Merge git://git.infradead.org/mtd-2.6
[linux-2.6] / arch / arm / plat-omap / fb.c
1 /*
2  * File: arch/arm/plat-omap/fb.c
3  *
4  * Framebuffer device registration for TI OMAP platforms
5  *
6  * Copyright (C) 2006 Nokia Corporation
7  * Author: Imre Deak <imre.deak@nokia.com>
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the
11  * Free Software Foundation; either version 2 of the License, or (at your
12  * option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write to the Free Software Foundation, Inc.,
21  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
22  */
23
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/mm.h>
27 #include <linux/init.h>
28 #include <linux/platform_device.h>
29 #include <linux/bootmem.h>
30
31 #include <asm/hardware.h>
32 #include <asm/io.h>
33 #include <asm/mach-types.h>
34 #include <asm/mach/map.h>
35
36 #include <asm/arch/board.h>
37 #include <asm/arch/sram.h>
38 #include <asm/arch/omapfb.h>
39
40 #if defined(CONFIG_FB_OMAP) || defined(CONFIG_FB_OMAP_MODULE)
41
42 static struct omapfb_platform_data omapfb_config;
43 static int config_invalid;
44 static int configured_regions;
45
46 static u64 omap_fb_dma_mask = ~(u32)0;
47
48 static struct platform_device omap_fb_device = {
49         .name           = "omapfb",
50         .id             = -1,
51         .dev = {
52                 .dma_mask               = &omap_fb_dma_mask,
53                 .coherent_dma_mask      = ~(u32)0,
54                 .platform_data          = &omapfb_config,
55         },
56         .num_resources = 0,
57 };
58
59 static inline int ranges_overlap(unsigned long start1, unsigned long size1,
60                                  unsigned long start2, unsigned long size2)
61 {
62         return (start1 >= start2 && start1 < start2 + size2) ||
63                (start2 >= start1 && start2 < start1 + size1);
64 }
65
66 static inline int range_included(unsigned long start1, unsigned long size1,
67                                  unsigned long start2, unsigned long size2)
68 {
69         return start1 >= start2 && start1 + size1 <= start2 + size2;
70 }
71
72
73 /* Check if there is an overlapping region. */
74 static int fbmem_region_reserved(unsigned long start, size_t size)
75 {
76         struct omapfb_mem_region *rg;
77         int i;
78
79         rg = &omapfb_config.mem_desc.region[0];
80         for (i = 0; i < OMAPFB_PLANE_NUM; i++, rg++) {
81                 if (!rg->paddr)
82                         /* Empty slot. */
83                         continue;
84                 if (ranges_overlap(start, size, rg->paddr, rg->size))
85                         return 1;
86         }
87         return 0;
88 }
89
90 /*
91  * Get the region_idx`th region from board config/ATAG and convert it to
92  * our internal format.
93  */
94 static int get_fbmem_region(int region_idx, struct omapfb_mem_region *rg)
95 {
96         const struct omap_fbmem_config  *conf;
97         u32                             paddr;
98
99         conf = omap_get_nr_config(OMAP_TAG_FBMEM,
100                                   struct omap_fbmem_config, region_idx);
101         if (conf == NULL)
102                 return -ENOENT;
103
104         paddr = conf->start;
105         /*
106          * Low bits encode the page allocation mode, if high bits
107          * are zero. Otherwise we need a page aligned fixed
108          * address.
109          */
110         memset(rg, 0, sizeof(*rg));
111         rg->type = paddr & ~PAGE_MASK;
112         rg->paddr = paddr & PAGE_MASK;
113         rg->size = PAGE_ALIGN(conf->size);
114         return 0;
115 }
116
117 static int set_fbmem_region_type(struct omapfb_mem_region *rg, int mem_type,
118                                   unsigned long mem_start,
119                                   unsigned long mem_size)
120 {
121         /*
122          * Check if the configuration specifies the type explicitly.
123          * type = 0 && paddr = 0, a default don't care case maps to
124          * the SDRAM type.
125          */
126         if (rg->type || (!rg->type && !rg->paddr))
127                 return 0;
128         if (ranges_overlap(rg->paddr, rg->size, mem_start, mem_size)) {
129                 rg->type = mem_type;
130                 return 0;
131         }
132         /* Can't determine it. */
133         return -1;
134 }
135
136 static int check_fbmem_region(int region_idx, struct omapfb_mem_region *rg,
137                               unsigned long start_avail, unsigned size_avail)
138 {
139         unsigned long   paddr = rg->paddr;
140         size_t          size = rg->size;
141
142         if (rg->type > OMAPFB_MEMTYPE_MAX) {
143                 printk(KERN_ERR
144                         "Invalid start address for FB region %d\n", region_idx);
145                 return -EINVAL;
146         }
147
148         if (!rg->size) {
149                 printk(KERN_ERR "Zero size for FB region %d\n", region_idx);
150                 return -EINVAL;
151         }
152
153         if (!paddr)
154                 /* Allocate this dynamically, leave paddr 0 for now. */
155                 return 0;
156
157         /*
158          * Fixed region for the given RAM range. Check if it's already
159          * reserved by the FB code or someone else.
160          */
161         if (fbmem_region_reserved(paddr, size) ||
162             !range_included(paddr, size, start_avail, size_avail)) {
163                 printk(KERN_ERR "Trying to use reserved memory "
164                         "for FB region %d\n", region_idx);
165                 return -EINVAL;
166         }
167
168         return 0;
169 }
170
171 /*
172  * Called from map_io. We need to call to this early enough so that we
173  * can reserve the fixed SDRAM regions before VM could get hold of them.
