1 files changed, 339 insertions, 0 deletions

diff --git a/arch/tile/include/asm/page.h b/arch/tile/include/asm/page.h
new file mode 100644
index 00000000000..f894a9016da
--- /dev/null
+++ b/arch/tile/include/asm/page.h
@@ -0,0 +1,339 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_PAGE_H
+#define _ASM_TILE_PAGE_H
+
+#include <linux/const.h>
+
+/* PAGE_SHIFT and HPAGE_SHIFT determine the page sizes. */
+#define PAGE_SHIFT      16
+#define HPAGE_SHIFT     24
+
+#define PAGE_SIZE       (_AC(1, UL) << PAGE_SHIFT)
+#define HPAGE_SIZE      (_AC(1, UL) << HPAGE_SHIFT)
+
+#define PAGE_MASK       (~(PAGE_SIZE - 1))
+#define HPAGE_MASK      (~(HPAGE_SIZE - 1))
+
+#ifdef __KERNEL__
+
+#include <hv/hypervisor.h>
+#include <arch/chip.h>
+
+/*
+ * The {,H}PAGE_SHIFT values must match the HV_LOG2_PAGE_SIZE_xxx
+ * definitions in <hv/hypervisor.h>.  We validate this at build time
+ * here, and again at runtime during early boot.  We provide a
+ * separate definition since userspace doesn't have <hv/hypervisor.h>.
+ *
+ * Be careful to distinguish PAGE_SHIFT from HV_PTE_INDEX_PFN, since
+ * they are the same on i386 but not TILE.
+ */
+#if HV_LOG2_PAGE_SIZE_SMALL != PAGE_SHIFT
+# error Small page size mismatch in Linux
+#endif
+#if HV_LOG2_PAGE_SIZE_LARGE != HPAGE_SHIFT
+# error Huge page size mismatch in Linux
+#endif
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <linux/string.h>
+
+struct page;
+
+static inline void clear_page(void *page)
+{
+        memset(page, 0, PAGE_SIZE);
+}
+
+static inline void copy_page(void *to, void *from)
+{
+        memcpy(to, from, PAGE_SIZE);
+}
+
+static inline void clear_user_page(void *page, unsigned long vaddr,
+                                struct page *pg)
+{
+        clear_page(page);
+}
+
+static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
+                                struct page *topage)
+{
+        copy_page(to, from);
+}
+
+/*
+ * Hypervisor page tables are made of the same basic structure.
+ */
+
+typedef __u64 pteval_t;
+typedef __u64 pmdval_t;
+typedef __u64 pudval_t;
+typedef __u64 pgdval_t;
+typedef __u64 pgprotval_t;
+
+typedef HV_PTE pte_t;
+typedef HV_PTE pgd_t;
+typedef HV_PTE pgprot_t;
+
+/*
+ * User L2 page tables are managed as one L2 page table per page,
+ * because we use the page allocator for them.  This keeps the allocation
+ * simple and makes it potentially useful to implement HIGHPTE at some point.
+ * However, it's also inefficient, since L2 page tables are much smaller
+ * than pages (currently 2KB vs 64KB).  So we should revisit this.
+ */
+typedef struct page *pgtable_t;
+
+/* Must be a macro since it is used to create constants. */
+#define __pgprot(val) hv_pte(val)
+
+static inline u64 pgprot_val(pgprot_t pgprot)
+{
+        return hv_pte_val(pgprot);
+}
+
+static inline u64 pte_val(pte_t pte)
+{
+        return hv_pte_val(pte);
+}
+
+static inline u64 pgd_val(pgd_t pgd)
+{
+        return hv_pte_val(pgd);
+}
+
+#ifdef __tilegx__
+
+typedef HV_PTE pmd_t;
+
+static inline u64 pmd_val(pmd_t pmd)
+{
+        return hv_pte_val(pmd);
+}
+
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
+#define HUGETLB_PAGE_ORDER      (HPAGE_SHIFT - PAGE_SHIFT)
+
+#define HUGE_MAX_HSTATE         2
+
+#ifdef CONFIG_HUGETLB_PAGE
+#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#endif
+
+/* Each memory controller has PAs distinct in their high bits. */
+#define NR_PA_HIGHBIT_SHIFT (CHIP_PA_WIDTH() - CHIP_LOG_NUM_MSHIMS())
+#define NR_PA_HIGHBIT_VALUES (1 << CHIP_LOG_NUM_MSHIMS())
+#define __pa_to_highbits(pa) ((phys_addr_t)(pa) >> NR_PA_HIGHBIT_SHIFT)
+#define __pfn_to_highbits(pfn) ((pfn) >> (NR_PA_HIGHBIT_SHIFT - PAGE_SHIFT))
+
+#ifdef __tilegx__
+
+/*
+ * We reserve the lower half of memory for user-space programs, and the
+ * upper half for system code.  We re-map all of physical memory in the
+ * upper half, which takes a quarter of our VA space.  Then we have
+ * the vmalloc regions.  The supervisor code lives at 0xfffffff700000000,
+ * with the hypervisor above that.
