| Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 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 */ |