arch/tile: core support for Tilera 32-bit chips.

This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.

This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 117 insertions, 0 deletions

diff --git a/arch/tile/include/asm/pgtable_32.h b/arch/tile/include/asm/pgtable_32.h
new file mode 100644
index 000000000000..b935fb2ad4f3
--- /dev/null
+++ b/arch/tile/include/asm/pgtable_32.h
@@ -0,0 +1,117 @@
+/*
+ * 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_PGTABLE_32_H
+#define _ASM_TILE_PGTABLE_32_H
+
+/*
+ * The level-1 index is defined by the huge page size.  A PGD is composed
+ * of PTRS_PER_PGD pgd_t's and is the top level of the page table.
+ */
+#define PGDIR_SHIFT	HV_LOG2_PAGE_SIZE_LARGE
+#define PGDIR_SIZE	HV_PAGE_SIZE_LARGE
+#define PGDIR_MASK	(~(PGDIR_SIZE-1))
+#define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
+
+/*
+ * The level-2 index is defined by the difference between the huge
+ * page size and the normal page size.  A PTE is composed of
+ * PTRS_PER_PTE pte_t's and is the bottom level of the page table.
+ * Note that the hypervisor docs use PTE for what we call pte_t, so
+ * this nomenclature is somewhat confusing.
+ */
+#define PTRS_PER_PTE (1 << (HV_LOG2_PAGE_SIZE_LARGE - HV_LOG2_PAGE_SIZE_SMALL))
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Right now we initialize only a single pte table. It can be extended
+ * easily, subsequent pte tables have to be allocated in one physical
+ * chunk of RAM.
+ *
+ * HOWEVER, if we are using an allocation scheme with slop after the
+ * end of the page table (e.g. where our L2 page tables are 2KB but
+ * our pages are 64KB and we are allocating via the page allocator)
+ * we can't extend it easily.
+ */
+#define LAST_PKMAP PTRS_PER_PTE
+
+#define PKMAP_BASE   ((FIXADDR_BOOT_START - PAGE_SIZE*LAST_PKMAP) & PGDIR_MASK)
+
+#ifdef CONFIG_HIGHMEM
+# define __VMAPPING_END	(PKMAP_BASE & ~(HPAGE_SIZE-1))
+#else
+# define __VMAPPING_END	(FIXADDR_START & ~(HPAGE_SIZE-1))
+#endif
+
+#ifdef CONFIG_HUGEVMAP
+#define HUGE_VMAP_END	__VMAPPING_END
+#define HUGE_VMAP_BASE	(HUGE_VMAP_END - CONFIG_NR_HUGE_VMAPS * HPAGE_SIZE)
+#define _VMALLOC_END	HUGE_VMAP_BASE
+#else
+#define _VMALLOC_END	__VMAPPING_END
+#endif
+
+/*
+ * Align the vmalloc area to an L2 page table, and leave a guard page
+ * at the beginning and end.  The vmalloc code also puts in an internal
+ * guard page between each allocation.
+ */
+#define VMALLOC_END	(_VMALLOC_END - PAGE_SIZE)
+extern unsigned long VMALLOC_RESERVE /* = CONFIG_VMALLOC_RESERVE */;
+#define _VMALLOC_START	(_VMALLOC_END - VMALLOC_RESERVE)
+#define VMALLOC_START	(_VMALLOC_START + PAGE_SIZE)
+
+/* This is the maximum possible amount of lowmem. */
+#define MAXMEM		(_VMALLOC_START - PAGE_OFFSET)
+
+/* We have no pmd or pud since we are strictly a two-level page table */
+#include <asm-generic/pgtable-nopmd.h>
+
+/* We don't define any pgds for these addresses. */
+static inline int pgd_addr_invalid(unsigned long addr)
+{
+	return addr >= MEM_HV_INTRPT;
+}
+
+/*
+ * Provide versions of these routines that can be used safely when
+ * the hypervisor may be asynchronously modifying dirty/accessed bits.
+ */
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+
+extern int ptep_test_and_clear_young(struct vm_area_struct *,
+				     unsigned long addr, pte_t *);
+extern void ptep_set_wrprotect(struct mm_struct *,
+			       unsigned long addr, pte_t *);
+
+/* Create a pmd from a PTFN. */
+static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
+{
+	return (pmd_t){ { hv_pte_set_ptfn(prot, ptfn) } };
+}
+
+/* Return the page-table frame number (ptfn) that a pmd_t points at. */
+#define pmd_ptfn(pmd) hv_pte_get_ptfn((pmd).pud.pgd)
+
+static inline void pmd_clear(pmd_t *pmdp)
+{
+	__pte_clear(&pmdp->pud.pgd);
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_TILE_PGTABLE_32_H */