Initial import

1 files changed, 484 insertions, 0 deletions

diff --git a/arch/xtensa/mm/misc.S b/arch/xtensa/mm/misc.S
new file mode 100644
index 000000000..11a01c3e9
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+++ b/arch/xtensa/mm/misc.S
@@ -0,0 +1,484 @@
+/*
+ * arch/xtensa/mm/misc.S
+ *
+ * Miscellaneous assembly functions.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2007 Tensilica Inc.
+ *
+ * Chris Zankel	<chris@zankel.net>
+ */
+
+
+#include <linux/linkage.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/asmmacro.h>
+#include <asm/cacheasm.h>
+#include <asm/tlbflush.h>
+
+
+/*
+ * clear_page and clear_user_page are the same for non-cache-aliased configs.
+ *
+ * clear_page (unsigned long page)
+ *                    a2
+ */
+
+ENTRY(clear_page)
+
+	entry	a1, 16
+
+	movi	a3, 0
+	__loopi	a2, a7, PAGE_SIZE, 32
+	s32i	a3, a2, 0
+	s32i	a3, a2, 4
+	s32i	a3, a2, 8
+	s32i	a3, a2, 12
+	s32i	a3, a2, 16
+	s32i	a3, a2, 20
+	s32i	a3, a2, 24
+	s32i	a3, a2, 28
+	__endla	a2, a7, 32
+
+	retw
+
+ENDPROC(clear_page)
+
+/*
+ * copy_page and copy_user_page are the same for non-cache-aliased configs.
+ *
+ * copy_page (void *to, void *from)
+ *               a2          a3
+ */
+
+ENTRY(copy_page)
+
+	entry	a1, 16
+
+	__loopi a2, a4, PAGE_SIZE, 32
+
+	l32i    a8, a3, 0
+	l32i    a9, a3, 4
+	s32i    a8, a2, 0
+	s32i    a9, a2, 4
+
+	l32i    a8, a3, 8
+	l32i    a9, a3, 12
+	s32i    a8, a2, 8
+	s32i    a9, a2, 12
+
+	l32i    a8, a3, 16
+	l32i    a9, a3, 20
+	s32i    a8, a2, 16
+	s32i    a9, a2, 20
+
+	l32i    a8, a3, 24
+	l32i    a9, a3, 28
+	s32i    a8, a2, 24
+	s32i    a9, a2, 28
+
+	addi    a2, a2, 32
+	addi    a3, a3, 32
+
+	__endl  a2, a4
+
+	retw
+
+ENDPROC(copy_page)
+
+#ifdef CONFIG_MMU
+/*
+ * If we have to deal with cache aliasing, we use temporary memory mappings
+ * to ensure that the source and destination pages have the same color as
+ * the virtual address. We use way 0 and 1 for temporary mappings in such cases.
+ *
+ * The temporary DTLB entries shouldn't be flushed by interrupts, but are
+ * flushed by preemptive task switches. Special code in the 
+ * fast_second_level_miss handler re-established the temporary mapping. 
+ * It requires that the PPNs for the destination and source addresses are
+ * in a6, and a7, respectively.
