| 1 | /* $NetBSD: drm_cache.c,v 1.8 2015/10/17 21:11:56 jmcneill Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2013 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Taylor R. Campbell. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | #include <sys/cdefs.h> |
| 33 | __KERNEL_RCSID(0, "$NetBSD: drm_cache.c,v 1.8 2015/10/17 21:11:56 jmcneill Exp $" ); |
| 34 | |
| 35 | #include <sys/param.h> |
| 36 | #include <sys/types.h> |
| 37 | #include <sys/xcall.h> |
| 38 | |
| 39 | #include <uvm/uvm_extern.h> |
| 40 | |
| 41 | #include <linux/mm_types.h> |
| 42 | |
| 43 | #include <drm/drmP.h> |
| 44 | |
| 45 | #if !defined(__arm__) |
| 46 | #define DRM_CLFLUSH 1 |
| 47 | #endif |
| 48 | |
| 49 | #if defined(DRM_CLFLUSH) |
| 50 | static bool drm_md_clflush_finegrained_p(void); |
| 51 | static void drm_md_clflush_all(void); |
| 52 | static void drm_md_clflush_page(struct page *); |
| 53 | static void drm_md_clflush_virt_range(const void *, size_t); |
| 54 | #endif |
| 55 | |
| 56 | void |
| 57 | drm_clflush_pages(struct page **pages, unsigned long npages) |
| 58 | { |
| 59 | #if defined(DRM_CLFLUSH) |
| 60 | if (drm_md_clflush_finegrained_p()) { |
| 61 | while (npages--) |
| 62 | drm_md_clflush_page(pages[npages]); |
| 63 | } else { |
| 64 | drm_md_clflush_all(); |
| 65 | } |
| 66 | #endif |
| 67 | } |
| 68 | |
| 69 | void |
| 70 | drm_clflush_pglist(struct pglist *list) |
| 71 | { |
| 72 | #if defined(DRM_CLFLUSH) |
| 73 | if (drm_md_clflush_finegrained_p()) { |
| 74 | struct vm_page *page; |
| 75 | |
| 76 | TAILQ_FOREACH(page, list, pageq.queue) |
| 77 | drm_md_clflush_page(container_of(page, struct page, |
| 78 | p_vmp)); |
| 79 | } else { |
| 80 | drm_md_clflush_all(); |
| 81 | } |
| 82 | #endif |
| 83 | } |
| 84 | |
| 85 | void |
| 86 | drm_clflush_page(struct page *page) |
| 87 | { |
| 88 | #if defined(DRM_CLFLUSH) |
| 89 | if (drm_md_clflush_finegrained_p()) |
| 90 | drm_md_clflush_page(page); |
| 91 | else |
| 92 | drm_md_clflush_all(); |
| 93 | #endif |
| 94 | } |
| 95 | |
| 96 | void |
| 97 | drm_clflush_virt_range(const void *vaddr, size_t nbytes) |
| 98 | { |
| 99 | #if defined(DRM_CLFLUSH) |
| 100 | if (drm_md_clflush_finegrained_p()) |
| 101 | drm_md_clflush_virt_range(vaddr, nbytes); |
| 102 | else |
| 103 | drm_md_clflush_all(); |
| 104 | #endif |
| 105 | } |
| 106 | |
| 107 | #if defined(__i386__) || defined(__x86_64__) |
| 108 | |
| 109 | #include <machine/cpufunc.h> |
| 110 | |
| 111 | static bool |
| 112 | drm_md_clflush_finegrained_p(void) |
| 113 | { |
| 114 | return ISSET(cpu_info_primary.ci_feat_val[0], CPUID_CFLUSH); |
| 115 | } |
| 116 | |
| 117 | static void |
| 118 | drm_x86_clflush(const void *vaddr) |
| 119 | { |
| 120 | asm volatile ("clflush %0" : : "m" (*(const char *)vaddr)); |
| 121 | } |
| 122 | |
| 123 | static size_t |
| 124 | drm_x86_clflush_size(void) |
| 125 | { |
| 126 | KASSERT(drm_md_clflush_finegrained_p()); |
| 127 | return cpu_info_primary.ci_cflush_lsize; |
| 128 | } |
| 129 | |
| 130 | static void |
| 131 | drm_x86_clflush_xc(void *arg0 __unused, void *arg1 __unused) |
| 132 | { |
| 133 | wbinvd(); |
| 134 | } |
| 135 | |
| 136 | static void |
| 137 | drm_md_clflush_all(void) |
| 138 | { |
| 139 | xc_wait(xc_broadcast(0, &drm_x86_clflush_xc, NULL, NULL)); |
| 140 | } |
| 141 | |
| 142 | static void |
| 143 | drm_md_clflush_page(struct page *page) |
| 144 | { |
| 145 | void *const vaddr = kmap_atomic(page); |
| 146 | |
| 147 | drm_md_clflush_virt_range(vaddr, PAGE_SIZE); |
| 148 | |
| 149 | kunmap_atomic(vaddr); |
| 150 | } |
| 151 | |
| 152 | static void |
| 153 | drm_md_clflush_virt_range(const void *vaddr, size_t nbytes) |
| 154 | { |
| 155 | const unsigned clflush_size = drm_x86_clflush_size(); |
| 156 | const vaddr_t va = (vaddr_t)vaddr; |
| 157 | const char *const start = (const void *)rounddown(va, clflush_size); |
| 158 | const char *const end = (const void *)roundup(va + nbytes, |
| 159 | clflush_size); |
| 160 | const char *p; |
| 161 | |
| 162 | /* Support for CLFLUSH implies support for MFENCE. */ |
| 163 | KASSERT(drm_md_clflush_finegrained_p()); |
| 164 | x86_mfence(); |
| 165 | for (p = start; p < end; p += clflush_size) |
| 166 | drm_x86_clflush(p); |
| 167 | x86_mfence(); |
| 168 | } |
| 169 | |
| 170 | #endif /* defined(__i386__) || defined(__x86_64__) */ |
| 171 | |