arm64: MMU definitions
The virtual memory layout is described in
Documentation/arm64/memory.txt. This patch adds the MMU definitions for
the 4KB and 64KB translation table configurations. The SECTION_SIZE is
2MB with 4KB page and 512MB with 64KB page configuration.
PHYS_OFFSET is calculated at run-time and stored in a variable (no
run-time code patching at this stage).
On the current implementation, both user and kernel address spaces are
512G (39-bit) each with a maximum of 256G for the RAM linear mapping.
Linux uses 3 levels of translation tables with the 4K page configuration
and 2 levels with the 64K configuration. Extending the memory space
beyond 39-bit with the 4K pages or 42-bit with 64K pages requires an
additional level of translation tables.
The SPARSEMEM configuration is global to all AArch64 platforms and
allows for 1GB sections with SPARSEMEM_VMEMMAP enabled by default.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
new file mode 100644
index 0000000..8960239
--- /dev/null
+++ b/arch/arm64/include/asm/pgtable.h
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PGTABLE_H
+#define __ASM_PGTABLE_H
+
+#include <asm/proc-fns.h>
+
+#include <asm/memory.h>
+#include <asm/pgtable-hwdef.h>
+
+/*
+ * Software defined PTE bits definition.
+ */
+#define PTE_VALID (_AT(pteval_t, 1) << 0) /* pte_present() check */
+#define PTE_FILE (_AT(pteval_t, 1) << 2) /* only when !pte_present() */
+#define PTE_DIRTY (_AT(pteval_t, 1) << 55)
+#define PTE_SPECIAL (_AT(pteval_t, 1) << 56)
+
+/*
+ * VMALLOC and SPARSEMEM_VMEMMAP ranges.
+ */
+#define VMALLOC_START UL(0xffffff8000000000)
+#define VMALLOC_END (PAGE_OFFSET - UL(0x400000000) - SZ_64K)
+
+#define vmemmap ((struct page *)(VMALLOC_END + SZ_64K))
+
+#define FIRST_USER_ADDRESS 0
+
+#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))
+#ifndef CONFIG_ARM64_64K_PAGES
+#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
+#endif
+#define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
+
+/*
+ * The pgprot_* and protection_map entries will be fixed up at 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 _PAGE_DEFAULT PTE_TYPE_PAGE | PTE_AF
+
+extern pgprot_t pgprot_default;
+
+#define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
+
+#define PAGE_NONE _MOD_PROT(pgprot_default, PTE_NG | PTE_XN | PTE_RDONLY)
+#define PAGE_SHARED _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_XN)
+#define PAGE_SHARED_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG)
+#define PAGE_COPY _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_XN | PTE_RDONLY)
+#define PAGE_COPY_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_RDONLY)
+#define PAGE_READONLY _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_XN | PTE_RDONLY)
+#define PAGE_READONLY_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_RDONLY)
+#define PAGE_KERNEL _MOD_PROT(pgprot_default, PTE_XN | PTE_DIRTY)
+#define PAGE_KERNEL_EXEC _MOD_PROT(pgprot_default, PTE_DIRTY)
+
+#define __PAGE_NONE __pgprot(_PAGE_DEFAULT | PTE_NG | PTE_XN | PTE_RDONLY)
+#define __PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_XN)
+#define __PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG)
+#define __PAGE_COPY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_XN | PTE_RDONLY)
+#define __PAGE_COPY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_RDONLY)
+#define __PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_XN | PTE_RDONLY)
+#define __PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_RDONLY)
+
+#endif /* __ASSEMBLY__ */
+
+#define __P000 __PAGE_NONE
+#define __P001 __PAGE_READONLY
+#define __P010 __PAGE_COPY
+#define __P011 __PAGE_COPY
+#define __P100 __PAGE_READONLY_EXEC
+#define __P101 __PAGE_READONLY_EXEC
+#define __P110 __PAGE_COPY_EXEC
+#define __P111 __PAGE_COPY_EXEC
+
+#define __S000 __PAGE_NONE
+#define __S001 __PAGE_READONLY
+#define __S010 __PAGE_SHARED
+#define __S011 __PAGE_SHARED
+#define __S100 __PAGE_READONLY_EXEC
+#define __S101 __PAGE_READONLY_EXEC
+#define __S110 __PAGE_SHARED_EXEC
+#define __S111 __PAGE_SHARED_EXEC
+
+#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) & PHYS_MASK) >> PAGE_SHIFT)
+
+#define pfn_pte(pfn,prot) (__pte(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+
+#define pte_none(pte) (!pte_val(pte))
+#define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(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) pte_offset_kernel((dir), (addr))
+#define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
+#define pte_unmap(pte) do { } while (0)
+#define pte_unmap_nested(pte) do { } while (0)
+
+/*
+ * The following only work if pte_present(). Undefined behaviour otherwise.
