[PATCH 11/30] microblaze_mmu_v1: Page table - ioremap - pgtable.c/h, section update

monstr
2009-04-27T09:58:28Z

From: Michal Simek <monstr@monstr.eu>

Signed-off-by: Michal Simek <monstr@monstr.eu>
---
arch/microblaze/include/asm/pgtable.h | 534 ++++++++++++++++++++++++++++++++
arch/microblaze/include/asm/sections.h | 3 +
arch/microblaze/mm/pgtable.c | 286 +++++++++++++++++
3 files changed, 823 insertions(+), 0 deletions(-)
create mode 100644 arch/microblaze/mm/pgtable.c

diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
index 4df31e4..d1e434d 100644
--- a/arch/microblaze/include/asm/pgtable.h
+++ b/arch/microblaze/include/asm/pgtable.h
@@ -1,4 +1,6 @@
/*
+ * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
@@ -14,6 +16,8 @@
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)

+#ifndef CONFIG_MMU
+
#define pgd_present(pgd) (1) /* pages are always present on non MMU */
#define pgd_none(pgd) (0)
#define pgd_bad(pgd) (0)
@@ -45,6 +49,536 @@ static inline int pte_file(pte_t pte) { return 0; }

#define arch_enter_lazy_cpu_mode() do {} while (0)

+#else /* CONFIG_MMU */
+
+#include <asm-generic/4level-fixup.h>
+
+#ifdef __KERNEL__
+#ifndef __ASSEMBLY__
+
+#include <linux/sched.h>
+#include <linux/threads.h>
+#include <asm/processor.h> /* For TASK_SIZE */
+#include <asm/mmu.h>
+#include <asm/page.h>
+
+#define FIRST_USER_ADDRESS 0
+
+extern unsigned long va_to_phys(unsigned long address);
+extern pte_t *va_to_pte(unsigned long address);
+extern unsigned long ioremap_bot, ioremap_base;
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+
+static inline int pte_special(pte_t pte) { return 0; }
+
+static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
+
+/* Start and end of the vmalloc area. */
+extern unsigned int memory_size;
+#define VMALLOC_START (CONFIG_KERNEL_START + memory_size)
+#define VMALLOC_END ioremap_bot
+#define VMALLOC_VMADDR(x) ((unsigned long)(x))
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * The MicroBlaze MMU is identical to the PPC-40x MMU, and uses a hash
+ * table containing PTEs, together with a set of 16 segment registers, to
+ * define the virtual to physical address mapping.
+ *
+ * We use the hash table as an extended TLB, i.e. a cache of currently
+ * active mappings. We maintain a two-level page table tree, much
+ * like that used by the i386, for the sake of the Linux memory
+ * management code. Low-level assembler code in hashtable.S
+ * (procedure hash_page) is responsible for extracting ptes from the
+ * tree and putting them into the hash table when necessary, and
+ * updating the accessed and modified bits in the page table tree.
+ */
+
+/*
+ * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The
+ * instruction and data sides share a unified, 64-entry, semi-associative
+ * TLB which is maintained totally under software control. In addition, the
+ * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative
+ * TLB which serves as a first level to the shared TLB. These two TLBs are
+ * known as the UTLB and ITLB, respectively (see "mmu.h" for definitions).
+ */
+
+/*
+ * The normal case is that PTEs are 32-bits and we have a 1-page
+ * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
+ *
+ */
+
+/* PMD_SHIFT determines the size of the area mapped by the PTE pages */
+#define PMD_SHIFT (PAGE_SHIFT + PTE_SHIFT)
+#define PMD_SIZE (1UL << PMD_SHIFT)
+#define PMD_MASK (~(PMD_SIZE-1))
+
+/* PGDIR_SHIFT determines what a top-level page table entry can map */
+#define PGDIR_SHIFT PMD_SHIFT
+#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+/*
+ * entries per page directory level: our page-table tree is two-level, so
+ * we don't really have any PMD directory.
