1 files changed, 347 insertions, 0 deletions
diff --git a/arch/avr32/include/asm/pgtable.h b/arch/avr32/include/asm/pgtable.h
new file mode 100644
index 000000000..358006640
--- /dev/null
+++ b/arch/avr32/include/asm/pgtable.h
@@ -0,0 +1,347 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_PGTABLE_H
+#define __ASM_AVR32_PGTABLE_H
+
+#include <asm/addrspace.h>
+
+#ifndef __ASSEMBLY__
+#include <linux/sched.h>
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * Use two-level page tables just as the i386 (without PAE)
+ */
+#include <asm/pgtable-2level.h>
+
+/*
+ * The following code might need some cleanup when the values are
+ * final...
+ */
+#define PMD_SIZE	(1UL << PMD_SHIFT)
+#define PMD_MASK	(~(PMD_SIZE-1))
+#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
+#define PGDIR_MASK	(~(PGDIR_SIZE-1))
+
+#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
+#define FIRST_USER_ADDRESS	0UL
+
+#ifndef __ASSEMBLY__
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern void paging_init(void);
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used for
+ * zero-mapped memory areas etc.
+ */
+extern struct page *empty_zero_page;
+#define ZERO_PAGE(vaddr) (empty_zero_page)
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 8 MiB value just means that there will be a 8 MiB "hole"
+ * after the uncached physical memory (P2 segment) until the vmalloc
+ * area starts. That means that any out-of-bounds memory accesses will
+ * hopefully be caught; we don't know if the end of the P1/P2 segments
+ * are actually used for anything, but it is anyway safer to let the
+ * MMU catch these kinds of errors than to rely on the memory bus.
+ *
+ * A "hole" of the same size is added to the end of the P3 segment as
+ * well. It might seem wasteful to use 16 MiB of virtual address space
+ * on this, but we do have 512 MiB of it...
+ *
+ * The vmalloc() routines leave a hole of 4 KiB between each vmalloced
+ * area for the same reason.
+ */
+#define VMALLOC_OFFSET	(8 * 1024 * 1024)
+#define VMALLOC_START	(P3SEG + VMALLOC_OFFSET)
+#define VMALLOC_END	(P4SEG - VMALLOC_OFFSET)
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * Page flags. Some of these flags are not directly supported by
+ * hardware, so we have to emulate them.
+ */
+#define _TLBEHI_BIT_VALID	9
+#define _TLBEHI_VALID		(1 << _TLBEHI_BIT_VALID)
+
+#define _PAGE_BIT_WT		0  /* W-bit   : write-through */
+#define _PAGE_BIT_DIRTY		1  /* D-bit   : page changed */
+#define _PAGE_BIT_SZ0		2  /* SZ0-bit : Size of page */
+#define _PAGE_BIT_SZ1		3  /* SZ1-bit : Size of page */
+#define _PAGE_BIT_EXECUTE	4  /* X-bit   : execute access allowed */
+#define _PAGE_BIT_RW		5  /* AP0-bit : write access allowed */
+#define _PAGE_BIT_USER		6  /* AP1-bit : user space access allowed */
+#define _PAGE_BIT_BUFFER	7  /* B-bit   : bufferable */
+#define _PAGE_BIT_GLOBAL	8  /* G-bit   : global (ignore ASID) */
+#define _PAGE_BIT_CACHABLE	9  /* C-bit   : cachable */
+
+/* If we drop support for 1K pages, we get two extra bits */
+#define _PAGE_BIT_PRESENT	10
+#define _PAGE_BIT_ACCESSED	11 /* software: page was accessed */
+
+#define _PAGE_WT		(1 << _PAGE_BIT_WT)
+#define _PAGE_DIRTY		(1 << _PAGE_BIT_DIRTY)
+#define _PAGE_EXECUTE		(1 << _PAGE_BIT_EXECUTE)
+#define _PAGE_RW		(1 << _PAGE_BIT_RW)
+#define _PAGE_USER		(1 << _PAGE_BIT_USER)
+#define _PAGE_BUFFER		(1 << _PAGE_BIT_BUFFER)
+#define _PAGE_GLOBAL		(1 << _PAGE_BIT_GLOBAL)
+#define _PAGE_CACHABLE		(1 << _PAGE_BIT_CACHABLE)
+
+/* Software flags */
+#define _PAGE_ACCESSED		(1 << _PAGE_BIT_ACCESSED)
+#define _PAGE_PRESENT		(1 << _PAGE_BIT_PRESENT)
+
+/*
+ * Page types, i.e. sizes. _PAGE_TYPE_NONE corresponds to what is
+ * usually called _PAGE_PROTNONE on other architectures.
