1 files changed, 125 insertions, 0 deletions
diff --git a/arch/tile/include/asm/homecache.h b/arch/tile/include/asm/homecache.h
new file mode 100644
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+++ b/arch/tile/include/asm/homecache.h
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+/*
+ * 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.
+ *
+ * Handle issues around the Tile "home cache" model of coherence.
+ */
+
+#ifndef _ASM_TILE_HOMECACHE_H
+#define _ASM_TILE_HOMECACHE_H
+
+#include <asm/page.h>
+#include <linux/cpumask.h>
+
+struct page;
+struct task_struct;
+struct vm_area_struct;
+struct zone;
+
+/*
+ * Coherence point for the page is its memory controller.
+ * It is not present in any cache (L1 or L2).
+ */
+#define PAGE_HOME_UNCACHED -1
+
+/*
+ * Is this page immutable (unwritable) and thus able to be cached more
+ * widely than would otherwise be possible?  On tile64 this means we
+ * mark the PTE to cache locally; on tilepro it means we have "nc" set.
+ */
+#define PAGE_HOME_IMMUTABLE -2
+
+/*
+ * Each cpu considers its own cache to be the home for the page,
+ * which makes it incoherent.
+ */
+#define PAGE_HOME_INCOHERENT -3
+
+#if CHIP_HAS_CBOX_HOME_MAP()
+/* Home for the page is distributed via hash-for-home. */
+#define PAGE_HOME_HASH -4
+#endif
+
+/* Homing is unknown or unspecified.  Not valid for page_home(). */
+#define PAGE_HOME_UNKNOWN -5
+
+/* Home on the current cpu.  Not valid for page_home(). */
+#define PAGE_HOME_HERE -6
+
+/* Support wrapper to use instead of explicit hv_flush_remote(). */
+extern void flush_remote(unsigned long cache_pfn, unsigned long cache_length,
+			 const struct cpumask *cache_cpumask,
+			 HV_VirtAddr tlb_va, unsigned long tlb_length,
+			 unsigned long tlb_pgsize,
+			 const struct cpumask *tlb_cpumask,
+			 HV_Remote_ASID *asids, int asidcount);
+
+/* Set homing-related bits in a PTE (can also pass a pgprot_t). */
+extern pte_t pte_set_home(pte_t pte, int home);
+
+/* Do a cache eviction on the specified cpus. */
+extern void homecache_evict(const struct cpumask *mask);
+
+/*
+ * Change a kernel page's homecache.  It must not be mapped in user space.
+ * If !CONFIG_HOMECACHE, only usable on LOWMEM, and can only be called when
+ * no other cpu can reference the page, and causes a full-chip cache/TLB flush.
+ */
+extern void homecache_change_page_home(struct page *, int order, int home);
+
+/*
+ * Flush a page out of whatever cache(s) it is in.
+ * This is more than just finv, since it properly handles waiting
+ * for the data to reach memory on tilepro, but it can be quite
+ * heavyweight, particularly on hash-for-home memory.
+ */
+extern void homecache_flush_cache(struct page *, int order);
+
+/*
+ * Allocate a page with the given GFP flags, home, and optionally
+ * node.  These routines are actually just wrappers around the normal
+ * alloc_pages() / alloc_pages_node() functions, which set and clear
+ * a per-cpu variable to communicate with homecache_new_kernel_page().
+ * If !CONFIG_HOMECACHE, uses homecache_change_page_home().
+ */
+extern struct page *homecache_alloc_pages(gfp_t gfp_mask,
+					  unsigned int order, int home);
+extern struct page *homecache_alloc_pages_node(int nid, gfp_t gfp_mask,
+					       unsigned int order, int home);
+#define homecache_alloc_page(gfp_mask, home) \
+  homecache_alloc_pages(gfp_mask, 0, home)
+
+/*
+ * These routines are just pass-throughs to free_pages() when
+ * we support full homecaching.  If !CONFIG_HOMECACHE, then these
+ * routines use homecache_change_page_home() to reset the home
+ * back to the default before returning the page to the allocator.
+ */
+void homecache_free_pages(unsigned long addr, unsigned int order);
+#define homecache_free_page(page) \
+  homecache_free_pages((page), 0)
+
+
+
+/*
+ * Report the page home for LOWMEM pages by examining their kernel PTE,
+ * or for highmem pages as the default home.
+ */
+extern int page_home(struct page *);
+
+#define homecache_migrate_kthread() do {} while (0)
+
+#define homecache_kpte_lock() 0
+#define homecache_kpte_unlock(flags) do {} while (0)
+
+
+#endif /* _ASM_TILE_HOMECACHE_H */