+ */
+#define PTRS_PER_PTE (1 << PTE_SHIFT)
+#define PTRS_PER_PMD 1
+#define PTRS_PER_PGD (1 << (32 - PGDIR_SHIFT))
+
+#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
+#define FIRST_USER_PGD_NR 0
+
+#define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
+#define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS)
+
+#define pte_ERROR(e) \
+ printk(KERN_ERR "%s:%d: bad pte "PTE_FMT".\n", \
+ __FILE__, __LINE__, pte_val(e))
+#define pmd_ERROR(e) \
+ printk(KERN_ERR "%s:%d: bad pmd %08lx.\n", \
+ __FILE__, __LINE__, pmd_val(e))
+#define pgd_ERROR(e) \
+ printk(KERN_ERR "%s:%d: bad pgd %08lx.\n", \
+ __FILE__, __LINE__, pgd_val(e))
+
+/*
+ * Bits in a linux-style PTE. These match the bits in the
+ * (hardware-defined) PTE as closely as possible.
+ */
+
+/* There are several potential gotchas here. The hardware TLBLO
+ * field looks like this:
+ *
+ * 0 1 2 3 4 ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+ * RPN..................... 0 0 EX WR ZSEL....... W I M G
+ *
+ * Where possible we make the Linux PTE bits match up with this
+ *
+ * - bits 20 and 21 must be cleared, because we use 4k pages (4xx can
+ * support down to 1k pages), this is done in the TLBMiss exception
+ * handler.
+ * - We use only zones 0 (for kernel pages) and 1 (for user pages)
+ * of the 16 available. Bit 24-26 of the TLB are cleared in the TLB
+ * miss handler. Bit 27 is PAGE_USER, thus selecting the correct
+ * zone.
+ * - PRESENT *must* be in the bottom two bits because swap cache
+ * entries use the top 30 bits. Because 4xx doesn't support SMP
+ * anyway, M is irrelevant so we borrow it for PAGE_PRESENT. Bit 30
+ * is cleared in the TLB miss handler before the TLB entry is loaded.
+ * - All other bits of the PTE are loaded into TLBLO without
+ * * modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for
+ * software PTE bits. We actually use use bits 21, 24, 25, and
+ * 30 respectively for the software bits: ACCESSED, DIRTY, RW, and
+ * PRESENT.
+ */
+
+/* Definitions for MicroBlaze. */
+#define _PAGE_GUARDED 0x001 /* G: page is guarded from prefetch */
+#define _PAGE_PRESENT 0x002 /* software: PTE contains a translation */
+#define _PAGE_NO_CACHE 0x004 /* I: caching is inhibited */
+#define _PAGE_WRITETHRU 0x008 /* W: caching is write-through */
+#define _PAGE_USER 0x010 /* matches one of the zone permission bits */
+#define _PAGE_RW 0x040 /* software: Writes permitted */
+#define _PAGE_DIRTY 0x080 /* software: dirty page */
+#define _PAGE_HWWRITE 0x100 /* hardware: Dirty & RW, set in exception */
+#define _PAGE_HWEXEC 0x200 /* hardware: EX permission */
+#define _PAGE_ACCESSED 0x400 /* software: R: page referenced */
+#define _PMD_PRESENT PAGE_MASK
+
+/*
+ * Some bits are unused...
+ */
+#ifndef _PAGE_HASHPTE
+#define _PAGE_HASHPTE 0
+#endif
+#ifndef _PTE_NONE_MASK
+#define _PTE_NONE_MASK 0
+#endif
+#ifndef _PAGE_SHARED
+#define _PAGE_SHARED 0
+#endif
+#ifndef _PAGE_HWWRITE
+#define _PAGE_HWWRITE 0
+#endif
+#ifndef _PAGE_HWEXEC
+#define _PAGE_HWEXEC 0
+#endif
+#ifndef _PAGE_EXEC
+#define _PAGE_EXEC 0
+#endif
+
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
+
+/*
+ * Note: the _PAGE_COHERENT bit automatically gets set in the hardware
+ * PTE if CONFIG_SMP is defined (hash_page does this); there is no need
+ * to have it in the Linux PTE, and in fact the bit could be reused for
+ * another purpose. -- paulus.
