[ARM] move include/asm-arm to arch/arm/include/asm

Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 401 insertions, 0 deletions

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
new file mode 100644
index 00000000000..8ab060a53ab
--- /dev/null
+++ b/arch/arm/include/asm/pgtable.h
@@ -0,0 +1,401 @@
+/*
+ *  arch/arm/include/asm/pgtable.h
+ *
+ *  Copyright (C) 1995-2002 Russell King
+ *
+ * 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 _ASMARM_PGTABLE_H
+#define _ASMARM_PGTABLE_H
+
+#include <asm-generic/4level-fixup.h>
+#include <asm/proc-fns.h>
+
+#ifndef CONFIG_MMU
+
+#include "pgtable-nommu.h"
+
+#else
+
+#include <asm/memory.h>
+#include <asm/arch/vmalloc.h>
+#include <asm/pgtable-hwdef.h>
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 8MB value just means that there will be a 8MB "hole" after the
+ * physical memory until the kernel virtual memory starts.  That means that
+ * any out-of-bounds memory accesses will hopefully be caught.
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;)
+ *
+ * Note that platforms may override VMALLOC_START, but they must provide
+ * VMALLOC_END.  VMALLOC_END defines the (exclusive) limit of this space,
+ * which may not overlap IO space.
+ */
+#ifndef VMALLOC_START
+#define VMALLOC_OFFSET		(8*1024*1024)
+#define VMALLOC_START		(((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
+#endif
+
+/*
+ * Hardware-wise, we have a two level page table structure, where the first
+ * level has 4096 entries, and the second level has 256 entries.  Each entry
+ * is one 32-bit word.  Most of the bits in the second level entry are used
+ * by hardware, and there aren't any "accessed" and "dirty" bits.
+ *
+ * Linux on the other hand has a three level page table structure, which can
+ * be wrapped to fit a two level page table structure easily - using the PGD
+ * and PTE only.  However, Linux also expects one "PTE" table per page, and
+ * at least a "dirty" bit.
+ *
+ * Therefore, we tweak the implementation slightly - we tell Linux that we
+ * have 2048 entries in the first level, each of which is 8 bytes (iow, two
+ * hardware pointers to the second level.)  The second level contains two
+ * hardware PTE tables arranged contiguously, followed by Linux versions
+ * which contain the state information Linux needs.  We, therefore, end up
+ * with 512 entries in the "PTE" level.
+ *
+ * This leads to the page tables having the following layout:
+ *
+ *    pgd             pte
+ * |        |
+ * +--------+ +0
+ * |        |-----> +------------+ +0
+ * +- - - - + +4    |  h/w pt 0  |
+ * |        |-----> +------------+ +1024
+ * +--------+ +8    |  h/w pt 1  |
+ * |        |       +------------+ +2048
+ * +- - - - +       | Linux pt 0 |
+ * |        |       +------------+ +3072
+ * +--------+       | Linux pt 1 |
+ * |        |       +------------+ +4096
+ *
+ * See L_PTE_xxx below for definitions of bits in the "Linux pt", and
+ * PTE_xxx for definitions of bits appearing in the "h/w pt".
+ *
+ * PMD_xxx definitions refer to bits in the first level page table.
+ *
+ * The "dirty" bit is emulated by only granting hardware write permission
+ * iff the page is marked "writable" and "dirty" in the Linux PTE.  This
+ * means that a write to a clean page will cause a permission fault, and
+ * the Linux MM layer will mark the page dirty via handle_pte_fault().
+ * For the hardware to notice the permission change, the TLB entry must
+ * be flushed, and ptep_set_access_flags() does that for us.
+ *
+ * The "accessed" or "young" bit is emulated by a similar method; we only
+ * allow accesses to the page if the "young" bit is set.  Accesses to the
+ * page will cause a fault, and handle_pte_fault() will set the young bit
+ * for us as long as the page is marked present in the corresponding Linux
+ * PTE entry.  Again, ptep_set_access_flags() will ensure that the TLB is
+ * up to date.
