asm {
USE32

SYS_PCIBIOS_SERVICE_DIR:: DU32	0;
SYS_PCI_SERVICES::			 DU32 	0;

SYS_FIND_PCIBIOS_SERVICE_DIR::
				MOV 		ESI,0xE0000
				MOV 		ECX,(0x100000-0xE0000)/4
@@05: 	CMP 		U32 [ESI],'_32_'
				JNE 		@@20
				PUSH		ECX
				XOR 		ECX,ECX
				MOV 		CL,U8 9[ESI]
				SHL 		ECX,4
@@10: 	MOV 		EDI,ESI
				XOR 		EAX,EAX
				XOR 		EDX,EDX
@@15: 	MOV 		DL,U8 [EDI]
				ADD 		EAX,EDX
				INC 		EDI
				DEC 		ECX
				JNZ 		@@15
				POP 		ECX
				TEST		AL,AL
				JNZ 		@@20
				MOV 		U32 [SYS_PCIBIOS_SERVICE_DIR],ESI
				MOV 		ESI,U32 4[ESI]
				MOV 		U32 [SYS_PCIBIOS_SERVICE_CALL],ESI
				RET

@@20: 	ADD 		ESI,4
				LOOP		@@05
				MOV 		U32 [SYS_PCIBIOS_SERVICE_DIR],0
				RET

SYS_FIND_PCI_SERVICES::
				MOV 		ESI,U32 [SYS_PCIBIOS_SERVICE_DIR]
				TEST		ESI,ESI
				JNZ 		@@05
				MOV 		U32 [SYS_PCI_SERVICES],0
				RET
@@05: 	MOV 		EAX,'$$PCI'
				XOR 		EBX,EBX
				DU8 		0x9A; 					 //CALL CGDT.cs32:PCIBIOS_SERVICE
SYS_PCIBIOS_SERVICE_CALL:: DU32 0;
				DU16		CGDT.cs32;
				TEST		AL,AL
				JNZ 		@@05
				LEA 		ESI,U32 [EBX+EDX]
				MOV 		U32 [SYS_PCI_SERVICES],ESI
				RET

@@05: 	MOV 		U32 [SYS_PCI_SERVICES],0
				RET

USE64
C32_EAX:: 			DU32		0;
C32_EBX:: 			DU32		0;
C32_ECX:: 			DU32		0;
C32_EDX:: 			DU32		0;
C32_ESI:: 			DU32		0;
C32_EDI:: 			DU32		0;
C32_EFLAGS::		DU32		0;

C32_RSP:: 			DU64		0;

_FAR_CALL32::
//This calls a 32-bit mode routine.
//(We must switch from 64-bit mode to do it.)
//
//NON REENTRANT
//
				PUSH		RBP
				MOV 		RBP,RSP
				MOV 		RAX,U64 SF_ARG1[RBP]
				TEST		RAX,RAX
				JNZ 		@@05
				POP 		RBP
				RET1		8 			//return FALSE
@@05: 	MOV 		U32 [C32_ADD],EAX
				PUSH_REGS
				PUSHFD
				XOR 		RAX,RAX
				PUSH		U64 FS:CTask.addr[RAX]
				PUSH		U64 GS:CCPU.addr[RAX]
				MOV 		U64 [C32_RSP],RSP
				PUSH		U32 CGDT.ds 						//STACKSEG
				PUSH		U32 BOOT_RAM_LIMIT			//STACK
				PUSH		U32 0 									//FLAGS--interrupts off
				PUSH		U32 CGDT.cs32
				LEA 		RAX,[@@15]
				PUSH		RAX
				IRET
USE32
@@15:
				WBINVD
//disable paging
				MOV_EAX_CR0
				BTR 		EAX,CR0f_PG
				MOV_CR0_EAX

				MOV 		ECX,IA32_EFER
				XOR 		EDX,EDX
				XOR 		EAX,EAX
				WRMSR

				MOV 		AX,CGDT.ds
				MOV 		FS,AX
				MOV 		GS,AX
//SS already set

				MOV 		EAX,U32 [C32_EAX]
				MOV 		EBX,U32 [C32_EBX]
				MOV 		ECX,U32 [C32_ECX]
				MOV 		EDX,U32 [C32_EDX]
				MOV 		ESI,U32 [C32_ESI]
				MOV 		EDI,U32 [C32_EDI]
				MOV 		U32 [C32_EFLAGS],0