+ *
+ * Loadable kernel modules are placed immediately after the static
+ * supervisor code, with each being allocated a 256MB region of
+ * address space, so we don't have to worry about the range of "jal"
+ * and other branch instructions.
+ *
+ * For now we keep life simple and just allocate one pmd (4GB) for vmalloc.
+ * Similarly, for now we don't play any struct page mapping games.
+ */
+
+#if CHIP_PA_WIDTH() + 2 > CHIP_VA_WIDTH()
+# error Too much PA to map with the VA available!
+#endif
+#define HALF_VA_SPACE           (_AC(1, UL) << (CHIP_VA_WIDTH() - 1))
+
+#define MEM_LOW_END             (HALF_VA_SPACE - 1)         /* low half */
+#define MEM_HIGH_START          (-HALF_VA_SPACE)            /* high half */
+#define PAGE_OFFSET             MEM_HIGH_START
+#define _VMALLOC_START          _AC(0xfffffff500000000, UL) /* 4 GB */
+#define HUGE_VMAP_BASE          _AC(0xfffffff600000000, UL) /* 4 GB */
+#define MEM_SV_START            _AC(0xfffffff700000000, UL) /* 256 MB */
+#define MEM_SV_INTRPT           MEM_SV_START
+#define MEM_MODULE_START        _AC(0xfffffff710000000, UL) /* 256 MB */
+#define MEM_MODULE_END          (MEM_MODULE_START + (256*1024*1024))
+#define MEM_HV_START            _AC(0xfffffff800000000, UL) /* 32 GB */
+
+/* Highest DTLB address we will use */
+#define KERNEL_HIGH_VADDR       MEM_SV_START
+
+/* Since we don't currently provide any fixmaps, we use an impossible VA. */
+#define FIXADDR_TOP             MEM_HV_START
+
+#else /* !__tilegx__ */
+
+/*
+ * A PAGE_OFFSET of 0xC0000000 means that the kernel has
+ * a virtual address space of one gigabyte, which limits the
+ * amount of physical memory you can use to about 768MB.
+ * If you want more physical memory than this then see the CONFIG_HIGHMEM
+ * option in the kernel configuration.
+ *
+ * The top two 16MB chunks in the table below (VIRT and HV) are
+ * unavailable to Linux.  Since the kernel interrupt vectors must live
+ * at 0xfd000000, we map all of the bottom of RAM at this address with
+ * a huge page table entry to minimize its ITLB footprint (as well as
+ * at PAGE_OFFSET).  The last architected requirement is that user
+ * interrupt vectors live at 0xfc000000, so we make that range of
+ * memory available to user processes.  The remaining regions are sized
+ * as shown; after the first four addresses, we show "typical" values,
+ * since the actual addresses depend on kernel #defines.
