ARM: 7075/1: LPAE: Factor out 2-level page table definitions into separate files

This patch moves page table definitions from asm/page.h, asm/pgtable.h
and asm/ptgable-hwdef.h into corresponding *-2level* files.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 2 insertions, 133 deletions

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 5750704e027..d6436dacb17 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -24,6 +24,8 @@
 #include <mach/vmalloc.h>
 #include <asm/pgtable-hwdef.h>
 
+#include <asm/pgtable-2level.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
@@ -41,79 +43,6 @@
 #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, preceded 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
- * +- - - - +       | Linux pt 0 |
- * |        |       +------------+ +1024
- * +--------+ +0    | Linux pt 1 |
- * |        |-----> +------------+ +2048
- * +- - - - + +4    |  h/w pt 0  |
- * |        |-----> +------------+ +3072
- * +--------+ +8    |  h/w 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
-
-#define PTE_HWTABLE_PTRS	(PTRS_PER_PTE)
-#define PTE_HWTABLE_OFF		(PTE_HWTABLE_PTRS * sizeof(pte_t))
-#define PTE_HWTABLE_SIZE	(PTRS_PER_PTE * sizeof(u32))
-
-/*
- * 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__
@@ -124,12 +53,6 @@ extern void __pgd_error(const char *file, int line, pgd_t);
 #define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte)
 #define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd)
 #define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, 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
@@ -138,60 +61,6 @@ extern void __pgd_error(const char *file, int line, pgd_t);
  */
 #define FIRST_USER_ADDRESS	PAGE_SIZE
 
-#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-
-/*
- * 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		(_AT(pteval_t, 1) << 0)
-#define L_PTE_YOUNG		(_AT(pteval_t, 1) << 1)
-#define L_PTE_FILE		(_AT(pteval_t, 1) << 2)	/* only when !PRESENT */
-#define L_PTE_DIRTY		(_AT(pteval_t, 1) << 6)
-#define L_PTE_RDONLY		(_AT(pteval_t, 1) << 7)
-#define L_PTE_USER		(_AT(pteval_t, 1) << 8)
-#define L_PTE_XN		(_AT(pteval_t, 1) << 9)
-#define L_PTE_SHARED		(_AT(pteval_t, 1) << 10)	/* shared(v6), coherent(xsc3) */
-
-/*
- * These are the memory types, defined to be compatible with
- * pre-ARMv6 CPUs cacheable and bufferable bits:   XXCB
- */
-#define L_PTE_MT_UNCACHED	(_AT(pteval_t, 0x00) << 2)	/* 0000 */
-#define L_PTE_MT_BUFFERABLE	(_AT(pteval_t, 0x01) << 2)	/* 0001 */
-#define L_PTE_MT_WRITETHROUGH	(_AT(pteval_t, 0x02) << 2)	/* 0010 */
-#define L_PTE_MT_WRITEBACK	(_AT(pteval_t, 0x03) << 2)	/* 0011 */
-#define L_PTE_MT_MINICACHE	(_AT(pteval_t, 0x06) << 2)	/* 0110 (sa1100, xscale) */
-#define L_PTE_MT_WRITEALLOC	(_AT(pteval_t, 0x07) << 2)	/* 0111 */
-#define L_PTE_MT_DEV_SHARED	(_AT(pteval_t, 0x04) << 2)	/* 0100 */
-#define L_PTE_MT_DEV_NONSHARED	(_AT(pteval_t, 0x0c) << 2)	/* 1100 */
-#define L_PTE_MT_DEV_WC		(_AT(pteval_t, 0x09) << 2)	/* 1001 */
-#define L_PTE_MT_DEV_CACHED	(_AT(pteval_t, 0x0b) << 2)	/* 1011 */
-#define L_PTE_MT_MASK		(_AT(pteval_t, 0x0f) << 2)
-
-#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,