+ *
+ * XXX: Find out if _PAGE_PROTNONE is equivalent with !_PAGE_USER. If
+ * so, we can encode all possible page sizes (although we can't really
+ * support 1K pages anyway due to the _PAGE_PRESENT and _PAGE_ACCESSED
+ * bits)
+ *
+ */
+#define _PAGE_TYPE_MASK		((1 << _PAGE_BIT_SZ0) | (1 << _PAGE_BIT_SZ1))
+#define _PAGE_TYPE_NONE		(0 << _PAGE_BIT_SZ0)
+#define _PAGE_TYPE_SMALL	(1 << _PAGE_BIT_SZ0)
+#define _PAGE_TYPE_MEDIUM	(2 << _PAGE_BIT_SZ0)
+#define _PAGE_TYPE_LARGE	(3 << _PAGE_BIT_SZ0)
+
+/*
+ * Mask which drop software flags. We currently can't handle more than
+ * 512 MiB of physical memory, so we can use bits 29-31 for other
+ * stuff.  With a fixed 4K page size, we can use bits 10-11 as well as
+ * bits 2-3 (SZ)
+ */
+#define _PAGE_FLAGS_HARDWARE_MASK	0xfffff3ff
+
+#define _PAGE_FLAGS_CACHE_MASK	(_PAGE_CACHABLE | _PAGE_BUFFER | _PAGE_WT)
+
+/* Flags that may be modified by software */
+#define _PAGE_CHG_MASK		(PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY \
+				 | _PAGE_FLAGS_CACHE_MASK)
+
+#define _PAGE_FLAGS_READ	(_PAGE_CACHABLE	| _PAGE_BUFFER)
+#define _PAGE_FLAGS_WRITE	(_PAGE_FLAGS_READ | _PAGE_RW | _PAGE_DIRTY)
+
+#define _PAGE_NORMAL(x)	__pgprot((x) | _PAGE_PRESENT | _PAGE_TYPE_SMALL	\
+				 | _PAGE_ACCESSED)
+
+#define PAGE_NONE	(_PAGE_ACCESSED | _PAGE_TYPE_NONE)
+#define PAGE_READ	(_PAGE_FLAGS_READ | _PAGE_USER)
+#define PAGE_EXEC	(_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_USER)
+#define PAGE_WRITE	(_PAGE_FLAGS_WRITE | _PAGE_USER)
+#define PAGE_KERNEL	_PAGE_NORMAL(_PAGE_FLAGS_WRITE | _PAGE_EXECUTE | _PAGE_GLOBAL)
+#define PAGE_KERNEL_RO	_PAGE_NORMAL(_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_GLOBAL)
+
+#define _PAGE_P(x)	_PAGE_NORMAL((x) & ~(_PAGE_RW | _PAGE_DIRTY))
+#define _PAGE_S(x)	_PAGE_NORMAL(x)
+
+#define PAGE_COPY	_PAGE_P(PAGE_WRITE | PAGE_READ)
+#define PAGE_SHARED	_PAGE_S(PAGE_WRITE | PAGE_READ)
+
+#ifndef __ASSEMBLY__
+/*
+ * The hardware supports flags for write- and execute access. Read is
+ * always allowed if the page is loaded into the TLB, so the "-w-",
+ * "--x" and "-wx" mappings are implemented as "rw-", "r-x" and "rwx",
+ * respectively.
+ *
+ * The "---" case is handled by software; the page will simply not be
+ * loaded into the TLB if the page type is _PAGE_TYPE_NONE.