+ *
+ * However, when the "young" bit is cleared, we deny access to the page
+ * by clearing the hardware PTE.  Currently Linux does not flush the TLB
+ * for us in this case, which means the TLB will retain the transation
+ * until either the TLB entry is evicted under pressure, or a context
+ * switch which changes the user space mapping occurs.
+ */
+#define PTRS_PER_PTE		512
+#define PTRS_PER_PMD		1
+#define PTRS_PER_PGD		2048
+
+/*
+ * PMD_SHIFT determines the size of the area a second-level page table can map
+ * PGDIR_SHIFT determines what a third-level page table entry can map
+ */
+#define PMD_SHIFT		21
+#define PGDIR_SHIFT		21
+
+#define LIBRARY_TEXT_START	0x0c000000
+
+#ifndef __ASSEMBLY__
+extern void __pte_error(const char *file, int line, unsigned long val);
+extern void __pmd_error(const char *file, int line, unsigned long val);
+extern void __pgd_error(const char *file, int line, unsigned long val);
+
+#define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte_val(pte))
+#define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd_val(pmd))
+#define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd_val(pgd))
+#endif /* !__ASSEMBLY__ */
+
+#define PMD_SIZE		(1UL << PMD_SHIFT)
+#define PMD_MASK		(~(PMD_SIZE-1))
+#define PGDIR_SIZE		(1UL << PGDIR_SHIFT)
+#define PGDIR_MASK		(~(PGDIR_SIZE-1))
+
+/*
+ * This is the lowest virtual address we can permit any user space
+ * mapping to be mapped at.  This is particularly important for
+ * non-high vector CPUs.
+ */
+#define FIRST_USER_ADDRESS	PAGE_SIZE
+
+#define FIRST_USER_PGD_NR	1
+#define USER_PTRS_PER_PGD	((TASK_SIZE/PGDIR_SIZE) - FIRST_USER_PGD_NR)
+
+/*
+ * section address mask and size definitions.
+ */
+#define SECTION_SHIFT		20
+#define SECTION_SIZE		(1UL << SECTION_SHIFT)
+#define SECTION_MASK		(~(SECTION_SIZE-1))
+
+/*
+ * ARMv6 supersection address mask and size definitions.
+ */
+#define SUPERSECTION_SHIFT	24
+#define SUPERSECTION_SIZE	(1UL << SUPERSECTION_SHIFT)
+#define SUPERSECTION_MASK	(~(SUPERSECTION_SIZE-1))
+
+/*
+ * "Linux" PTE definitions.
+ *
+ * We keep two sets of PTEs - the hardware and the linux version.
+ * This allows greater flexibility in the way we map the Linux bits
+ * onto the hardware tables, and allows us to have YOUNG and DIRTY
+ * bits.
+ *
+ * The PTE table pointer refers to the hardware entries; the "Linux"
+ * entries are stored 1024 bytes below.
+ */
+#define L_PTE_PRESENT		(1 << 0)
+#define L_PTE_FILE		(1 << 1)	/* only when !PRESENT */
+#define L_PTE_YOUNG		(1 << 1)
+#define L_PTE_BUFFERABLE	(1 << 2)	/* matches PTE */
+#define L_PTE_CACHEABLE		(1 << 3)	/* matches PTE */
+#define L_PTE_USER		(1 << 4)
+#define L_PTE_WRITE		(1 << 5)
+#define L_PTE_EXEC		(1 << 6)
+#define L_PTE_DIRTY		(1 << 7)
+#define L_PTE_SHARED		(1 << 10)	/* shared(v6), coherent(xsc3) */
+
+#ifndef __ASSEMBLY__
+
+/*
+ * The pgprot_* and protection_map entries will be fixed up in runtime
+ * to include the cachable and bufferable bits based on memory policy,
+ * as well as any architecture dependent bits like global/ASID and SMP
+ * shared mapping bits.