				DU8 		0x9A; 					 //CALL CGDT.cs32:[C32_ADD]
C32_ADD:: DU32	0;
				DU16		CGDT.cs32;

				PUSHFD
				POP 		U32 [C32_EFLAGS]

				MOV 		U32 [C32_EAX],EAX
				MOV 		U32 [C32_EBX],EBX
				MOV 		U32 [C32_ECX],ECX
				MOV 		U32 [C32_EDX],EDX
				MOV 		U32 [C32_ESI],ESI
				MOV 		U32 [C32_EDI],EDI

				PUSH		U32 0 	//Return from next call will be 64-bit
				CALL		SYS_ENTER_LONG_MODE

USE64 	MOV 		RSP,U64 [C32_RSP]
				POP 		RAX
				CALL		SET_GS_BASE
				POP 		RAX
				CALL		SET_FS_BASE

				POPFD
				POP_REGS
				XOR 		RAX,RAX
				MOV 		AL,TRUE
				POP 		RBP
				RET1		8
}

_extern C32_EAX U32 c32_eax;
_extern C32_EBX U32 c32_ebx;
_extern C32_ECX U32 c32_ecx;
_extern C32_EDX U32 c32_edx;
_extern C32_ESI U32 c32_esi;
_extern C32_EDI U32 c32_edi;
_extern C32_EFLAGS U32 c32_eflags;
_extern SYS_PCI_SERVICES U32 sys_pci_services;

_extern _FAR_CALL32 Bool FarCall32(U0 (*fp_addr)());//Not reentrant.For PCIBIOS.

U8 PCIReadU8(I64 bus,I64 dev,I64 fun,I64 rg)
{//Read U8 in PCI configspace at bus,dev,fun,reg.
	I64 res;
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB108;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	if (FarCall32(sys_pci_services))
		res=c32_ecx.u8[0];
	else
		res=0xFF;
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
	return res;
}

U16 PCIReadU16(I64 bus,I64 dev,I64 fun,I64 rg)
{//Read U16 in PCI configspace at bus,dev,fun,reg.
	I64 res;
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB109;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	if (FarCall32(sys_pci_services))
		res=c32_ecx.u16[0];
	else
		res=0xFFFF;
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
	return res;
}

U32 PCIReadU32(I64 bus,I64 dev,I64 fun,I64 rg)
{//Read U32 in PCI configspace at bus,dev,fun,reg.
	I64 res;
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB10A;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	if (FarCall32(sys_pci_services))
		res=c32_ecx;
	else
		res=0xFFFFFFFF;
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
	return res;
}

U0 PCIWriteU8(I64 bus,I64 dev,I64 fun,I64 rg,I64 val)
{//Write U8 in PCI configspace at bus,dev,fun,reg.
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB10B;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	c32_ecx=val;
	FarCall32(sys_pci_services);
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
}

U0 PCIWriteU16(I64 bus,I64 dev,I64 fun,I64 rg,I64 val)
{//Write U16 in PCI configspace at bus,dev,fun,reg.
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB10C;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	c32_ecx=val;
	FarCall32(sys_pci_services);
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
}

U0 PCIWriteU32(I64 bus,I64 dev,I64 fun,I64 rg,I64 val)
{//Write U32 in PCI configspace at bus,dev,fun,reg.
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB10D;
	c32_ebx=bus<<8+dev<<3+fun;
	c32_edi=rg;
	c32_ecx=val;
	FarCall32(sys_pci_services);
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
}

I64 PCIClassFind(I64 class_code,I64 n)
{/*Find bus,dev,fun of Nth class_code dev.

class_code is low three bytes
n is index starting at zero
Return: -1 not found
else bus,dev,fun.
*/
	I64 res;
	PUSHFD
	CLI
	while (LBts(&sys_semas[SEMA_FAR_CALL32],0))
		Yield;
	c32_eax=0xB103;
	c32_esi=n;
	c32_ecx=class_code;
	if (FarCall32(sys_pci_services) && !c32_eax.u8[1])
		res=c32_ebx.u8[1]<<16+(c32_ebx&0xF8)<<5+c32_ebx&7;
	else
		res=-1;
	LBtr(&sys_semas[SEMA_FAR_CALL32],0);
	POPFD
	return res;
}