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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /arch/powerpc/include/asm/book3s/32
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'arch/powerpc/include/asm/book3s/32')
-rw-r--r--arch/powerpc/include/asm/book3s/32/hash.h46
-rw-r--r--arch/powerpc/include/asm/book3s/32/pgtable.h482
2 files changed, 528 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/hash.h b/arch/powerpc/include/asm/book3s/32/hash.h
new file mode 100644
index 000000000..264b754d6
--- /dev/null
+++ b/arch/powerpc/include/asm/book3s/32/hash.h
@@ -0,0 +1,46 @@
+#ifndef _ASM_POWERPC_BOOK3S_32_HASH_H
+#define _ASM_POWERPC_BOOK3S_32_HASH_H
+#ifdef __KERNEL__
+
+/*
+ * The "classic" 32-bit implementation of the PowerPC MMU 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 hash_low_32.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.
+ */
+
+#define _PAGE_PRESENT 0x001 /* software: pte contains a translation */
+#define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */
+#define _PAGE_USER 0x004 /* usermode access allowed */
+#define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */
+#define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */
+#define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */
+#define _PAGE_WRITETHRU 0x040 /* W: cache write-through */
+#define _PAGE_DIRTY 0x080 /* C: page changed */
+#define _PAGE_ACCESSED 0x100 /* R: page referenced */
+#define _PAGE_RW 0x400 /* software: user write access allowed */
+#define _PAGE_SPECIAL 0x800 /* software: Special page */
+
+#ifdef CONFIG_PTE_64BIT
+/* We never clear the high word of the pte */
+#define _PTE_NONE_MASK (0xffffffff00000000ULL | _PAGE_HASHPTE)
+#else
+#define _PTE_NONE_MASK _PAGE_HASHPTE
+#endif
+
+#define _PMD_PRESENT 0
+#define _PMD_PRESENT_MASK (PAGE_MASK)
+#define _PMD_BAD (~PAGE_MASK)
+
+/* Hash table based platforms need atomic updates of the linux PTE */
+#define PTE_ATOMIC_UPDATES 1
+
+#endif /* __KERNEL__ */
+#endif /* _ASM_POWERPC_BOOK3S_32_HASH_H */
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
new file mode 100644
index 000000000..38b33dcfc
--- /dev/null
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -0,0 +1,482 @@
+#ifndef _ASM_POWERPC_BOOK3S_32_PGTABLE_H
+#define _ASM_POWERPC_BOOK3S_32_PGTABLE_H
+
+#include <asm-generic/pgtable-nopmd.h>
+
+#include <asm/book3s/32/hash.h>
+
+/* And here we include common definitions */
+#include <asm/pte-common.h>
+
+/*
+ * 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
+ *
+ * For any >32-bit physical address platform, we can use the following
+ * two level page table layout where the pgdir is 8KB and the MS 13 bits
+ * are an index to the second level table. The combined pgdir/pmd first
+ * level has 2048 entries and the second level has 512 64-bit PTE entries.