+ */
+
+/* TLB miss exceptions are treated special in the following region */
+
+ENTRY(__tlbtemp_mapping_start)
+
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+
+/*
+ * clear_page_alias(void *addr, unsigned long paddr)
+ *                     a2              a3
+ */
+
+ENTRY(clear_page_alias)
+
+	entry	a1, 32
+
+	/* Skip setting up a temporary DTLB if not aliased low page. */
+
+	movi	a5, PAGE_OFFSET
+	movi	a6, 0
+	beqz	a3, 1f
+
+	/* Setup a temporary DTLB for the addr. */
+
+	addi	a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+	mov	a4, a2
+	wdtlb	a6, a2
+	dsync
+
+1:	movi	a3, 0
+	__loopi	a2, a7, PAGE_SIZE, 32
+	s32i	a3, a2, 0
+	s32i	a3, a2, 4
+	s32i	a3, a2, 8
+	s32i	a3, a2, 12
+	s32i	a3, a2, 16
+	s32i	a3, a2, 20
+	s32i	a3, a2, 24
+	s32i	a3, a2, 28
+	__endla	a2, a7, 32
+
+	bnez	a6, 1f
+	retw
+
+	/* We need to invalidate the temporary idtlb entry, if any. */
+
+1:	idtlb	a4
+	dsync
+
+	retw
+
+ENDPROC(clear_page_alias)
+
+/*
+ * copy_page_alias(void *to, void *from,
+ *			a2	  a3
+ *                 unsigned long to_paddr, unsigned long from_paddr)
+ *	        		 a4			 a5
+ */
+
+ENTRY(copy_page_alias)
+
+	entry	a1, 32
+
+	/* Skip setting up a temporary DTLB for destination if not aliased. */
+
+	movi	a6, 0
+	movi	a7, 0
+	beqz	a4, 1f
+
+	/* Setup a temporary DTLB for destination. */
+
+	addi	a6, a4, (PAGE_KERNEL | _PAGE_HW_WRITE)
+	wdtlb	a6, a2
+	dsync
+
+	/* Skip setting up a temporary DTLB for source if not aliased. */
+
+1:	beqz	a5, 1f
+
+	/* Setup a temporary DTLB for source. */
+
+	addi	a7, a5, PAGE_KERNEL
+	addi	a8, a3, 1				# way1
+
+	wdtlb	a7, a8
+	dsync
+
+1:	__loopi a2, a4, PAGE_SIZE, 32
+
+	l32i    a8, a3, 0
+	l32i    a9, a3, 4
+	s32i    a8, a2, 0
+	s32i    a9, a2, 4
+
+	l32i    a8, a3, 8
+	l32i    a9, a3, 12
+	s32i    a8, a2, 8
+	s32i    a9, a2, 12
+
+	l32i    a8, a3, 16
+	l32i    a9, a3, 20
+	s32i    a8, a2, 16
+	s32i    a9, a2, 20
+
+	l32i    a8, a3, 24
+	l32i    a9, a3, 28
+	s32i    a8, a2, 24
+	s32i    a9, a2, 28
+
+	addi    a2, a2, 32
+	addi    a3, a3, 32
+
+	__endl  a2, a4
+
+	/* We need to invalidate any temporary mapping! */
+
+	bnez	a6, 1f
+	bnez	a7, 2f
+	retw
+
+1:	addi	a2, a2, -PAGE_SIZE
+	idtlb	a2
+	dsync
+	bnez	a7, 2f
+	retw
+
+2:	addi	a3, a3, -PAGE_SIZE+1
+	idtlb	a3
+	dsync
+
+	retw
+
+ENDPROC(copy_page_alias)
+
+#endif
+
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+
+/*
+ * void __flush_invalidate_dcache_page_alias (addr, phys)
+ *                                             a2    a3
+ */
+
+ENTRY(__flush_invalidate_dcache_page_alias)
+
+	entry	sp, 16
+
+	movi	a7, 0			# required for exception handler
+	addi	a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+	mov	a4, a2
+	wdtlb	a6, a2
+	dsync
+
+	___flush_invalidate_dcache_page a2 a3
+
+	idtlb	a4
+	dsync
+
+	retw
+
+ENDPROC(__flush_invalidate_dcache_page_alias)
+
+/*
+ * void __invalidate_dcache_page_alias (addr, phys)
+ *                                       a2    a3
+ */
+
+ENTRY(__invalidate_dcache_page_alias)
+
