ES->attr & D_BIT) {
Override = DATA32 | ADDR32;
}
// Get address of trapped code
Logical_Addr = SmiHdr->Current_EIP + SmiHdr->_CS.base;
do {
// If paging is enabled...
if ((SmiHdr->r_CR0 & PAGING_ENABLED) == PAGING_ENABLED){
// translate logical to physical address via the page tables
Phys_Addr = Convert_To_Physical_Addr(Logical_Addr);
} else {
Phys_Addr = Logical_Addr;
}
// Get opcode
Instruction = (UCHAR)read_flat(Phys_Addr);
switch (Instruction) {
case 0xE4: // IN AL, <nn>
case 0xE5: // IN AX, <nn>
case 0xEC: // IN AL, DX
case 0xED: // IN AX, DX
*CR0_Ptr = 0x00000000;
return Reg_Ptr;
case 0x67: // Address Size
Override ^= ADDR32;
break;
case 0x66: // Data Size
// Override ^= DATA32;
case 0xF2: // REPNE
case 0xF3: // REPE
break;
case 0x6C: // INSB
case 0x6D: // INSW/INSD
Mem_Ptr.LowAddr = Callers_ES->base_15_0;
Mem_Ptr.MidAddr = Callers_ES->base_23_16;
Mem_Ptr.HiAddr = Callers_ES->base_31_24;
// (E)DI has already been inc'd/dec'd
Incr = SizeToIncr[Size];
if (SmiHdr->EFLAGS & EFLAGS_DF) {
EDI += Incr;
} else {
EDI -= Incr;
}
// If 16-bit mode, mask 16 MSBs of ptr
if (!(Override & ADDR32)) {
EDI &= 0x0000FFFF;
}
Mem_Ptr.Ulong += EDI;
*CR0_Ptr = SmiHdr->r_CR0;
return Mem_Ptr.Ulong;
default:
// Unexpected opcode
Log_Error("Unexpected opcode at 0x%08X = 0x%08X", Phys_Addr, read_flat(Phys_Addr));
return 0xFFFFFFFF;
}
// Increment code ptr
Logical_Addr++;
} while (1);
}
//***********************************************************************
// Returns an I/O value to AL/AX/EAX or ES:(E)DI
//***********************************************************************
void pascal Return_Virtual_Value(SmiHeader * SmiHdr, ULONG Data)
{ ULONG PhysicalAddr, LogicalAddr, CR0;
UCHAR Size;
LogicalAddr = Get_Logical_Address(SmiHdr, &CR0);
if (LogicalAddr == 0xFFFFFFFF)
return;
Size = (UCHAR)SmiHdr->data_size;
if ((CR0 & PAGING_ENABLED) == PAGING_ENABLED){
// If paging is enabled, translate logical to physical address and
// write one byte at a time since buffer could cross page boundary.
do {
PhysicalAddr = Convert_To_Physical_Addr(LogicalAddr++);
write_flat_size(PhysicalAddr, Data, BYTE_IO);
Data >>= 8;
Size >>= 1;
} while (Size);
} else {
// Write the data to memory
write_flat_size(LogicalAddr, Data, Size);
}
}
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