+ * -Matt
+ */
+/* PGDIR_SHIFT determines what a top-level page table entry can map */
+#define PGDIR_SHIFT (PAGE_SHIFT + PTE_SHIFT)
+#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+#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)
+/*
+ * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
+ * value (for now) on others, from where we can start layout kernel
+ * virtual space that goes below PKMAP and FIXMAP
+ */
+#ifdef CONFIG_HIGHMEM
+#define KVIRT_TOP PKMAP_BASE
+#else
+#define KVIRT_TOP (0xfe000000UL) /* for now, could be FIXMAP_BASE ? */
+#endif
+
+/*
+ * ioremap_bot starts at that address. Early ioremaps move down from there,
+ * until mem_init() at which point this becomes the top of the vmalloc
+ * and ioremap space
+ */
+#ifdef CONFIG_NOT_COHERENT_CACHE
+#define IOREMAP_TOP ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
+#else
+#define IOREMAP_TOP KVIRT_TOP
+#endif
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 16MB value just means that there will be a 64MB "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. ;)
+ *
+ * We no longer map larger than phys RAM with the BATs so we don't have
+ * to worry about the VMALLOC_OFFSET causing problems. We do have to worry
+ * about clashes between our early calls to ioremap() that start growing down
+ * from ioremap_base being run into the VM area allocations (growing upwards
+ * from VMALLOC_START). For this reason we have ioremap_bot to check when
+ * we actually run into our mappings setup in the early boot with the VM
+ * system. This really does become a problem for machines with good amounts
+ * of RAM. -- Cort
+ */
+#define VMALLOC_OFFSET (0x1000000) /* 16M */
+#ifdef PPC_PIN_SIZE
+#define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#else
+#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#endif
+#define VMALLOC_END ioremap_bot
+
+#ifndef __ASSEMBLY__
+#include <linux/sched.h>
+#include <linux/threads.h>
+#include <asm/io.h> /* For sub-arch specific PPC_PIN_SIZE */
+
+extern unsigned long ioremap_bot;
+
+/*
+ * entries per page directory level: our page-table tree is two-level, so
+ * we don't really have any PMD directory.
+ */
+#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_SHIFT)
+#define PGD_TABLE_SIZE (sizeof(pgd_t) << (32 - PGDIR_SHIFT))
+
+#define pte_ERROR(e) \
+ pr_err("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
+ (unsigned long long)pte_val(e))
+#define pgd_ERROR(e) \
+ pr_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) PowerPC PTE as closely as possible.
+ */
+
+#define pte_clear(mm, addr, ptep) \
+ do { pte_update(ptep, ~_PAGE_HASHPTE, 0); } while (0)
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
+#define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ *pmdp = __pmd(0);
+}
+
+
+/*
+ * When flushing the tlb entry for a page, we also need to flush the hash
+ * table entry. flush_hash_pages is assembler (for speed) in hashtable.S.
+ */
+extern int flush_hash_pages(unsigned context, unsigned long va,
+ unsigned long pmdval, int count);
+
+/* Add an HPTE to the hash table */
+extern void add_hash_page(unsigned context, unsigned long va,
+ unsigned long pmdval);
+
+/* Flush an entry from the TLB/hash table */
+extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep,
+ unsigned long address);
+
+/*
+ * PTE updates. This function is called whenever an existing
+ * valid PTE is updated. This does -not- include set_pte_at()
+ * which nowadays only sets a new PTE.
+ *
+ * Depending on the type of MMU, we may need to use atomic updates
+ * and the PTE may be either 32 or 64 bit wide. In the later case,
+ * when using atomic updates, only the low part of the PTE is
+ * accessed atomically.
+ *
+ * In addition, on 44x, we also maintain a global flag indicating
+ * that an executable user mapping was modified, which is needed
+ * to properly flush the virtually tagged instruction cache of
+ * those implementations.
+ */
+#ifndef CONFIG_PTE_64BIT
+static inline unsigned long pte_update(pte_t *p,
+ unsigned long clr,
+ unsigned long set)
+{
+ unsigned long old, tmp;
+
+ __asm__ __volatile__("\
+1: lwarx %0,0,%3\n\
+ andc %1,%0,%4\n\
+ or %1,%1,%5\n"
+ PPC405_ERR77(0,%3)
+" stwcx. %1,0,%3\n\
+ bne- 1b"
+ : "=&r" (old), "=&r" (tmp), "=m" (*p)
+ : "r" (p), "r" (clr), "r" (set), "m" (*p)
+ : "cc" );
+
+ return old;
+}
+#else /* CONFIG_PTE_64BIT */
+static inline unsigned long long pte_update(pte_t *p,
+ unsigned long clr,
+ unsigned long set)
+{
+ unsigned long long old;
+ unsigned long tmp;
+
+ __asm__ __volatile__("\
+1: lwarx %L0,0,%4\n\
+ lwzx %0,0,%3\n\
+ andc %1,%L0,%5\n\
+ or %1,%1,%6\n"
+ PPC405_ERR77(0,%3)
+" stwcx. %1,0,%4\n\
+ bne- 1b"
+ : "=&r" (old), "=&r" (tmp), "=m" (*p)
+ : "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p)
+ : "cc" );
+
+ return old;
+}
+#endif /* CONFIG_PTE_64BIT */
+
+/*
+ * 2.6 calls this without flushing the TLB entry; this is wrong
+ * for our hash-based implementation, we fix that up here.