+ */
+
+#define __P000	__pgprot(PAGE_NONE)
+#define __P001	_PAGE_P(PAGE_READ)
+#define __P010	_PAGE_P(PAGE_WRITE)
+#define __P011	_PAGE_P(PAGE_WRITE | PAGE_READ)
+#define __P100	_PAGE_P(PAGE_EXEC)
+#define __P101	_PAGE_P(PAGE_EXEC | PAGE_READ)
+#define __P110	_PAGE_P(PAGE_EXEC | PAGE_WRITE)
+#define __P111	_PAGE_P(PAGE_EXEC | PAGE_WRITE | PAGE_READ)
+
+#define __S000	__pgprot(PAGE_NONE)
+#define __S001	_PAGE_S(PAGE_READ)
+#define __S010	_PAGE_S(PAGE_WRITE)
+#define __S011	_PAGE_S(PAGE_WRITE | PAGE_READ)
+#define __S100	_PAGE_S(PAGE_EXEC)
+#define __S101	_PAGE_S(PAGE_EXEC | PAGE_READ)
+#define __S110	_PAGE_S(PAGE_EXEC | PAGE_WRITE)
+#define __S111	_PAGE_S(PAGE_EXEC | PAGE_WRITE | PAGE_READ)
+
+#define pte_none(x)	(!pte_val(x))
+#define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
+
+#define pte_clear(mm,addr,xp)					\
+	do {							\
+		set_pte_at(mm, addr, xp, __pte(0));		\
+	} while (0)
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static inline int pte_write(pte_t pte)
+{
+	return pte_val(pte) & _PAGE_RW;
+}
+static inline int pte_dirty(pte_t pte)
+{
+	return pte_val(pte) & _PAGE_DIRTY;
+}
+static inline int pte_young(pte_t pte)
+{
+	return pte_val(pte) & _PAGE_ACCESSED;
+}
+static inline int pte_special(pte_t pte)
+{
+	return 0;
+}
+
+/* Mutator functions for PTE bits */
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_RW));
+	return pte;
+}
+static inline pte_t pte_mkclean(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY));
+	return pte;
+}
+static inline pte_t pte_mkold(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED));
+	return pte;
+}
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW));
+	return pte;
+}
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY));
+	return pte;
+}
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+	set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED));
+	return pte;
+}
+static inline pte_t pte_mkspecial(pte_t pte)
+{
+	return pte;
+}
+
+#define pmd_none(x)	(!pmd_val(x))
+#define pmd_present(x)	(pmd_val(x))
+
+static inline void pmd_clear(pmd_t *pmdp)
+{
+	set_pmd(pmdp, __pmd(0));
+}
+
+#define	pmd_bad(x)	(pmd_val(x) & ~PAGE_MASK)
+
+/*
+ * Permanent address of a page. We don't support highmem, so this is
+ * trivial.
+ */
+#define pages_to_mb(x)	((x) >> (20-PAGE_SHIFT))
+#define pte_page(x)	(pfn_to_page(pte_pfn(x)))
+
+/*
+ * Mark the prot value as uncacheable and unbufferable
+ */
+#define pgprot_noncached(prot)						\
+	__pgprot(pgprot_val(prot) & ~(_PAGE_BUFFER | _PAGE_CACHABLE))
+
+/*
+ * Mark the prot value as uncacheable but bufferable
+ */
+#define pgprot_writecombine(prot)					\
+	__pgprot((pgprot_val(prot) & ~_PAGE_CACHABLE) | _PAGE_BUFFER)
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ *
+ * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
+ */
+#define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK)
+			    | pgprot_val(newprot)));
+	return pte;
+}
+
+#define page_pte(page)	page_pte_prot(page, __pgprot(0))
+
+#define pmd_page_vaddr(pmd)	pmd_val(pmd)
+#define pmd_page(pmd)		(virt_to_page(pmd_val(pmd)))
+
+/* to find an entry in a page-table-directory. */
+#define pgd_index(address)	(((address) >> PGDIR_SHIFT)	\
+				 & (PTRS_PER_PGD - 1))
+#define pgd_offset(mm, address)	((mm)->pgd + pgd_index(address))
+
+/* to find an entry in a kernel page-table-directory */
+#define pgd_offset_k(address)	pgd_offset(&init_mm, address)
+
+/* Find an entry in the third-level page table.. */
+#define pte_index(address)				\
+	((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+#define pte_offset(dir, address)					\
+	((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
+#define pte_offset_kernel(dir, address)					\
+	((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
+#define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
+#define pte_unmap(pte)		do { } while (0)
+
+struct vm_area_struct;
+extern void update_mmu_cache(struct vm_area_struct * vma,
+			     unsigned long address, pte_t *ptep);
+
+/*
+ * Encode and decode a swap entry
+ *
+ * Constraints:
+ *   _PAGE_TYPE_* at bits 2-3 (for emulating _PAGE_PROTNONE)
+ *   _PAGE_PRESENT at bit 10
+ *
+ * We encode the type into bits 4-9 and offset into bits 11-31. This
+ * gives us a 21 bits offset, or 2**21 * 4K = 8G usable swap space per
+ * device, and 64 possible types.
+ *
+ * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
+ *       and _PAGE_PROTNONE bits
+ */
+#define __swp_type(x)		(((x).val >> 4) & 0x3f)
+#define __swp_offset(x)		((x).val >> 11)
+#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
+#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x)	((pte_t) { (x).val })
+
+typedef pte_t *pte_addr_t;
+
+#define kern_addr_valid(addr)	(1)
+
+/* No page table caches to initialize (?) */
+#define pgtable_cache_init()	do { } while(0)
+
+#include <asm-generic/pgtable.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_AVR32_PGTABLE_H */