1 files changed, 203 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h
new file mode 100644
index 0000000000..a77d04972e
--- /dev/null
+++ b/arch/xtensa/include/asm/page.h
@@ -0,0 +1,203 @@
+/*
+ * include/asm-xtensa/page.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version2 as
+ * published by the Free Software Foundation.
+ *
+ * Copyright (C) 2001 - 2007 Tensilica Inc.
+ */
+
+#ifndef _XTENSA_PAGE_H
+#define _XTENSA_PAGE_H
+
+#include <linux/const.h>
+
+#include <asm/processor.h>
+#include <asm/types.h>
+#include <asm/cache.h>
+#include <asm/kmem_layout.h>
+
+/*
+ * PAGE_SHIFT determines the page size
+ */
+
+#define PAGE_SHIFT	12
+#define PAGE_SIZE	(__XTENSA_UL_CONST(1) << PAGE_SHIFT)
+#define PAGE_MASK	(~(PAGE_SIZE-1))
+
+#ifdef CONFIG_MMU
+#define PAGE_OFFSET	XCHAL_KSEG_CACHED_VADDR
+#define PHYS_OFFSET	XCHAL_KSEG_PADDR
+#define MAX_LOW_PFN	(PHYS_PFN(XCHAL_KSEG_PADDR) + \
+			 PHYS_PFN(XCHAL_KSEG_SIZE))
+#else
+#define PAGE_OFFSET	_AC(CONFIG_DEFAULT_MEM_START, UL)
+#define PHYS_OFFSET	_AC(CONFIG_DEFAULT_MEM_START, UL)
+#define MAX_LOW_PFN	PHYS_PFN(0xfffffffful)
+#endif
+
+/*
+ * Cache aliasing:
+ *
+ * If the cache size for one way is greater than the page size, we have to
+ * deal with cache aliasing. The cache index is wider than the page size:
+ *
+ * |    |cache| cache index
+ * | pfn  |off|	virtual address
+ * |xxxx:X|zzz|
+ * |    : |   |
+ * | \  / |   |
+ * |trans.|   |
+ * | /  \ |   |
+ * |yyyy:Y|zzz|	physical address
+ *
+ * When the page number is translated to the physical page address, the lowest
+ * bit(s) (X) that are part of the cache index are also translated (Y).
+ * If this translation changes bit(s) (X), the cache index is also afected,
+ * thus resulting in a different cache line than before.
+ * The kernel does not provide a mechanism to ensure that the page color
+ * (represented by this bit) remains the same when allocated or when pages
+ * are remapped. When user pages are mapped into kernel space, the color of
+ * the page might also change.
+ *
+ * We use the address space VMALLOC_END ... VMALLOC_END + DCACHE_WAY_SIZE * 2
+ * to temporarily map a patch so we can match the color.
+ */
+
+#if DCACHE_WAY_SIZE > PAGE_SIZE
+# define DCACHE_ALIAS_ORDER	(DCACHE_WAY_SHIFT - PAGE_SHIFT)
+# define DCACHE_ALIAS_MASK	(PAGE_MASK & (DCACHE_WAY_SIZE - 1))
+# define DCACHE_ALIAS(a)	(((a) & DCACHE_ALIAS_MASK) >> PAGE_SHIFT)
+# define DCACHE_ALIAS_EQ(a,b)	((((a) ^ (b)) & DCACHE_ALIAS_MASK) == 0)
+#else
+# define DCACHE_ALIAS_ORDER	0
+# define DCACHE_ALIAS(a)	((void)(a), 0)
+#endif
+#define DCACHE_N_COLORS		(1 << DCACHE_ALIAS_ORDER)
+
+#if ICACHE_WAY_SIZE > PAGE_SIZE
+# define ICACHE_ALIAS_ORDER	(ICACHE_WAY_SHIFT - PAGE_SHIFT)
+# define ICACHE_ALIAS_MASK	(PAGE_MASK & (ICACHE_WAY_SIZE - 1))
+# define ICACHE_ALIAS(a)	(((a) & ICACHE_ALIAS_MASK) >> PAGE_SHIFT)
+# define ICACHE_ALIAS_EQ(a,b)	((((a) ^ (b)) & ICACHE_ALIAS_MASK) == 0)
+#else
+# define ICACHE_ALIAS_ORDER	0
+#endif
+
+
+#ifdef __ASSEMBLY__
+
+#define __pgprot(x)	(x)
+
+#else
+
+/*
+ * These are used to make use of C type-checking..
