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)
50static bool drm_md_clflush_finegrained_p(void);
51static void drm_md_clflush_all(void);
52static void drm_md_clflush_page(struct page *);
53static void drm_md_clflush_virt_range(const void *, size_t);
54#endif
55
56void
57drm_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
69void
70drm_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
85void
86drm_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
96void
97drm_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
111static bool
112drm_md_clflush_finegrained_p(void)
113{
114 return ISSET(cpu_info_primary.ci_feat_val[0], CPUID_CFLUSH);
115}
116
117static void
118drm_x86_clflush(const void *vaddr)
119{
120 asm volatile ("clflush %0" : : "m" (*(const char *)vaddr));
121}
122
123static size_t
124drm_x86_clflush_size(void)
125{
126 KASSERT(drm_md_clflush_finegrained_p());
127 return cpu_info_primary.ci_cflush_lsize;
128}
129
130static void
131drm_x86_clflush_xc(void *arg0 __unused, void *arg1 __unused)
132{
133 wbinvd();
134}
135
136static void
137drm_md_clflush_all(void)
138{
139 xc_wait(xc_broadcast(0, &drm_x86_clflush_xc, NULL, NULL));
140}
141
142static void
143drm_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
152static void
153drm_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