+ */
+#define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED)
+#define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE)
+
+#define _PAGE_KERNEL \
+ (_PAGE_BASE | _PAGE_WRENABLE | _PAGE_SHARED | _PAGE_HWEXEC)
+
+#define _PAGE_IO (_PAGE_KERNEL | _PAGE_NO_CACHE | _PAGE_GUARDED)
+
+#define PAGE_NONE __pgprot(_PAGE_BASE)
+#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
+#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
+#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
+#define PAGE_SHARED_X \
+ __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
+#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER)
+#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
+
+#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
+#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_SHARED)
+#define PAGE_KERNEL_CI __pgprot(_PAGE_IO)
+
+/*
+ * We consider execute permission the same as read.
+ * Also, write permissions imply read permissions.
+ */
+#define __P000 PAGE_NONE
+#define __P001 PAGE_READONLY_X
+#define __P010 PAGE_COPY
+#define __P011 PAGE_COPY_X
+#define __P100 PAGE_READONLY
+#define __P101 PAGE_READONLY_X
+#define __P110 PAGE_COPY
+#define __P111 PAGE_COPY_X
+
+#define __S000 PAGE_NONE
+#define __S001 PAGE_READONLY_X
+#define __S010 PAGE_SHARED
+#define __S011 PAGE_SHARED_X
+#define __S100 PAGE_READONLY
+#define __S101 PAGE_READONLY_X
+#define __S110 PAGE_SHARED
+#define __S111 PAGE_SHARED_X
+
+#ifndef __ASSEMBLY__
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+extern unsigned long empty_zero_page[1024];
+#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+
+#endif /* __ASSEMBLY__ */
+
+#define pte_none(pte) ((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
+#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
+#define pte_clear(mm, addr, ptep) \
+ do { set_pte_at((mm), (addr), (ptep), __pte(0)); } while (0)
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) ((pmd_val(pmd) & _PMD_PRESENT) == 0)
+#define pmd_present(pmd) ((pmd_val(pmd) & _PMD_PRESENT) != 0)
+#define pmd_clear(pmdp) do { pmd_val(*(pmdp)) = 0; } while (0)
+
+#define pte_page(x) (mem_map + (unsigned long) \
+ ((pte_val(x) - memory_start) >> PAGE_SHIFT))
+#define PFN_SHIFT_OFFSET (PAGE_SHIFT)
+
+#define pte_pfn(x) (pte_val(x) >> PFN_SHIFT_OFFSET)
+
+#define pfn_pte(pfn, prot) \
+ __pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) | pgprot_val(prot))
+
+#ifndef __ASSEMBLY__
+/*
+ * 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)
+ */
+static inline int pgd_none(pgd_t pgd) { return 0; }
+static inline int pgd_bad(pgd_t pgd) { return 0; }
+static inline int pgd_present(pgd_t pgd) { return 1; }
+#define pgd_clear(xp) do { } while (0)
+#define pgd_page(pgd) \
+ ((unsigned long) __va(pgd_val(pgd) & PAGE_MASK))
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER; }
+static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; }
+static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; }
+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; }
+/* FIXME */
+static inline int pte_file(pte_t pte) { return 0; }
+
+static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; }
+static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; }
+
+static inline pte_t pte_rdprotect(pte_t pte) \
+ { pte_val(pte) &= ~_PAGE_USER; return pte; }
+static inline pte_t pte_wrprotect(pte_t pte) \
+ { pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; }
+static inline pte_t pte_exprotect(pte_t pte) \
+ { pte_val(pte) &= ~_PAGE_EXEC; return pte; }
+static inline pte_t pte_mkclean(pte_t pte) \
+ { pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; }
+static inline pte_t pte_mkold(pte_t pte) \
+ { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
+
+static inline pte_t pte_mkread(pte_t pte) \
+ { pte_val(pte) |= _PAGE_USER; return pte; }
+static inline pte_t pte_mkexec(pte_t pte) \
+ { pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; }
+static inline pte_t pte_mkwrite(pte_t pte) \
+ { pte_val(pte) |= _PAGE_RW; return pte; }
+static inline pte_t pte_mkdirty(pte_t pte) \
+ { pte_val(pte) |= _PAGE_DIRTY; return pte; }
+static inline pte_t pte_mkyoung(pte_t pte) \
+ { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+
+static inline pte_t mk_pte_phys(phys_addr_t physpage, pgprot_t pgprot)
+{
+ pte_t pte;
+ pte_val(pte) = physpage | pgprot_val(pgprot);
+ return pte;
+}
+
+#define mk_pte(page, pgprot) \
+({ \
+ pte_t pte; \
+ pte_val(pte) = (((page - mem_map) << PAGE_SHIFT) + memory_start) | \
+ pgprot_val(pgprot); \
+ pte; \
+})
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
+ return pte;
+}
+
+/*
+ * Atomic PTE updates.
