drm: use NULL instead of 0
[linux-2.6] / drivers / char / drm / ati_pcigart.c
1 /**
2  * \file ati_pcigart.c
3  * ATI PCI GART support
4  *
5  * \author Gareth Hughes <gareth@valinux.com>
6  */
7
8 /*
9  * Created: Wed Dec 13 21:52:19 2000 by gareth@valinux.com
10  *
11  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
12  * All Rights Reserved.
13  *
14  * Permission is hereby granted, free of charge, to any person obtaining a
15  * copy of this software and associated documentation files (the "Software"),
16  * to deal in the Software without restriction, including without limitation
17  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
18  * and/or sell copies of the Software, and to permit persons to whom the
19  * Software is furnished to do so, subject to the following conditions:
20  *
21  * The above copyright notice and this permission notice (including the next
22  * paragraph) shall be included in all copies or substantial portions of the
23  * Software.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
26  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
28  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
29  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
30  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
31  * DEALINGS IN THE SOFTWARE.
32  */
33
34 #include "drmP.h"
35
36 #if PAGE_SIZE == 65536
37 # define ATI_PCIGART_TABLE_ORDER        0
38 # define ATI_PCIGART_TABLE_PAGES        (1 << 0)
39 #elif PAGE_SIZE == 16384
40 # define ATI_PCIGART_TABLE_ORDER        1
41 # define ATI_PCIGART_TABLE_PAGES        (1 << 1)
42 #elif PAGE_SIZE == 8192
43 # define ATI_PCIGART_TABLE_ORDER        2
44 # define ATI_PCIGART_TABLE_PAGES        (1 << 2)
45 #elif PAGE_SIZE == 4096
46 # define ATI_PCIGART_TABLE_ORDER        3
47 # define ATI_PCIGART_TABLE_PAGES        (1 << 3)
48 #else
49 # error - PAGE_SIZE not 64K, 16K, 8K or 4K
50 #endif
51
52 # define ATI_MAX_PCIGART_PAGES          8192    /**< 32 MB aperture, 4K pages */
53 # define ATI_PCIGART_PAGE_SIZE          4096    /**< PCI GART page size */
54
55 static void *drm_ati_alloc_pcigart_table(void)
56 {
57         unsigned long address;
58         struct page *page;
59         int i;
60         DRM_DEBUG("%s\n", __FUNCTION__);
61
62         address = __get_free_pages(GFP_KERNEL, ATI_PCIGART_TABLE_ORDER);
63         if (address == 0UL) {
64                 return NULL;
65         }
66
67         page = virt_to_page(address);
68
69         for (i = 0; i < ATI_PCIGART_TABLE_PAGES; i++, page++) {
70                 get_page(page);
71                 SetPageReserved(page);
72         }
73
74         DRM_DEBUG("%s: returning 0x%08lx\n", __FUNCTION__, address);
75         return (void *)address;
76 }
77
78 static void drm_ati_free_pcigart_table(void *address)
79 {
80         struct page *page;
81         int i;
82         DRM_DEBUG("%s\n", __FUNCTION__);
83
84         page = virt_to_page((unsigned long)address);
85
86         for (i = 0; i < ATI_PCIGART_TABLE_PAGES; i++, page++) {
87                 __put_page(page);
88                 ClearPageReserved(page);
89         }
90
91         free_pages((unsigned long)address, ATI_PCIGART_TABLE_ORDER);
92 }
93
94 int drm_ati_pcigart_cleanup(drm_device_t *dev, drm_ati_pcigart_info *gart_info)
95 {
96         drm_sg_mem_t *entry = dev->sg;
97         unsigned long pages;
98         int i;
99
100         /* we need to support large memory configurations */
101         if (!entry) {
102                 DRM_ERROR("no scatter/gather memory!\n");
103                 return 0;
104         }
105
106         if (gart_info->bus_addr) {
107                 if (gart_info->gart_table_location == DRM_ATI_GART_MAIN) {
108                         pci_unmap_single(dev->pdev, gart_info->bus_addr,
109                                          ATI_PCIGART_TABLE_PAGES * PAGE_SIZE,
110                                          PCI_DMA_TODEVICE);
111                 }
112
113                 pages = (entry->pages <= ATI_MAX_PCIGART_PAGES)
114                     ? entry->pages : ATI_MAX_PCIGART_PAGES;
115
116                 for (i = 0; i < pages; i++) {
117                         if (!entry->busaddr[i])
118                                 break;
