ARC: Cache Flush Management

* ARC700 has VIPT L1 Caches
* Caches don't snoop and are not coherent
* Given the PAGE_SIZE and Cache associativity, we don't support aliasing
  D$ configurations (yet), but do allow aliasing I$ configs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/arch/arc/include/asm/cacheflush.h b/arch/arc/include/asm/cacheflush.h
new file mode 100644
index 000000000000..97ee96f26505
--- /dev/null
+++ b/arch/arc/include/asm/cacheflush.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ *
+ *  vineetg: May 2011: for Non-aliasing VIPT D-cache following can be NOPs
+ *   -flush_cache_dup_mm (fork)
+ *   -likewise for flush_cache_mm (exit/execve)
+ *   -likewise for flush_cache_{range,page} (munmap, exit, COW-break)
+ *
+ *  vineetg: April 2008
+ *   -Added a critical CacheLine flush to copy_to_user_page( ) which
+ *     was causing gdbserver to not setup breakpoints consistently
+ */
+
+#ifndef _ASM_CACHEFLUSH_H
+#define _ASM_CACHEFLUSH_H
+
+#include <linux/mm.h>
+
+void flush_cache_all(void);
+
+void flush_icache_range(unsigned long start, unsigned long end);
+void flush_icache_page(struct vm_area_struct *vma, struct page *page);
+void flush_icache_range_vaddr(unsigned long paddr, unsigned long u_vaddr,
+                                     int len);
+
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+
+void flush_dcache_page(struct page *page);
+
+void dma_cache_wback_inv(unsigned long start, unsigned long sz);
+void dma_cache_inv(unsigned long start, unsigned long sz);
+void dma_cache_wback(unsigned long start, unsigned long sz);
+
+#define flush_dcache_mmap_lock(mapping)         do { } while (0)
+#define flush_dcache_mmap_unlock(mapping)       do { } while (0)
+
+/* TBD: optimize this */
+#define flush_cache_vmap(start, end)            flush_cache_all()
+#define flush_cache_vunmap(start, end)          flush_cache_all()
+
+/*
+ * VM callbacks when entire/range of user-space V-P mappings are
+ * torn-down/get-invalidated
+ *
+ * Currently we don't support D$ aliasing configs for our VIPT caches
+ * NOPS for VIPT Cache with non-aliasing D$ configurations only
+ */
+#define flush_cache_dup_mm(mm)                  /* called on fork */
+#define flush_cache_mm(mm)                      /* called on munmap/exit */
+#define flush_cache_range(mm, u_vstart, u_vend)
+#define flush_cache_page(vma, u_vaddr, pfn)     /* PF handling/COW-break */
+
+#define copy_to_user_page(vma, page, vaddr, dst, src, len)              \
+do {                                                                    \
+        memcpy(dst, src, len);                                          \
+        if (vma->vm_flags & VM_EXEC)                                    \
+                flush_icache_range_vaddr((unsigned long)(dst), vaddr, len);\
+} while (0)
+
+#define copy_from_user_page(vma, page, vaddr, dst, src, len)            \
+        memcpy(dst, src, len);                                          \
+
+#endif