+ */
+
+typedef struct { unsigned long pte; } pte_t;		/* page table entry */
+typedef struct { unsigned long pgd; } pgd_t;		/* PGD table entry */
+typedef struct { unsigned long pgprot; } pgprot_t;
+typedef struct page *pgtable_t;
+
+#define pte_val(x)	((x).pte)
+#define pgd_val(x)	((x).pgd)
+#define pgprot_val(x)	((x).pgprot)
+
+#define __pte(x)	((pte_t) { (x) } )
+#define __pgd(x)	((pgd_t) { (x) } )
+#define __pgprot(x)	((pgprot_t) { (x) } )
+
+/*
+ * Pure 2^n version of get_order
+ * Use 'nsau' instructions if supported by the processor or the generic version.
+ */
+
+#if XCHAL_HAVE_NSA
+
+static inline __attribute_const__ int get_order(unsigned long size)
+{
+	int lz;
+	asm ("nsau %0, %1" : "=r" (lz) : "r" ((size - 1) >> PAGE_SHIFT));
+	return 32 - lz;
+}
+
+#else
+
+# include <asm-generic/getorder.h>
+
+#endif
+
+struct page;
+struct vm_area_struct;
+extern void clear_page(void *page);
+extern void copy_page(void *to, void *from);
+
+/*
+ * If we have cache aliasing and writeback caches, we might have to do
+ * some extra work
+ */
+
+#if defined(CONFIG_MMU) && DCACHE_WAY_SIZE > PAGE_SIZE
+extern void clear_page_alias(void *vaddr, unsigned long paddr);
+extern void copy_page_alias(void *to, void *from,
+			    unsigned long to_paddr, unsigned long from_paddr);
+
+#define clear_user_highpage clear_user_highpage
+void clear_user_highpage(struct page *page, unsigned long vaddr);
+#define __HAVE_ARCH_COPY_USER_HIGHPAGE
+void copy_user_highpage(struct page *to, struct page *from,
+			unsigned long vaddr, struct vm_area_struct *vma);
+#else
+# define clear_user_page(page, vaddr, pg)	clear_page(page)
+# define copy_user_page(to, from, vaddr, pg)	copy_page(to, from)
+#endif
+
+/*
+ * This handles the memory map.  We handle pages at
+ * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space.
+ * These macros are for conversion of kernel address, not user
+ * addresses.
+ */
+
+#define ARCH_PFN_OFFSET		(PHYS_OFFSET >> PAGE_SHIFT)
+
+#ifdef CONFIG_MMU
+static inline unsigned long ___pa(unsigned long va)
+{
+	unsigned long off = va - PAGE_OFFSET;
+
+	if (off >= XCHAL_KSEG_SIZE)
+		off -= XCHAL_KSEG_SIZE;
+
+#ifndef CONFIG_XIP_KERNEL
+	return off + PHYS_OFFSET;
+#else
+	if (off < XCHAL_KSEG_SIZE)
+		return off + PHYS_OFFSET;
+
+	off -= XCHAL_KSEG_SIZE;
+	if (off >= XCHAL_KIO_SIZE)
+		off -= XCHAL_KIO_SIZE;
+
+	return off + XCHAL_KIO_PADDR;
+#endif
+}
+#define __pa(x)	___pa((unsigned long)(x))
+#else
+#define __pa(x)	\
+	((unsigned long) (x) - PAGE_OFFSET + PHYS_OFFSET)
+#endif
+#define __va(x)	\
+	((void *)((unsigned long) (x) - PHYS_OFFSET + PAGE_OFFSET))
+
+#define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
+#define page_to_virt(page)	__va(page_to_pfn(page) << PAGE_SHIFT)
+#define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+#define page_to_phys(page)	(page_to_pfn(page) << PAGE_SHIFT)
+
+#endif /* __ASSEMBLY__ */
+
+#include <asm-generic/memory_model.h>
+#endif /* _XTENSA_PAGE_H */