+ */
+#define _L_PTE_DEFAULT	L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_CACHEABLE | L_PTE_BUFFERABLE
+#define _L_PTE_READ	L_PTE_USER | L_PTE_EXEC
+
+extern pgprot_t		pgprot_user;
+extern pgprot_t		pgprot_kernel;
+
+#define PAGE_NONE	pgprot_user
+#define PAGE_COPY	__pgprot(pgprot_val(pgprot_user) | _L_PTE_READ)
+#define PAGE_SHARED	__pgprot(pgprot_val(pgprot_user) | _L_PTE_READ | \
+				 L_PTE_WRITE)
+#define PAGE_READONLY	__pgprot(pgprot_val(pgprot_user) | _L_PTE_READ)
+#define PAGE_KERNEL	pgprot_kernel
+
+#define __PAGE_NONE	__pgprot(_L_PTE_DEFAULT)
+#define __PAGE_COPY	__pgprot(_L_PTE_DEFAULT | _L_PTE_READ)
+#define __PAGE_SHARED	__pgprot(_L_PTE_DEFAULT | _L_PTE_READ | L_PTE_WRITE)
+#define __PAGE_READONLY	__pgprot(_L_PTE_DEFAULT | _L_PTE_READ)
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * The table below defines the page protection levels that we insert into our
+ * Linux page table version.  These get translated into the best that the
+ * architecture can perform.  Note that on most ARM hardware:
+ *  1) We cannot do execute protection
+ *  2) If we could do execute protection, then read is implied
+ *  3) write implies read permissions
+ */
+#define __P000  __PAGE_NONE
+#define __P001  __PAGE_READONLY
+#define __P010  __PAGE_COPY
+#define __P011  __PAGE_COPY
+#define __P100  __PAGE_READONLY
+#define __P101  __PAGE_READONLY
+#define __P110  __PAGE_COPY
+#define __P111  __PAGE_COPY
+
+#define __S000  __PAGE_NONE
+#define __S001  __PAGE_READONLY
+#define __S010  __PAGE_SHARED
+#define __S011  __PAGE_SHARED
+#define __S100  __PAGE_READONLY
+#define __S101  __PAGE_READONLY
+#define __S110  __PAGE_SHARED
+#define __S111  __PAGE_SHARED
+
+#ifndef __ASSEMBLY__
+/*
+ * 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)
+
+#define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
+#define pfn_pte(pfn,prot)	(__pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+
+#define pte_none(pte)		(!pte_val(pte))
+#define pte_clear(mm,addr,ptep)	set_pte_ext(ptep, __pte(0), 0)
+#define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
+#define pte_offset_kernel(dir,addr)	(pmd_page_vaddr(*(dir)) + __pte_index(addr))
+#define pte_offset_map(dir,addr)	(pmd_page_vaddr(*(dir)) + __pte_index(addr))
+#define pte_offset_map_nested(dir,addr)	(pmd_page_vaddr(*(dir)) + __pte_index(addr))
+#define pte_unmap(pte)		do { } while (0)
+#define pte_unmap_nested(pte)	do { } while (0)
+
+#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
+
+#define set_pte_at(mm,addr,ptep,pteval) do { \
+	set_pte_ext(ptep, pteval, (addr) >= TASK_SIZE ? 0 : PTE_EXT_NG); \
+ } while (0)
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+#define pte_present(pte)	(pte_val(pte) & L_PTE_PRESENT)
+#define pte_write(pte)		(pte_val(pte) & L_PTE_WRITE)
+#define pte_dirty(pte)		(pte_val(pte) & L_PTE_DIRTY)
+#define pte_young(pte)		(pte_val(pte) & L_PTE_YOUNG)
+#define pte_special(pte)	(0)
+
+/*
+ * The following only works if pte_present() is not true.
+ */
+#define pte_file(pte)		(pte_val(pte) & L_PTE_FILE)
+#define pte_to_pgoff(x)		(pte_val(x) >> 2)
+#define pgoff_to_pte(x)		__pte(((x) << 2) | L_PTE_FILE)
+
+#define PTE_FILE_MAX_BITS	30
+
+#define PTE_BIT_FUNC(fn,op) \
+static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
+
+PTE_BIT_FUNC(wrprotect, &= ~L_PTE_WRITE);
+PTE_BIT_FUNC(mkwrite,   |= L_PTE_WRITE);
+PTE_BIT_FUNC(mkclean,   &= ~L_PTE_DIRTY);
+PTE_BIT_FUNC(mkdirty,   |= L_PTE_DIRTY);
+PTE_BIT_FUNC(mkold,     &= ~L_PTE_YOUNG);
+PTE_BIT_FUNC(mkyoung,   |= L_PTE_YOUNG);
+
+static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
+
+/*
+ * Mark the prot value as uncacheable and unbufferable.