+ *
+ * MEM_VIRT_INTRPT                 0xff000000
+ * MEM_HV_INTRPT                   0xfe000000
+ * MEM_SV_INTRPT (kernel code)     0xfd000000
+ * MEM_USER_INTRPT (user vector)   0xfc000000
+ * FIX_KMAP_xxx                    0xf8000000 (via NR_CPUS * KM_TYPE_NR)
+ * PKMAP_BASE                      0xf7000000 (via LAST_PKMAP)
+ * HUGE_VMAP                       0xf3000000 (via CONFIG_NR_HUGE_VMAPS)
+ * VMALLOC_START                   0xf0000000 (via __VMALLOC_RESERVE)
+ * mapped LOWMEM                   0xc0000000
+ */
+
+#define MEM_USER_INTRPT         _AC(0xfc000000, UL)
+#define MEM_SV_INTRPT           _AC(0xfd000000, UL)
+#define MEM_HV_INTRPT           _AC(0xfe000000, UL)
+#define MEM_VIRT_INTRPT         _AC(0xff000000, UL)
+
+#define INTRPT_SIZE             0x4000
+
+/* Tolerate page size larger than the architecture interrupt region size. */
+#if PAGE_SIZE > INTRPT_SIZE
+#undef INTRPT_SIZE
+#define INTRPT_SIZE PAGE_SIZE
+#endif
+
+#define KERNEL_HIGH_VADDR       MEM_USER_INTRPT
+#define FIXADDR_TOP             (KERNEL_HIGH_VADDR - PAGE_SIZE)
+
+#define PAGE_OFFSET             _AC(CONFIG_PAGE_OFFSET, UL)
+
+/* On 32-bit architectures we mix kernel modules in with other vmaps. */
+#define MEM_MODULE_START        VMALLOC_START
+#define MEM_MODULE_END          VMALLOC_END
+
+#endif /* __tilegx__ */
+
+#ifndef __ASSEMBLY__
+
+#ifdef CONFIG_HIGHMEM
+
+/* Map kernel virtual addresses to page frames, in HPAGE_SIZE chunks. */
+extern unsigned long pbase_map[];
+extern void *vbase_map[];
+
+static inline unsigned long kaddr_to_pfn(const volatile void *_kaddr)
+{
+        unsigned long kaddr = (unsigned long)_kaddr;
+        return pbase_map[kaddr >> HPAGE_SHIFT] +
+                ((kaddr & (HPAGE_SIZE - 1)) >> PAGE_SHIFT);
+}
+
+static inline void *pfn_to_kaddr(unsigned long pfn)
+{
+        return vbase_map[__pfn_to_highbits(pfn)] + (pfn << PAGE_SHIFT);
+}
+
+static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
+{
+        unsigned long pfn = kaddr_to_pfn(kaddr);
+        return ((phys_addr_t)pfn << PAGE_SHIFT) +
+                ((unsigned long)kaddr & (PAGE_SIZE-1));
+}
+
+static inline void *phys_to_virt(phys_addr_t paddr)
+{
+        return pfn_to_kaddr(paddr >> PAGE_SHIFT) + (paddr & (PAGE_SIZE-1));
+}
+
+/* With HIGHMEM, we pack PAGE_OFFSET through high_memory with all valid VAs. */
+static inline int virt_addr_valid(const volatile void *kaddr)
+{
+        extern void *high_memory;  /* copied from <linux/mm.h> */
+        return ((unsigned long)kaddr >= PAGE_OFFSET && kaddr < high_memory);
+}
+
+#else /* !CONFIG_HIGHMEM */
+
+static inline unsigned long kaddr_to_pfn(const volatile void *kaddr)
+{
+        return ((unsigned long)kaddr - PAGE_OFFSET) >> PAGE_SHIFT;
+}
+
+static inline void *pfn_to_kaddr(unsigned long pfn)
+{
+        return (void *)((pfn << PAGE_SHIFT) + PAGE_OFFSET);
+}
+
+static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
+{
+        return (phys_addr_t)((unsigned long)kaddr - PAGE_OFFSET);
+}
+
+static inline void *phys_to_virt(phys_addr_t paddr)
+{
+        return (void *)((unsigned long)paddr + PAGE_OFFSET);
+}
+
+/* Check that the given address is within some mapped range of PAs. */
+#define virt_addr_valid(kaddr) pfn_valid(kaddr_to_pfn(kaddr))
+
+#endif /* !CONFIG_HIGHMEM */
+
+/* All callers are not consistent in how they call these functions. */
+#define __pa(kaddr) virt_to_phys((void *)(unsigned long)(kaddr))
+#define __va(paddr) phys_to_virt((phys_addr_t)(paddr))
+
+extern int devmem_is_allowed(unsigned long pagenr);
+
+#ifdef CONFIG_FLATMEM
+static inline int pfn_valid(unsigned long pfn)
+{
+        return pfn < max_mapnr;
+}
+#endif
+
+/* Provide as macros since these require some other headers included. */
+#define page_to_pa(page) ((phys_addr_t)(page_to_pfn(page)) << PAGE_SHIFT)
+#define virt_to_page(kaddr) pfn_to_page(kaddr_to_pfn(kaddr))
+#define page_to_virt(page) pfn_to_kaddr(page_to_pfn(page))
+
+struct mm_struct;
+extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
+
+#endif /* !__ASSEMBLY__ */
+
+#define VM_DATA_DEFAULT_FLAGS \
+        (VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#include <asm-generic/memory_model.h>
+#include <asm-generic/getorder.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_TILE_PAGE_H */