+ *
+ * pte_update clears and sets bit atomically, and returns
+ * the old pte value.
+ * The ((unsigned long)(p+1) - 4) hack is to get to the least-significant
+ * 32 bits of the PTE regardless of whether PTEs are 32 or 64 bits.
+ */
+static inline unsigned long pte_update(pte_t *p, unsigned long clr,
+ unsigned long set)
+{
+ unsigned long old, tmp, msr;
+
+ __asm__ __volatile__("\
+ msrclr %2, 0x2\n\
+ nop\n\
+ lw %0, %4, r0\n\
+ andn %1, %0, %5\n\
+ or %1, %1, %6\n\
+ sw %1, %4, r0\n\
+ mts rmsr, %2\n\
+ nop"
+ : "=&r" (old), "=&r" (tmp), "=&r" (msr), "=m" (*p)
+ : "r" ((unsigned long)(p+1) - 4), "r" (clr), "r" (set), "m" (*p)
+ : "cc");
+
+ return old;
+}
+
+/*
+ * set_pte stores a linux PTE into the linux page table.
+ */
+static inline void set_pte(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ *ptep = pte;
+}
+
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ *ptep = pte;
+}
+
+static inline int ptep_test_and_clear_young(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ return (pte_update(ptep, _PAGE_ACCESSED, 0) & _PAGE_ACCESSED) != 0;
+}
+
+static inline int ptep_test_and_clear_dirty(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ return (pte_update(ptep, \
+ (_PAGE_DIRTY | _PAGE_HWWRITE), 0) & _PAGE_DIRTY) != 0;
+}
+
+static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
+}
+
+/*static inline void ptep_set_wrprotect(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
+}*/
+
+static inline void ptep_mkdirty(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ pte_update(ptep, 0, _PAGE_DIRTY);
+}
+
+/*#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)*/
+
+/* Convert pmd entry to page */
+/* our pmd entry is an effective address of pte table*/
+/* returns effective address of the pmd entry*/
+#define pmd_page_kernel(pmd) ((unsigned long) (pmd_val(pmd) & PAGE_MASK))
+
+/* returns struct *page of the pmd entry*/
+#define pmd_page(pmd) (pfn_to_page(__pa(pmd_val(pmd)) >> PAGE_SHIFT))
+
+/* to find an entry in a kernel page-table-directory */
+#define pgd_offset_k(address) pgd_offset(&init_mm, address)
+
+/* to find an entry in a page-table-directory */
+#define pgd_index(address) ((address) >> PGDIR_SHIFT)
+#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
+
+/* Find an entry in the second-level page table.. */
+static inline pmd_t *pmd_offset(pgd_t *dir, unsigned long address)
+{
+ return (pmd_t *) dir;
+}
+
+/* Find an entry in the third-level page table.. */
+#define pte_index(address) \
+ (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+#define pte_offset_kernel(dir, addr) \
+ ((pte_t *) pmd_page_kernel(*(dir)) + pte_index(addr))
+#define pte_offset_map(dir, addr) \
+ ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE0) + pte_index(addr))
+#define pte_offset_map_nested(dir, addr) \
+ ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE1) + pte_index(addr))
+
+#define pte_unmap(pte) kunmap_atomic(pte, KM_PTE0)
+#define pte_unmap_nested(pte) kunmap_atomic(pte, KM_PTE1)
+
+/* Encode and decode a nonlinear file mapping entry */
+#define PTE_FILE_MAX_BITS 29
+#define pte_to_pgoff(pte) (pte_val(pte) >> 3)
+#define pgoff_to_pte(off) ((pte_t) { ((off) << 3) })
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+/*
+ * When flushing the tlb entry for a page, we also need to flush the hash
+ * table entry. flush_hash_page is assembler (for speed) in hashtable.S.