+ */
+#define pgprot_noncached(prot)	__pgprot(pgprot_val(prot) & ~(L_PTE_CACHEABLE | L_PTE_BUFFERABLE))
+#define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~L_PTE_CACHEABLE)
+
+#define pmd_none(pmd)		(!pmd_val(pmd))
+#define pmd_present(pmd)	(pmd_val(pmd))
+#define pmd_bad(pmd)		(pmd_val(pmd) & 2)
+
+#define copy_pmd(pmdpd,pmdps)		\
+	do {				\
+		pmdpd[0] = pmdps[0];	\
+		pmdpd[1] = pmdps[1];	\
+		flush_pmd_entry(pmdpd);	\
+	} while (0)
+
+#define pmd_clear(pmdp)			\
+	do {				\
+		pmdp[0] = __pmd(0);	\
+		pmdp[1] = __pmd(0);	\
+		clean_pmd_entry(pmdp);	\
+	} while (0)
+
+static inline pte_t *pmd_page_vaddr(pmd_t pmd)
+{
+	unsigned long ptr;
+
+	ptr = pmd_val(pmd) & ~(PTRS_PER_PTE * sizeof(void *) - 1);
+	ptr += PTRS_PER_PTE * sizeof(void *);
+
+	return __va(ptr);
+}
+
+#define pmd_page(pmd) virt_to_page(__va(pmd_val(pmd)))
+
+/*
+ * Permanent address of a page. We never have highmem, so this is trivial.
+ */
+#define pages_to_mb(x)		((x) >> (20 - PAGE_SHIFT))
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+#define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
+
+/*
+ * The "pgd_xxx()" functions here are trivial for a folded two-level
+ * setup: the pgd is never bad, and a pmd always exists (as it's folded
+ * into the pgd entry)
+ */
+#define pgd_none(pgd)		(0)
+#define pgd_bad(pgd)		(0)
+#define pgd_present(pgd)	(1)
+#define pgd_clear(pgdp)		do { } while (0)
+#define set_pgd(pgd,pgdp)	do { } while (0)
+
+/* to find an entry in a page-table-directory */
+#define pgd_index(addr)		((addr) >> PGDIR_SHIFT)
+
+#define pgd_offset(mm, addr)	((mm)->pgd+pgd_index(addr))
+
+/* to find an entry in a kernel page-table-directory */
+#define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
+
+/* Find an entry in the second-level page table.. */
+#define pmd_offset(dir, addr)	((pmd_t *)(dir))
+
+/* Find an entry in the third-level page table.. */
+#define __pte_index(addr)	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	const unsigned long mask = L_PTE_EXEC | L_PTE_WRITE | L_PTE_USER;
+	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
+	return pte;
+}
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+/* Encode and decode a swap entry.
+ *
+ * We support up to 32GB of swap on 4k machines
+ */
+#define __swp_type(x)		(((x).val >> 2) & 0x7f)
+#define __swp_offset(x)		((x).val >> 9)
+#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 2) | ((offset) << 9) })
+#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
+
+/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
+/* FIXME: this is not correct */
+#define kern_addr_valid(addr)	(1)
+
+#include <asm-generic/pgtable.h>
+
+/*
+ * We provide our own arch_get_unmapped_area to cope with VIPT caches.
+ */
+#define HAVE_ARCH_UNMAPPED_AREA
+
+/*
+ * remap a physical page `pfn' of size `size' with page protection `prot'
+ * into virtual address `from'
+ */
+#define io_remap_pfn_range(vma,from,pfn,size,prot) \
+		remap_pfn_range(vma, from, pfn, size, prot)
+
+#define pgtable_cache_init() do { } while (0)
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* CONFIG_MMU */
+
+#endif /* _ASMARM_PGTABLE_H */