119                         pci_unmap_single(dev->pdev, entry->busaddr[i],
120                                          PAGE_SIZE, PCI_DMA_TODEVICE);
121                 }
122
123                 if (gart_info->gart_table_location == DRM_ATI_GART_MAIN)
124                         gart_info->bus_addr = 0;
125         }
126
127         if (gart_info->gart_table_location == DRM_ATI_GART_MAIN
128             && gart_info->addr) {
129                 drm_ati_free_pcigart_table(gart_info->addr);
130                 gart_info->addr = NULL;
131         }
132
133         return 1;
134 }
135
136 EXPORT_SYMBOL(drm_ati_pcigart_cleanup);
137
138 int drm_ati_pcigart_init(drm_device_t *dev, drm_ati_pcigart_info *gart_info)
139 {
140         drm_sg_mem_t *entry = dev->sg;
141         void *address = NULL;
142         unsigned long pages;
143         u32 *pci_gart, page_base, bus_address = 0;
144         int i, j, ret = 0;
145
146         if (!entry) {
147                 DRM_ERROR("no scatter/gather memory!\n");
148                 goto done;
149         }
150
151         if (gart_info->gart_table_location == DRM_ATI_GART_MAIN) {
152                 DRM_DEBUG("PCI: no table in VRAM: using normal RAM\n");
153
154                 address = drm_ati_alloc_pcigart_table();
155                 if (!address) {
156                         DRM_ERROR("cannot allocate PCI GART page!\n");
157                         goto done;
158                 }
159
160                 if (!dev->pdev) {
161                         DRM_ERROR("PCI device unknown!\n");
162                         goto done;
163                 }
164
165                 bus_address = pci_map_single(dev->pdev, address,
166                                              ATI_PCIGART_TABLE_PAGES *
167                                              PAGE_SIZE, PCI_DMA_TODEVICE);
168                 if (bus_address == 0) {
169                         DRM_ERROR("unable to map PCIGART pages!\n");
170                         drm_ati_free_pcigart_table(address);
171                         address = NULL;
172                         goto done;
173                 }
174         } else {
175                 address = gart_info->addr;
176                 bus_address = gart_info->bus_addr;
177                 DRM_DEBUG("PCI: Gart Table: VRAM %08X mapped at %08lX\n",
178                           bus_address, (unsigned long)address);
179         }
180
181         pci_gart = (u32 *) address;
182
183         pages = (entry->pages <= ATI_MAX_PCIGART_PAGES)
184             ? entry->pages : ATI_MAX_PCIGART_PAGES;
185
186         memset(pci_gart, 0, ATI_MAX_PCIGART_PAGES * sizeof(u32));
187
188         for (i = 0; i < pages; i++) {
189                 /* we need to support large memory configurations */
190                 entry->busaddr[i] = pci_map_single(dev->pdev,
191                                                    page_address(entry->
192                                                                 pagelist[i]),
193                                                    PAGE_SIZE, PCI_DMA_TODEVICE);
194                 if (entry->busaddr[i] == 0) {
195                         DRM_ERROR("unable to map PCIGART pages!\n");
196                         drm_ati_pcigart_cleanup(dev, gart_info);
197                         address = NULL;
198                         bus_address = 0;
199                         goto done;
200                 }
201                 page_base = (u32) entry->busaddr[i];
202
203                 for (j = 0; j < (PAGE_SIZE / ATI_PCIGART_PAGE_SIZE); j++) {
204                         if (gart_info->is_pcie)
205                                 *pci_gart = cpu_to_le32((page_base >> 8) | 0xc);
206                         else
207                                 *pci_gart = cpu_to_le32(page_base);
208                         pci_gart++;
209                         page_base += ATI_PCIGART_PAGE_SIZE;
210                 }
211         }
212
213         ret = 1;
214
215 #if defined(__i386__) || defined(__x86_64__)
216         wbinvd();
217 #else
218         mb();
219 #endif
220
221       done:
222         gart_info->addr = address;
223         gart_info->bus_addr = bus_address;
224         return ret;
225 }
226
227 EXPORT_SYMBOL(drm_ati_pcigart_init);