+ */
+extern int flush_hash_page(unsigned context, unsigned long va, pte_t *ptep);
+
+/* Add an HPTE to the hash table */
+extern void add_hash_page(unsigned context, unsigned long va, pte_t *ptep);
+
+/*
+ * Encode and decode a swap entry.
+ * Note that the bits we use in a PTE for representing a swap entry
+ * must not include the _PAGE_PRESENT bit, or the _PAGE_HASHPTE bit
+ * (if used). -- paulus
+ */
+#define __swp_type(entry) ((entry).val & 0x3f)
+#define __swp_offset(entry) ((entry).val >> 6)
+#define __swp_entry(type, offset) \
+ ((swp_entry_t) { (type) | ((offset) << 6) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 2 })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 2 })
+
+
+/* CONFIG_APUS */
+/* For virtual address to physical address conversion */
+extern void cache_clear(__u32 addr, int length);
+extern void cache_push(__u32 addr, int length);
+extern int mm_end_of_chunk(unsigned long addr, int len);
+extern unsigned long iopa(unsigned long addr);
+/* extern unsigned long mm_ptov(unsigned long addr) \
+ __attribute__ ((const)); TBD */
+
+/* Values for nocacheflag and cmode */
+/* These are not used by the APUS kernel_map, but prevents
+ * compilation errors.
+ */
+#define IOMAP_FULL_CACHING 0
+#define IOMAP_NOCACHE_SER 1
+#define IOMAP_NOCACHE_NONSER 2
+#define IOMAP_NO_COPYBACK 3
+
+/*
+ * Map some physical address range into the kernel address space.
+ */
+extern unsigned long kernel_map(unsigned long paddr, unsigned long size,
+ int nocacheflag, unsigned long *memavailp);
+
+/*
+ * Set cache mode of (kernel space) address range.
+ */
+extern void kernel_set_cachemode(unsigned long address, unsigned long size,
+ unsigned int cmode);
+
+/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
+#define kern_addr_valid(addr) (1)
+
+#define io_remap_page_range remap_page_range
+
+/*
+ * No page table caches to initialise
+ */
+#define pgtable_cache_init() do { } while (0)
+
+void do_page_fault(struct pt_regs *regs, unsigned long address,
+ unsigned long error_code);
+
+void __init io_block_mapping(unsigned long virt, phys_addr_t phys,
+ unsigned int size, int flags);
+
+void __init adjust_total_lowmem(void);
+void mapin_ram(void);
+int map_page(unsigned long va, phys_addr_t pa, int flags);
+
+extern int mem_init_done;
+extern unsigned long ioremap_base;
+extern unsigned long ioremap_bot;
+
+asmlinkage void __init MMU_init(void);
+
+void __init *early_get_page(void);
+
+void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle);
+void consistent_free(void *vaddr);
+void consistent_sync(void *vaddr, size_t size, int direction);
+void consistent_sync_page(struct page *page, unsigned long offset,
+ size_t size, int direction);
+#endif /* __ASSEMBLY__ */
+#endif /* __KERNEL__ */
+
+#endif /* CONFIG_MMU */
+
#ifndef __ASSEMBLY__
#include <asm-generic/pgtable.h>

diff --git a/arch/microblaze/include/asm/sections.h b/arch/microblaze/include/asm/sections.h
index 8434a43..4487e15 100644
--- a/arch/microblaze/include/asm/sections.h
+++ b/arch/microblaze/include/asm/sections.h
@@ -1,4 +1,6 @@
/*
+ * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
@@ -14,6 +16,7 @@
# ifndef __ASSEMBLY__
extern char _ssbss[], _esbss[];
extern unsigned long __ivt_start[], __ivt_end[];
+extern char _etext[], _stext[];

# ifdef CONFIG_MTD_UCLINUX
extern char *_ebss;
diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c
new file mode 100644
index 0000000..46c4ca5
--- /dev/null
+++ b/arch/microblaze/mm/pgtable.c
@@ -0,0 +1,286 @@
+/*
+ * This file contains the routines setting up the linux page tables.
