1/*
  2 * Page management definitions for the Hexagon architecture
  3 *
  4 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 and
  8 * only version 2 as published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 *
 15 * You should have received a copy of the GNU General Public License
 16 * along with this program; if not, write to the Free Software
 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 18 * 02110-1301, USA.
 19 */
 20
 21#ifndef _ASM_PAGE_H
 22#define _ASM_PAGE_H
 23
 24#include <linux/const.h>
 25
 26/*  This is probably not the most graceful way to handle this.  */
 27
 28#ifdef CONFIG_PAGE_SIZE_4KB
 29#define PAGE_SHIFT 12
 30#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_4KB
 31#endif
 32
 33#ifdef CONFIG_PAGE_SIZE_16KB
 34#define PAGE_SHIFT 14
 35#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_16KB
 36#endif
 37
 38#ifdef CONFIG_PAGE_SIZE_64KB
 39#define PAGE_SHIFT 16
 40#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_64KB
 41#endif
 42
 43#ifdef CONFIG_PAGE_SIZE_256KB
 44#define PAGE_SHIFT 18
 45#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_256KB
 46#endif
 47
 48#ifdef CONFIG_PAGE_SIZE_1MB
 49#define PAGE_SHIFT 20
 50#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_1MB
 51#endif
 52
 53/*
 54 *  These should be defined in hugetlb.h, but apparently not.
 55 *  "Huge" for us should be 4MB or 16MB, which are both represented
 56 *  in L1 PTE's.  Right now, it's set up for 4MB.
 57 */
 58#ifdef CONFIG_HUGETLB_PAGE
 59#define HPAGE_SHIFT 22
 60#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
 61#define HPAGE_MASK (~(HPAGE_SIZE-1))
 62#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
 63#define HVM_HUGEPAGE_SIZE 0x5
 64#endif
 65
 66#define PAGE_SIZE  (1UL << PAGE_SHIFT)
 67#define PAGE_MASK  (~((1 << PAGE_SHIFT) - 1))
 68
 69#ifdef __KERNEL__
 70#ifndef __ASSEMBLY__
 71
 72/*
 73 * This is for PFN_DOWN, which mm.h needs.  Seems the right place to pull it in.
 74 */
 75#include <linux/pfn.h>
 76
 77/*
 78 * We implement a two-level architecture-specific page table structure.
 79 * Null intermediate page table level (pmd, pud) definitions will come from
 80 * asm-generic/pagetable-nopmd.h and asm-generic/pagetable-nopud.h
 81 */
 82typedef struct { unsigned long pte; } pte_t;
 83typedef struct { unsigned long pgd; } pgd_t;
 84typedef struct { unsigned long pgprot; } pgprot_t;
 85typedef struct page *pgtable_t;
 86
 87#define pte_val(x)     ((x).pte)
 88#define pgd_val(x)     ((x).pgd)
 89#define pgprot_val(x)  ((x).pgprot)
 90#define __pte(x)       ((pte_t) { (x) })
 91#define __pgd(x)       ((pgd_t) { (x) })
 92#define __pgprot(x)    ((pgprot_t) { (x) })
 93
 94/*
 95 * We need a __pa and a __va routine for kernel space.
 96 * MIPS says they're only used during mem_init.
 97 * also, check if we need a PHYS_OFFSET.
 98 */
 99#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET)
100#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
101
102/* The "page frame" descriptor is defined in linux/mm.h */
103struct page;
104
105/* Returns page frame descriptor for virtual address. */
106#define virt_to_page(kaddr) pfn_to_page(PFN_DOWN(__pa(kaddr)))
107
108/* Default vm area behavior is non-executable.  */
109#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | \
110				VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
111
112#define pfn_valid(pfn) ((pfn) < max_mapnr)
113#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
114
115/*  Need to not use a define for linesize; may move this to another file.  */
116static inline void clear_page(void *page)
117{
118	/*  This can only be done on pages with L1 WB cache */
119	asm volatile(
120		"	loop0(1f,%1);\n"
121		"1:	{ dczeroa(%0);\n"
122		"	  %0 = add(%0,#32); }:endloop0\n"
123		: "+r" (page)
124		: "r" (PAGE_SIZE/32)
125		: "lc0", "sa0", "memory"
126	);
127}
128
129#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)
130
131/*
132 * Under assumption that kernel always "sees" user map...
133 */
134#define clear_user_page(page, vaddr, pg)	clear_page(page)
135#define copy_user_page(to, from, vaddr, pg)	copy_page(to, from)
136
137/*
138 * page_to_phys - convert page to physical address
139 * @page - pointer to page entry in mem_map
140 */
141#define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
142
143/*
144 * For port to Hexagon Virtual Machine, MAYBE we check for attempts
145 * to reference reserved HVM space, but in any case, the VM will be
146 * protected.
147 */
148#define kern_addr_valid(addr)   (1)
149
150#include <asm-generic/memory_model.h>
151/* XXX Todo: implement assembly-optimized version of getorder. */
152#include <asm-generic/getorder.h>
153
154#endif /* ifdef __ASSEMBLY__ */
155#endif /* ifdef __KERNEL__ */
156
157#endif