+ */
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
+static inline int __ptep_test_and_clear_young(unsigned int context, unsigned long addr, pte_t *ptep)
+{
+ unsigned long old;
+ old = pte_update(ptep, _PAGE_ACCESSED, 0);
+ if (old & _PAGE_HASHPTE) {
+ unsigned long ptephys = __pa(ptep) & PAGE_MASK;
+ flush_hash_pages(context, addr, ptephys, 1);
+ }
+ return (old & _PAGE_ACCESSED) != 0;
+}
+#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
+ __ptep_test_and_clear_young((__vma)->vm_mm->context.id, __addr, __ptep)
+
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+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));
+}
+
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), _PAGE_RO);
+}
+static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ ptep_set_wrprotect(mm, addr, ptep);
+}
+
+
+static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
+{
+ unsigned long set = pte_val(entry) &
+ (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
+ unsigned long clr = ~pte_val(entry) & _PAGE_RO;
+
+ pte_update(ptep, clr, set);
+}
+
+#define __HAVE_ARCH_PTE_SAME
+#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
+
+/*
+ * Note that on Book E processors, the pmd contains the kernel virtual
+ * (lowmem) address of the pte page. The physical address is less useful
+ * because everything runs with translation enabled (even the TLB miss
+ * handler). On everything else the pmd contains the physical address
+ * of the pte page. -- paulus
+ */
+#ifndef CONFIG_BOOKE
+#define pmd_page_vaddr(pmd) \
+ ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
+#define pmd_page(pmd) \
+ pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)
+#else
+#define pmd_page_vaddr(pmd) \
+ ((unsigned long) (pmd_val(pmd) & PAGE_MASK))
+#define pmd_page(pmd) \
+ pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
+#endif
+
+/* 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 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_vaddr(*(dir)) + pte_index(addr))
+#define pte_offset_map(dir, addr) \
+ ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr))
+#define pte_unmap(pte) kunmap_atomic(pte)
+
+/*
+ * 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 & 0x1f)
+#define __swp_offset(entry) ((entry).val >> 5)
+#define __swp_entry(type, offset) ((swp_entry_t) { (type) | ((offset) << 5) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
+
+#ifndef CONFIG_PPC_4K_PAGES
+void pgtable_cache_init(void);
+#else
+/*
+ * No page table caches to initialise
+ */
+#define pgtable_cache_init() do { } while (0)
+#endif
+
+extern int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep,
+ pmd_t **pmdp);
+
+/* Generic accessors to PTE bits */
+static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);}
+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); }
+static inline int pte_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); }
+static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
+static inline pgprot_t pte_pgprot(pte_t pte) { return __pgprot(pte_val(pte) & PAGE_PROT_BITS); }
+
+static inline int pte_present(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_PRESENT;
+}
+
+/* Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ *
+ * Even if PTEs can be unsigned long long, a PFN is always an unsigned
+ * long for now.
