1 /* 2 * Copyright 2010 Tilera Corporation. All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation, version 2. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 11 * NON INFRINGEMENT. See the GNU General Public License for 12 * more details. 13 * 14 * Handle issues around the Tile "home cache" model of coherence. 15 */ 16 17 #ifndef _ASM_TILE_HOMECACHE_H 18 #define _ASM_TILE_HOMECACHE_H 19 20 #include <asm/page.h> 21 #include <linux/cpumask.h> 22 23 struct page; 24 struct task_struct; 25 struct vm_area_struct; 26 struct zone; 27 28 /* 29 * Coherence point for the page is its memory controller. 30 * It is not present in any cache (L1 or L2). 31 */ 32 #define PAGE_HOME_UNCACHED -1 33 34 /* 35 * Is this page immutable (unwritable) and thus able to be cached more 36 * widely than would otherwise be possible? On tile64 this means we 37 * mark the PTE to cache locally; on tilepro it means we have "nc" set. 38 */ 39 #define PAGE_HOME_IMMUTABLE -2 40 41 /* 42 * Each cpu considers its own cache to be the home for the page, 43 * which makes it incoherent. 44 */ 45 #define PAGE_HOME_INCOHERENT -3 46 47 #if CHIP_HAS_CBOX_HOME_MAP() 48 /* Home for the page is distributed via hash-for-home. */ 49 #define PAGE_HOME_HASH -4 50 #endif 51 52 /* Homing is unknown or unspecified. Not valid for page_home(). */ 53 #define PAGE_HOME_UNKNOWN -5 54 55 /* Home on the current cpu. Not valid for page_home(). */ 56 #define PAGE_HOME_HERE -6 57 58 /* Support wrapper to use instead of explicit hv_flush_remote(). */ 59 extern void flush_remote(unsigned long cache_pfn, unsigned long cache_length, 60 const struct cpumask *cache_cpumask, 61 HV_VirtAddr tlb_va, unsigned long tlb_length, 62 unsigned long tlb_pgsize, 63 const struct cpumask *tlb_cpumask, 64 HV_Remote_ASID *asids, int asidcount); 65 66 /* Set homing-related bits in a PTE (can also pass a pgprot_t). */ 67 extern pte_t pte_set_home(pte_t pte, int home); 68 69 /* Do a cache eviction on the specified cpus. */ 70 extern void homecache_evict(const struct cpumask *mask); 71 72 /* 73 * Change a kernel page's homecache. It must not be mapped in user space. 74 * If !CONFIG_HOMECACHE, only usable on LOWMEM, and can only be called when 75 * no other cpu can reference the page, and causes a full-chip cache/TLB flush. 76 */ 77 extern void homecache_change_page_home(struct page *, int order, int home); 78 79 /* 80 * Flush a page out of whatever cache(s) it is in. 81 * This is more than just finv, since it properly handles waiting 82 * for the data to reach memory on tilepro, but it can be quite 83 * heavyweight, particularly on hash-for-home memory. 84 */ 85 extern void homecache_flush_cache(struct page *, int order); 86 87 /* 88 * Allocate a page with the given GFP flags, home, and optionally 89 * node. These routines are actually just wrappers around the normal 90 * alloc_pages() / alloc_pages_node() functions, which set and clear 91 * a per-cpu variable to communicate with homecache_new_kernel_page(). 92 * If !CONFIG_HOMECACHE, uses homecache_change_page_home(). 93 */ 94 extern struct page *homecache_alloc_pages(gfp_t gfp_mask, 95 unsigned int order, int home); 96 extern struct page *homecache_alloc_pages_node(int nid, gfp_t gfp_mask, 97 unsigned int order, int home); 98 #define homecache_alloc_page(gfp_mask, home) \ 99 homecache_alloc_pages(gfp_mask, 0, home) 100 101 /* 102 * These routines are just pass-throughs to free_pages() when 103 * we support full homecaching. If !CONFIG_HOMECACHE, then these 104 * routines use homecache_change_page_home() to reset the home 105 * back to the default before returning the page to the allocator. 106 */ 107 void homecache_free_pages(unsigned long addr, unsigned int order); 108 #define homecache_free_page(page) \ 109 homecache_free_pages((page), 0) 110 111 112 113 /* 114 * Report the page home for LOWMEM pages by examining their kernel PTE, 115 * or for highmem pages as the default home. 116 */ 117 extern int page_home(struct page *); 118 119 #define homecache_migrate_kthread() do {} while (0) 120 121 #define homecache_kpte_lock() 0 122 #define homecache_kpte_unlock(flags) do {} while (0) 123 124 125 #endif /* _ASM_TILE_HOMECACHE_H */ 126