/*	IDENT X-3							    */

/****************************************************************************
*    Copyright 2002 Compaq Information Technologies Group, L.P.
*
*    Compaq and the Compaq logo are trademarks of Compaq Information
*    Technologies Group, L.P. in the U.S. and/or other countries.
*
*    Confidential computer software. Valid license from Compaq required for
*    possession, use or copying. Consistent with FAR 12.211 and 12.212,
*    Commercial Computer Software, Computer Software Documentation, and
*    Technical Data for Commercial Items are licensed to the U.S. Government
*    under vendor's standard commercial license.
*****************************************************************************/

/*
*++
*  FACILITY:
*
*      VMS Executive (LIB)
*
*  ABSTRACT:
*
*  This header file provides the basic set of C inline functions for 
*  accessing PTEs.
*
*  AUTHOR:
*
*      Karen L. Noel
*
*  CREATION DATE:      28-Mar-2000
*
*  MODIFICATION HISTORY:
*
*  X-3		KLN3025		Karen L. Noel		26-Feb-2002
*		o Port PT space to IA64.
*               o Remove inline pragmas. We trust the compiler now.
*
*  X-2		KLN2200		Karen L. Noel		15-Nov-2000
*		Fix nested comments.
*--
*/
/*
  Include any header files we need to make these functions work
*/
#ifndef __PTE_FUNCTIONS_LOADED
#define __PTE_FUNCTIONS_LOADED 1

#ifdef __INITIAL_POINTER_SIZE			 /* Defined whenever ptr size pragmas supported */
#pragma __required_pointer_size __save		 /* Save the previously-defined required ptr size */
#pragma __required_pointer_size __short		 /* And set ptr size default to 32-bit pointers */
#endif

#include <far_pointers.h>
#include <hwrpbdef.h>
#include <ints.h>
#include <ptedef.h>
#include <ssdef.h>
#include <vadef.h>


/* 
*++ 
* $read_pte - Read a PTE
*
* This function reads a PTE.
*
* With VIRBND and SYSPTBR enabled, the level 1 page table page cannot be referenced 
* safely in a virtual manner. This function references the level 1 page table
* physically when necessary.
*
* Input: pte_address - Address of PTE to read
* Output: contents_p - Address to store the contents of the PTE
*--
*/
static void $read_pte (PTE_PQ pte_address, PTE_PQ contents_p)
{
	extern PTE mmg$read_l1pte (PTE_PQ pte_address);
	extern PTE_PQ const mmg$gq_l1_base[VA$C_VRNX_COUNT];
	extern uint64 const mmg$gq_page_size;
	extern uint64 const mmg$gq_bwp_width;
	extern uint64 const mmg$gq_bwp_mask;
	extern HWRPB * exe$gpq_hwrpb;

	/* If this system doesn't support system space page tables */
	/* or, if this isn't a L1 PTE address, just read the PTE   */
	/* Note for IA64, hwprb$v_virbnd == 0 */
	if ((exe$gpq_hwrpb->hwrpb$v_virbnd == 0) ||
	    ((uint64)pte_address < (uint64)mmg$gq_l1_base[VA$C_VRNX_SYSTEM]) ||	    
	    ((uint64)pte_address >= (uint64)mmg$gq_l1_base[VA$C_VRNX_SYSTEM]+mmg$gq_page_size))
	{
		*contents_p = *pte_address;
		return;
	}

	/* Call a macro-32 routine to read the L1PTE physically */
	*contents_p = mmg$read_l1pte(pte_address);
	return;
}
/*+++
* $write_pte - Write to a PTE.
*
* This function write to a PTE.
*
* With VIRBND and SYSPTBR enabled, the level 1 page table page cannot be referenced 
* safely in a virtual manner. This function references the level 1 page table
* physically when necessary.
*
* Input: pte_address - Address of PTE to write
*        contents    - The contents to write to the PTE
*
*---
*/
static void $write_pte (PTE_PQ pte_address, PTE contents)
{
	extern uint64 mmg$write_l1pte (PTE_PQ pte_address, PTE contents);
	extern PTE_PQ const mmg$gq_l1_base[VA$C_VRNX_COUNT];
	extern uint64 const mmg$gq_page_size;
	extern uint64 const mmg$gq_bwp_width;
	extern uint64 const mmg$gq_bwp_mask;
	extern HWRPB * exe$gpq_hwrpb;

	/* If this system doesn't support system space page tables */
	/* or, if this isn't a L1 PTE address, just write the PTE  */
	/* Note for IA64, hwprb$v_virbnd == 0 */
	if ((exe$gpq_hwrpb->hwrpb$v_virbnd == 0) ||
	    ((uint64)pte_address < (uint64)mmg$gq_l1_base[VA$C_VRNX_SYSTEM]) ||	    
	    ((uint64)pte_address >= (uint64)mmg$gq_l1_base[VA$C_VRNX_SYSTEM]+mmg$gq_page_size))
	{
         	*pte_address = contents;
		return;
	}

	/* Call a macro-32 routine to write the L1PTE physically */
	mmg$write_l1pte(pte_address,contents);	
	return;
}

#ifdef __INITIAL_POINTER_SIZE			 /* Defined whenever ptr size pragmas supported */
#pragma __required_pointer_size __restore		 /* Restore the previously-defined required ptr size */
#endif

#endif	/* __PTE_FUNCTIONS_LOADED */