/*
* Hexagon VM page table entry definitions
*
* Copyright (c) 2010-2011,2013 The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/

#ifndef _ASM_VM_MMU_H
#define _ASM_VM_MMU_H

/*
* Shift, mask, and other constants for the Hexagon Virtual Machine
* page tables.
*
* Virtual machine MMU allows first-level entries to either be
* single-level lookup PTEs for very large pages, or PDEs pointing
* to second-level PTEs for smaller pages. If PTE is single-level,
* the least significant bits cannot be used as software bits to encode
* virtual memory subsystem information about the page, and that state
* must be maintained in some parallel data structure.
*/

/* S or Page Size field in PDE */
#define __HVM_PDE_S (0x7 << 0)
#define __HVM_PDE_S_4KB 0
#define __HVM_PDE_S_16KB 1
#define __HVM_PDE_S_64KB 2
#define __HVM_PDE_S_256KB 3
#define __HVM_PDE_S_1MB 4
#define __HVM_PDE_S_4MB 5
#define __HVM_PDE_S_16MB 6
#define __HVM_PDE_S_INVALID 7

/* Masks for L2 page table pointer, as function of page size */
#define __HVM_PDE_PTMASK_4KB 0xfffff000
#define __HVM_PDE_PTMASK_16KB 0xfffffc00
#define __HVM_PDE_PTMASK_64KB 0xffffff00
#define __HVM_PDE_PTMASK_256KB 0xffffffc0
#define __HVM_PDE_PTMASK_1MB 0xfffffff0

/*
* Virtual Machine PTE Bits/Fields
*/
#define __HVM_PTE_T (1<<4)
#define __HVM_PTE_U (1<<5)
#define __HVM_PTE_C (0x7<<6)
#define __HVM_PTE_CVAL(pte) (((pte) & __HVM_PTE_C) >> 6)
#define __HVM_PTE_R (1<<9)
#define __HVM_PTE_W (1<<10)
#define __HVM_PTE_X (1<<11)

/*
* Cache Attributes, to be shifted as necessary for virtual/physical PTEs
*/

#define __HEXAGON_C_WB 0x0 /* Write-back, no L2 */
#define __HEXAGON_C_WT 0x1 /* Write-through, no L2 */
#define __HEXAGON_C_UNC 0x6 /* Uncached memory */
#if CONFIG_HEXAGON_ARCH_VERSION >= 2
#define __HEXAGON_C_DEV 0x4 /* Device register space */
#else
#define __HEXAGON_C_DEV __HEXAGON_C_UNC
#endif
#define __HEXAGON_C_WT_L2 0x5 /* Write-through, with L2 */
#define __HEXAGON_C_WB_L2 0x7 /* Write-back, with L2 */

/*
* This can be overriden, but we're defaulting to the most aggressive
* cache policy, the better to find bugs sooner.
*/

#define CACHE_DEFAULT __HEXAGON_C_WB_L2

/* Masks for physical page address, as a function of page size */

#define __HVM_PTE_PGMASK_4KB 0xfffff000
#define __HVM_PTE_PGMASK_16KB 0xffffc000
#define __HVM_PTE_PGMASK_64KB 0xffff0000
#define __HVM_PTE_PGMASK_256KB 0xfffc0000
#define __HVM_PTE_PGMASK_1MB 0xfff00000

/* Masks for single-level large page lookups */

#define __HVM_PTE_PGMASK_4MB 0xffc00000
#define __HVM_PTE_PGMASK_16MB 0xff000000

/*
* "Big kernel page mappings" (see vm_init_segtable.S)
* are currently 16MB
*/

#define BIG_KERNEL_PAGE_SHIFT 24
#define BIG_KERNEL_PAGE_SIZE (1 << BIG_KERNEL_PAGE_SHIFT)



#endif /* _ASM_VM_MMU_H */