+	entry	sp, 16
+
+	movi	a7, 0			# required for exception handler
+	addi	a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+	mov	a4, a2
+	wdtlb	a6, a2
+	dsync
+
+	___invalidate_dcache_page a2 a3
+
+	idtlb	a4
+	dsync
+
+	retw
+
+ENDPROC(__invalidate_dcache_page_alias)
+#endif
+
+ENTRY(__tlbtemp_mapping_itlb)
+
+#if (ICACHE_WAY_SIZE > PAGE_SIZE)
+	
+ENTRY(__invalidate_icache_page_alias)
+
+	entry	sp, 16
+
+	addi	a6, a3, (PAGE_KERNEL_EXEC | _PAGE_HW_WRITE)
+	mov	a4, a2
+	witlb	a6, a2
+	isync
+
+	___invalidate_icache_page a2 a3
+
+	iitlb	a4
+	isync
+	retw
+
+ENDPROC(__invalidate_icache_page_alias)
+
+#endif
+
+/* End of special treatment in tlb miss exception */
+
+ENTRY(__tlbtemp_mapping_end)
+
+#endif /* CONFIG_MMU
+
+/*
+ * void __invalidate_icache_page(ulong start)
+ */
+
+ENTRY(__invalidate_icache_page)
+
+	entry	sp, 16
+
+	___invalidate_icache_page a2 a3
+	isync
+
+	retw
+
+ENDPROC(__invalidate_icache_page)
+
+/*
+ * void __invalidate_dcache_page(ulong start)
+ */
+
+ENTRY(__invalidate_dcache_page)
+
+	entry	sp, 16
+
+	___invalidate_dcache_page a2 a3
+	dsync
+
+	retw
+
+ENDPROC(__invalidate_dcache_page)
+
+/*
+ * void __flush_invalidate_dcache_page(ulong start)
+ */
+
+ENTRY(__flush_invalidate_dcache_page)
+
+	entry	sp, 16
+
+	___flush_invalidate_dcache_page a2 a3
+
+	dsync
+	retw
+
+ENDPROC(__flush_invalidate_dcache_page)
+
+/*
+ * void __flush_dcache_page(ulong start)
+ */
+
+ENTRY(__flush_dcache_page)
+
+	entry	sp, 16
+
+	___flush_dcache_page a2 a3
+
+	dsync
+	retw
+
+ENDPROC(__flush_dcache_page)
+
+/*
+ * void __invalidate_icache_range(ulong start, ulong size)
+ */
+
+ENTRY(__invalidate_icache_range)
+
+	entry	sp, 16
+
+	___invalidate_icache_range a2 a3 a4
+	isync
+
+	retw
+
+ENDPROC(__invalidate_icache_range)
+
+/*
+ * void __flush_invalidate_dcache_range(ulong start, ulong size)
+ */
+
+ENTRY(__flush_invalidate_dcache_range)
+
+	entry	sp, 16
+
+	___flush_invalidate_dcache_range a2 a3 a4
+	dsync
+
+	retw
+
+ENDPROC(__flush_invalidate_dcache_range)
+
+/*
+ * void _flush_dcache_range(ulong start, ulong size)
+ */
+
+ENTRY(__flush_dcache_range)
+
+	entry	sp, 16
+
+	___flush_dcache_range a2 a3 a4
+	dsync
+
+	retw
+
+ENDPROC(__flush_dcache_range)
+
+/*
+ * void _invalidate_dcache_range(ulong start, ulong size)
+ */
+
+ENTRY(__invalidate_dcache_range)
+
+	entry	sp, 16
+
+	___invalidate_dcache_range a2 a3 a4
+
+	retw
+
+ENDPROC(__invalidate_dcache_range)
+
+/*
+ * void _invalidate_icache_all(void)
+ */
+
+ENTRY(__invalidate_icache_all)
+
+	entry	sp, 16
+
+	___invalidate_icache_all a2 a3
+	isync
+
+	retw
+
+ENDPROC(__invalidate_icache_all)
+
+/*
+ * void _flush_invalidate_dcache_all(void)
+ */
+
+ENTRY(__flush_invalidate_dcache_all)
+
+	entry	sp, 16
+
+	___flush_invalidate_dcache_all a2 a3
+	dsync
+
+	retw
+
+ENDPROC(__flush_invalidate_dcache_all)
+
+/*
+ * void _invalidate_dcache_all(void)
+ */
+
+ENTRY(__invalidate_dcache_all)
+
+	entry	sp, 16
+
+	___invalidate_dcache_all a2 a3
+	dsync
+
+	retw
+
+ENDPROC(__invalidate_dcache_all)