+ */
+static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
+{
+ return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |
+ pgprot_val(pgprot));
+}
+
+static inline unsigned long pte_pfn(pte_t pte)
+{
+ return pte_val(pte) >> PTE_RPN_SHIFT;
+}
+
+/* Generic modifiers for PTE bits */
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_RW);
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_DIRTY);
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
+}
+
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_RW);
+}
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_DIRTY);
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_ACCESSED);
+}
+
+static inline pte_t pte_mkspecial(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_SPECIAL);
+}
+
+static inline pte_t pte_mkhuge(pte_t pte)
+{
+ return pte;
+}
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+ return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
+}
+
+
+
+/* This low level function performs the actual PTE insertion
+ * Setting the PTE depends on the MMU type and other factors. It's
+ * an horrible mess that I'm not going to try to clean up now but
+ * I'm keeping it in one place rather than spread around
+ */
+static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, int percpu)
+{
+#if defined(CONFIG_PPC_STD_MMU_32) && defined(CONFIG_SMP) && !defined(CONFIG_PTE_64BIT)
+ /* First case is 32-bit Hash MMU in SMP mode with 32-bit PTEs. We use the
+ * helper pte_update() which does an atomic update. We need to do that
+ * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a
+ * per-CPU PTE such as a kmap_atomic, we do a simple update preserving
+ * the hash bits instead (ie, same as the non-SMP case)
+ */
+ if (percpu)
+ *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
+ | (pte_val(pte) & ~_PAGE_HASHPTE));
+ else
+ pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte));
+
+#elif defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
+ /* Second case is 32-bit with 64-bit PTE. In this case, we
+ * can just store as long as we do the two halves in the right order
+ * with a barrier in between. This is possible because we take care,
+ * in the hash code, to pre-invalidate if the PTE was already hashed,
+ * which synchronizes us with any concurrent invalidation.
+ * In the percpu case, we also fallback to the simple update preserving
+ * the hash bits
+ */
+ if (percpu) {
+ *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
+ | (pte_val(pte) & ~_PAGE_HASHPTE));
+ return;
+ }
+ if (pte_val(*ptep) & _PAGE_HASHPTE)
+ flush_hash_entry(mm, ptep, addr);
+ __asm__ __volatile__("\
+ stw%U0%X0 %2,%0\n\
+ eieio\n\
+ stw%U0%X0 %L2,%1"
+ : "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
+ : "r" (pte) : "memory");
+
+#elif defined(CONFIG_PPC_STD_MMU_32)
+ /* Third case is 32-bit hash table in UP mode, we need to preserve
+ * the _PAGE_HASHPTE bit since we may not have invalidated the previous
+ * translation in the hash yet (done in a subsequent flush_tlb_xxx())
+ * and see we need to keep track that this PTE needs invalidating
+ */
+ *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
+ | (pte_val(pte) & ~_PAGE_HASHPTE));
+
+#else
+#error "Not supported "
+#endif
+}
+
+/*
+ * Macro to mark a page protection value as "uncacheable".
+ */
+
+#define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \
+ _PAGE_WRITETHRU)
+
+#define pgprot_noncached pgprot_noncached
+static inline pgprot_t pgprot_noncached(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_NO_CACHE | _PAGE_GUARDED);
+}
+
+#define pgprot_noncached_wc pgprot_noncached_wc
+static inline pgprot_t pgprot_noncached_wc(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_NO_CACHE);
+}
+
+#define pgprot_cached pgprot_cached
+static inline pgprot_t pgprot_cached(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_COHERENT);
+}
+
+#define pgprot_cached_wthru pgprot_cached_wthru
+static inline pgprot_t pgprot_cached_wthru(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_COHERENT | _PAGE_WRITETHRU);
+}
+
+#define pgprot_cached_noncoherent pgprot_cached_noncoherent
+static inline pgprot_t pgprot_cached_noncoherent(pgprot_t prot)
+{
+ return __pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL);
+}
+
+#define pgprot_writecombine pgprot_writecombine
+static inline pgprot_t pgprot_writecombine(pgprot_t prot)
+{
+ return pgprot_noncached_wc(prot);
+}
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_BOOK3S_32_PGTABLE_H */