+ *
+ * Copyright (C) 2008 Michal Simek
+ * Copyright (C) 2008 PetaLogix
+ *
+ * Copyright (C) 2007 Xilinx, Inc. All rights reserved.
+ *
+ * Derived from arch/ppc/mm/pgtable.c:
+ * -- paulus
+ *
+ * Derived from arch/ppc/mm/init.c:
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <linux/io.h>
+#include <asm/mmu.h>
+#include <asm/sections.h>
+
+#define flush_HPTE(X, va, pg) _tlbie(va)
+
+unsigned long ioremap_base;
+unsigned long ioremap_bot;
+
+/* The maximum lowmem defaults to 768Mb, but this can be configured to
+ * another value.
+ */
+#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE
+
+#ifndef CONFIG_SMP
+struct pgtable_cache_struct quicklists;
+#endif
+
+static void __iomem *__ioremap(phys_addr_t addr, unsigned long size,
+ unsigned long flags)
+{
+ unsigned long v, i;
+ phys_addr_t p;
+ int err;
+
+ /*
+ * Choose an address to map it to.
+ * Once the vmalloc system is running, we use it.
+ * Before then, we use space going down from ioremap_base
+ * (ioremap_bot records where we're up to).
+ */
+ p = addr & PAGE_MASK;
+ size = PAGE_ALIGN(addr + size) - p;
+
+ /*
+ * Don't allow anybody to remap normal RAM that we're using.
+ * mem_init() sets high_memory so only do the check after that.
+ *
+ * However, allow remap of rootfs: TBD
+ */
+ if (mem_init_done &&
+ p >= memory_start && p < virt_to_phys(high_memory) &&
+ !(p >= virt_to_phys((unsigned long)&__bss_stop) &&
+ p < virt_to_phys((unsigned long)__bss_stop))) {
+ printk(KERN_WARNING "__ioremap(): phys addr "PTE_FMT
+ " is RAM lr %p\n", (unsigned long)p,
+ __builtin_return_address(0));
+ return NULL;
+ }
+
+ if (size == 0)
+ return NULL;
+
+ /*
+ * Is it already mapped? If the whole area is mapped then we're
+ * done, otherwise remap it since we want to keep the virt addrs for
+ * each request contiguous.
+ *
+ * We make the assumption here that if the bottom and top
+ * of the range we want are mapped then it's mapped to the
+ * same virt address (and this is contiguous).
+ * -- Cort
+ */
+
+ if (mem_init_done) {
+ struct vm_struct *area;
+ area = get_vm_area(size, VM_IOREMAP);
+ if (area == NULL)
+ return NULL;
+ v = VMALLOC_VMADDR(area->addr);
+ } else {
+ v = (ioremap_bot -= size);
+ }
+
+ if ((flags & _PAGE_PRESENT) == 0)
+ flags |= _PAGE_KERNEL;
+ if (flags & _PAGE_NO_CACHE)
+ flags |= _PAGE_GUARDED;
+
+ err = 0;
+ for (i = 0; i < size && err == 0; i += PAGE_SIZE)
+ err = map_page(v + i, p + i, flags);
+ if (err) {
+ if (mem_init_done)
+ vfree((void *)v);
+ return NULL;
+ }
+
+ return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
+}
+
+void __iomem *ioremap(phys_addr_t addr, unsigned long size)
+{
+ return __ioremap(addr, size, _PAGE_NO_CACHE);
+}
+EXPORT_SYMBOL(ioremap);
+
+void iounmap(void *addr)
+{
+ if (addr > high_memory && (unsigned long) addr < ioremap_bot)
+ vfree((void *) (PAGE_MASK & (unsigned long) addr));
+}
+EXPORT_SYMBOL(iounmap);
+
+
+int map_page(unsigned long va, phys_addr_t pa, int flags)
+{
+ pmd_t *pd;
+ pte_t *pg;
+ int err = -ENOMEM;
+ /* spin_lock(&init_mm.page_table_lock); */
+ /* Use upper 10 bits of VA to index the first level map */
+ pd = pmd_offset(pgd_offset_k(va), va);
