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+/*
+ * linux/arch/arm/mm/cache-v4wb.S
+ *
+ * Copyright (C) 1997-2002 Russell king
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/hardware.h>
+#include <asm/page.h>
+#include "proc-macros.S"
+
+/*
+ * The size of one data cache line.
+ */
+#define CACHE_DLINESIZE 32
+
+/*
+ * The total size of the data cache.
+ */
+#if defined(CONFIG_CPU_SA110)
+# define CACHE_DSIZE 16384
+#elif defined(CONFIG_CPU_SA1100)
+# define CACHE_DSIZE 8192
+#else
+# error Unknown cache size
+#endif
+
+/*
+ * This is the size at which it becomes more efficient to
+ * clean the whole cache, rather than using the individual
+ * cache line maintainence instructions.
+ *
+ * Size Clean (ticks) Dirty (ticks)
+ * 4096 21 20 21 53 55 54
+ * 8192 40 41 40 106 100 102
+ * 16384 77 77 76 140 140 138
+ * 32768 150 149 150 214 216 212 <---
+ * 65536 296 297 296 351 358 361
+ * 131072 591 591 591 656 657 651
+ * Whole 132 136 132 221 217 207 <---
+ */
+#define CACHE_DLIMIT (CACHE_DSIZE * 4)
+
+/*
+ * flush_user_cache_all()
+ *
+ * Clean and invalidate all cache entries in a particular address
+ * space.
+ */
+ENTRY(v4wb_flush_user_cache_all)
+ /* FALLTHROUGH */
+/*
+ * flush_kern_cache_all()
+ *
+ * Clean and invalidate the entire cache.
+ */
+ENTRY(v4wb_flush_kern_cache_all)
+ mov ip, #0
+ mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
+__flush_whole_cache:
+ mov r0, #FLUSH_BASE
+ add r1, r0, #CACHE_DSIZE
+1: ldr r2, [r0], #32
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, ip, c7, c10, 4 @ drain write buffer
+ mov pc, lr
+
+/*
+ * flush_user_cache_range(start, end, flags)
+ *
+ * Invalidate a range of cache entries in the specified
+ * address space.
+ *
+ * - start - start address (inclusive, page aligned)
+ * - end - end address (exclusive, page aligned)
+ * - flags - vma_area_struct flags describing address space
+ */
+ENTRY(v4wb_flush_user_cache_range)
+ sub r3, r1, r0 @ calculate total size
+ tst r2, #VM_EXEC @ executable region?
+ mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
+
+ cmp r3, #CACHE_DLIMIT @ total size >= limit?
+ bhs __flush_whole_cache @ flush whole D cache
+
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ tst r2, #VM_EXEC
+ mcrne p15, 0, ip, c7, c10, 4 @ drain write buffer
+ mov pc, lr
+
+/*
+ * flush_kern_dcache_page(void *page)
+ *
+ * Ensure no D cache aliasing occurs, either with itself or
+ * the I cache
+ *
+ * - addr - page aligned address
+ */
+ENTRY(v4wb_flush_kern_dcache_page)
+ add r1, r0, #PAGE_SZ
+ /* fall through */
+
+/*
+ * coherent_kern_range(start, end)
+ *
+ * Ensure coherency between the Icache and the Dcache in the
+ * region described by start. If you have non-snooping
+ * Harvard caches, you need to implement this function.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(v4wb_coherent_kern_range)
+ /* fall through */
+
+/*
+ * coherent_user_range(start, end)
+ *
+ * Ensure coherency between the Icache and the Dcache in the
+ * region described by start. If you have non-snooping
+ * Harvard caches, you need to implement this function.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(v4wb_coherent_user_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mov ip, #0
+ mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
+ mcr p15, 0, ip, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+
+/*
+ * dma_inv_range(start, end)
+ *
+ * Invalidate (discard) the specified virtual address range.
+ * May not write back any entries. If 'start' or 'end'
+ * are not cache line aligned, those lines must be written
+ * back.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(v4wb_dma_inv_range)
+ tst r0, #CACHE_DLINESIZE - 1
+ bic r0, r0, #CACHE_DLINESIZE - 1
+ mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
+ tst r1, #CACHE_DLINESIZE - 1
+ mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
+1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
+ mov pc, lr
+
+/*
+ * dma_clean_range(start, end)
+ *
+ * Clean (write back) the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(v4wb_dma_clean_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
+ mov pc, lr
+
+/*
+ * dma_flush_range(start, end)
+ *
+ * Clean and invalidate the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ *
+ * This is actually the same as v4wb_coherent_kern_range()
+ */
+ .globl v4wb_dma_flush_range
+ .set v4wb_dma_flush_range, v4wb_coherent_kern_range
+
+ __INITDATA
+
+ .type v4wb_cache_fns, #object
+ENTRY(v4wb_cache_fns)
+ .long v4wb_flush_kern_cache_all
+ .long v4wb_flush_user_cache_all
+ .long v4wb_flush_user_cache_range
+ .long v4wb_coherent_kern_range
+ .long v4wb_coherent_user_range
+ .long v4wb_flush_kern_dcache_page
+ .long v4wb_dma_inv_range
+ .long v4wb_dma_clean_range
+ .long v4wb_dma_flush_range
+ .size v4wb_cache_fns, . - v4wb_cache_fns