+ */
+#define pte_present(pte) (pte_val(pte) & PTE_VALID)
+#define pte_dirty(pte) (pte_val(pte) & PTE_DIRTY)
+#define pte_young(pte) (pte_val(pte) & PTE_AF)
+#define pte_special(pte) (pte_val(pte) & PTE_SPECIAL)
+#define pte_write(pte) (!(pte_val(pte) & PTE_RDONLY))
+#define pte_exec(pte) (!(pte_val(pte) & PTE_XN))
+
+#define pte_present_exec_user(pte) \
+ ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_XN)) == \
+ (PTE_VALID | PTE_USER))
+
+#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, |= PTE_RDONLY);
+PTE_BIT_FUNC(mkwrite, &= ~PTE_RDONLY);
+PTE_BIT_FUNC(mkclean, &= ~PTE_DIRTY);
+PTE_BIT_FUNC(mkdirty, |= PTE_DIRTY);
+PTE_BIT_FUNC(mkold, &= ~PTE_AF);
+PTE_BIT_FUNC(mkyoung, |= PTE_AF);
+PTE_BIT_FUNC(mkspecial, |= PTE_SPECIAL);
+
+static inline void set_pte(pte_t *ptep, pte_t pte)
+{
+ *ptep = pte;
+}
+
+extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
+
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ if (pte_present_exec_user(pte))
+ __sync_icache_dcache(pte, addr);
+ set_pte(ptep, pte);
+}
+
+/*
+ * Huge pte definitions.
+ */
+#define pte_huge(pte) ((pte_val(pte) & PTE_TYPE_MASK) == PTE_TYPE_HUGEPAGE)
+#define pte_mkhuge(pte) (__pte((pte_val(pte) & ~PTE_TYPE_MASK) | PTE_TYPE_HUGEPAGE))
+
+#define __pgprot_modify(prot,mask,bits) \
+ __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
+
+#define __HAVE_ARCH_PTE_SPECIAL
+
+/*
+ * Mark the prot value as uncacheable and unbufferable.
+ */
+#define pgprot_noncached(prot) \
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE))
+#define pgprot_writecombine(prot) \
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_GRE))
+#define pgprot_dmacoherent(prot) \
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
+#define __HAVE_PHYS_MEM_ACCESS_PROT
+struct file;
+extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t vma_prot);
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_present(pmd) (pmd_val(pmd))
+
+#define pmd_bad(pmd) (!(pmd_val(pmd) & 2))
+
+static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+ *pmdp = pmd;
+ dsb();
+}
+
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ set_pmd(pmdp, __pmd(0));
+}
+
+static inline pte_t *pmd_page_vaddr(pmd_t pmd)
+{
+ return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
+}
+
+#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
+
+/*
+ * 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)
+
+#ifndef CONFIG_ARM64_64K_PAGES
+
+#define pud_none(pud) (!pud_val(pud))
+#define pud_bad(pud) (!(pud_val(pud) & 2))
+#define pud_present(pud) (pud_val(pud))
+
+static inline void set_pud(pud_t *pudp, pud_t pud)
+{
+ *pudp = pud;
+ dsb();
+}
+
+static inline void pud_clear(pud_t *pudp)
+{
+ set_pud(pudp, __pud(0));
+}
+
+static inline pmd_t *pud_page_vaddr(pud_t pud)
+{
+ return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
+}
+
+#endif /* CONFIG_ARM64_64K_PAGES */
+
+/* to find an entry in a page-table-directory */
+#define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
+
+#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.. */
+#ifndef CONFIG_ARM64_64K_PAGES
+#define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
+static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
+{
+ return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
+}
+#endif
+
+/* 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 pteval_t mask = PTE_USER | PTE_XN | PTE_RDONLY;
+ pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
+ return pte;
+}
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
+
+#define SWAPPER_DIR_SIZE (3 * PAGE_SIZE)
+#define IDMAP_DIR_SIZE (2 * PAGE_SIZE)
+
+/*
+ * Encode and decode a swap entry:
+ * bits 0-1: present (must be zero)
+ * bit 2: PTE_FILE
+ * bits 3-8: swap type
+ * bits 9-63: swap offset
+ */
+#define __SWP_TYPE_SHIFT 3
+#define __SWP_TYPE_BITS 6
+#define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
+#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
+
+#define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
+#define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
+#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
+
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
+
+/*
+ * Ensure that there are not more swap files than can be encoded in the kernel
+ * the PTEs.
+ */
+#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
+
+/*
+ * Encode and decode a file entry:
+ * bits 0-1: present (must be zero)
+ * bit 2: PTE_FILE
+ * bits 3-63: file offset / PAGE_SIZE
+ */
+#define pte_file(pte) (pte_val(pte) & PTE_FILE)
+#define pte_to_pgoff(x) (pte_val(x) >> 3)
+#define pgoff_to_pte(x) __pte(((x) << 3) | PTE_FILE)
+
+#define PTE_FILE_MAX_BITS 61
+
+extern int kern_addr_valid(unsigned long addr);
+
+#include <asm-generic/pgtable.h>
+
+/*
+ * 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 /* __ASM_PGTABLE_H */