+ /* Use middle 10 bits of VA to index the second-level map */
+ pg = pte_alloc_kernel(pd, va); /* from powerpc - pgtable.c */
+ /* pg = pte_alloc_kernel(&init_mm, pd, va); */
+
+ if (pg != NULL) {
+ err = 0;
+ set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
+ __pgprot(flags)));
+ if (mem_init_done)
+ flush_HPTE(0, va, pmd_val(*pd));
+ /* flush_HPTE(0, va, pg); */
+
+ }
+ /* spin_unlock(&init_mm.page_table_lock); */
+ return err;
+}
+
+void __init adjust_total_lowmem(void)
+{
+/* TBD */
+#if 0
+ unsigned long max_low_mem = MAX_LOW_MEM;
+
+ if (total_lowmem > max_low_mem) {
+ total_lowmem = max_low_mem;
+#ifndef CONFIG_HIGHMEM
+ printk(KERN_INFO "Warning, memory limited to %ld Mb, use "
+ "CONFIG_HIGHMEM to reach %ld Mb\n",
+ max_low_mem >> 20, total_memory >> 20);
+ total_memory = total_lowmem;
+#endif /* CONFIG_HIGHMEM */
+ }
+#endif
+}
+
+static void show_tmem(unsigned long tmem)
+{
+ volatile unsigned long a;
+ a = a + tmem;
+}
+
+/*
+ * Map in all of physical memory starting at CONFIG_KERNEL_START.
+ */
+void __init mapin_ram(void)
+{
+ unsigned long v, p, s, f;
+
+ v = CONFIG_KERNEL_START;
+ p = memory_start;
+ show_tmem(memory_size);
+ for (s = 0; s < memory_size; s += PAGE_SIZE) {
+ f = _PAGE_PRESENT | _PAGE_ACCESSED |
+ _PAGE_SHARED | _PAGE_HWEXEC;
+ if ((char *) v < _stext || (char *) v >= _etext)
+ f |= _PAGE_WRENABLE;
+ else
+ /* On the MicroBlaze, no user access
+ forces R/W kernel access */
+ f |= _PAGE_USER;
+ map_page(v, p, f);
+ v += PAGE_SIZE;
+ p += PAGE_SIZE;
+ }
+}
+
+/* is x a power of 2? */
+#define is_power_of_2(x) ((x) != 0 && (((x) & ((x) - 1)) == 0))
+
+/*
+ * Set up a mapping for a block of I/O.
+ * virt, phys, size must all be page-aligned.
+ * This should only be called before ioremap is called.
+ */
+void __init io_block_mapping(unsigned long virt, phys_addr_t phys,
+ unsigned int size, int flags)
+{
+ int i;
+
+ if (virt > CONFIG_KERNEL_START && virt < ioremap_bot)
+ ioremap_bot = ioremap_base = virt;
+
+ /* Put it in the page tables. */
+ for (i = 0; i < size; i += PAGE_SIZE)
+ map_page(virt + i, phys + i, flags);
+}
+
+/* Scan the real Linux page tables and return a PTE pointer for
+ * a virtual address in a context.
+ * Returns true (1) if PTE was found, zero otherwise. The pointer to
+ * the PTE pointer is unmodified if PTE is not found.
+ */
+static int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ int retval = 0;
+
+ pgd = pgd_offset(mm, addr & PAGE_MASK);
+ if (pgd) {
+ pmd = pmd_offset(pgd, addr & PAGE_MASK);
+ if (pmd_present(*pmd)) {
+ pte = pte_offset_kernel(pmd, addr & PAGE_MASK);
+ if (pte) {
+ retval = 1;
+ *ptep = pte;
+ }
+ }
+ }
+ return retval;
+}
+
+/* Find physical address for this virtual address. Normally used by
+ * I/O functions, but anyone can call it.
+ */
+unsigned long iopa(unsigned long addr)
+{
+ unsigned long pa;
+
+ pte_t *pte;
+ struct mm_struct *mm;
+
+ /* Allow mapping of user addresses (within the thread)
+ * for DMA if necessary.
+ */
+ if (addr < TASK_SIZE)
+ mm = current->mm;
+ else
+ mm = &init_mm;
+
+ pa = 0;
+ if (get_pteptr(mm, addr, &pte))
+ pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK);
+
+ return pa;
+}
--
1.5.5.1