174  */
175 void __init omapfb_reserve_sdram(void)
176 {
177         struct bootmem_data     *bdata;
178         unsigned long           sdram_start, sdram_size;
179         unsigned long           reserved;
180         int                     i;
181
182         if (config_invalid)
183                 return;
184
185         bdata = NODE_DATA(0)->bdata;
186         sdram_start = bdata->node_min_pfn << PAGE_SHIFT;
187         sdram_size = (bdata->node_low_pfn << PAGE_SHIFT) - sdram_start;
188         reserved = 0;
189         for (i = 0; ; i++) {
190                 struct omapfb_mem_region        rg;
191
192                 if (get_fbmem_region(i, &rg) < 0)
193                         break;
194                 if (i == OMAPFB_PLANE_NUM) {
195                         printk(KERN_ERR
196                                 "Extraneous FB mem configuration entries\n");
197                         config_invalid = 1;
198                         return;
199                 }
200                 /* Check if it's our memory type. */
201                 if (set_fbmem_region_type(&rg, OMAPFB_MEMTYPE_SDRAM,
202                                           sdram_start, sdram_size) < 0 ||
203                     (rg.type != OMAPFB_MEMTYPE_SDRAM))
204                         continue;
205                 BUG_ON(omapfb_config.mem_desc.region[i].size);
206                 if (check_fbmem_region(i, &rg, sdram_start, sdram_size) < 0) {
207                         config_invalid = 1;
208                         return;
209                 }
210                 if (rg.paddr)
211                         reserve_bootmem(rg.paddr, rg.size, BOOTMEM_DEFAULT);
212                 reserved += rg.size;
213                 omapfb_config.mem_desc.region[i] = rg;
214                 configured_regions++;
215         }
216         omapfb_config.mem_desc.region_cnt = i;
217         if (reserved)
218                 pr_info("Reserving %lu bytes SDRAM for frame buffer\n",
219                          reserved);
220 }
221
222 /*
223  * Called at sram init time, before anything is pushed to the SRAM stack.
224  * Because of the stack scheme, we will allocate everything from the
225  * start of the lowest address region to the end of SRAM. This will also
226  * include padding for page alignment and possible holes between regions.
227  *
228  * As opposed to the SDRAM case, we'll also do any dynamic allocations at
229  * this point, since the driver built as a module would have problem with
230  * freeing / reallocating the regions.
231  */
232 unsigned long omapfb_reserve_sram(unsigned long sram_pstart,
233                                   unsigned long sram_vstart,
234                                   unsigned long sram_size,
235                                   unsigned long pstart_avail,
236                                   unsigned long size_avail)
237 {
238         struct omapfb_mem_region        rg;
239         unsigned long                   pend_avail;
240         unsigned long                   reserved;
241         int                             i;
242
243         if (config_invalid)
244                 return 0;
245
246         reserved = 0;
247         pend_avail = pstart_avail + size_avail;
248         for (i = 0; ; i++) {
249                 if (get_fbmem_region(i, &rg) < 0)
250                         break;
251                 if (i == OMAPFB_PLANE_NUM) {
252                         printk(KERN_ERR
253                                 "Extraneous FB mem configuration entries\n");
254                         config_invalid = 1;
255                         return 0;
256                 }
257
258                 /* Check if it's our memory type. */
259                 if (set_fbmem_region_type(&rg, OMAPFB_MEMTYPE_SRAM,
260                                           sram_pstart, sram_size) < 0 ||
261                     (rg.type != OMAPFB_MEMTYPE_SRAM))
262                         continue;
263                 BUG_ON(omapfb_config.mem_desc.region[i].size);
264
265                 if (check_fbmem_region(i, &rg, pstart_avail, size_avail) < 0) {
266                         config_invalid = 1;
267                         return 0;
268                 }
269
270                 if (!rg.paddr) {
271                         /* Dynamic allocation */
272                         if ((size_avail & PAGE_MASK) < rg.size) {
273                                 printk("Not enough SRAM for FB region %d\n",
274                                         i);
275                                 config_invalid = 1;
276                                 return 0;
277                         }
278                         size_avail = (size_avail - rg.size) & PAGE_MASK;
279                         rg.paddr = pstart_avail + size_avail;
280                 }
281                 /* Reserve everything above the start of the region. */
282                 if (pend_avail - rg.paddr > reserved)
283                         reserved = pend_avail - rg.paddr;
284                 size_avail = pend_avail - reserved - pstart_avail;
285
286                 /*
287                  * We have a kernel mapping for this already, so the
288                  * driver won't have to make one.
289                  */
290                 rg.vaddr = (void *)(sram_vstart + rg.paddr - sram_pstart);
291                 omapfb_config.mem_desc.region[i] = rg;
292                 configured_regions++;
293         }
294         omapfb_config.mem_desc.region_cnt = i;
295         if (reserved)
296                 pr_info("Reserving %lu bytes SRAM for frame buffer\n",
297                          reserved);
298         return reserved;
299 }
300
301 void omapfb_set_ctrl_platform_data(void *data)
302 {
303         omapfb_config.ctrl_platform_data = data;
304 }
305
306 static inline int omap_init_fb(void)
307 {
308         const struct omap_lcd_config *conf;
309
310         if (config_invalid)
311                 return 0;
312         if (configured_regions != omapfb_config.mem_desc.region_cnt) {
313                 printk(KERN_ERR "Invalid FB mem configuration entries\n");
314                 return 0;
315         }
316         conf = omap_get_config(OMAP_TAG_LCD, struct omap_lcd_config);
317         if (conf == NULL) {
318                 if (configured_regions)
319                         /* FB mem config, but no LCD config? */
320                         printk(KERN_ERR "Missing LCD configuration\n");
321                 return 0;
322         }
323         omapfb_config.lcd = *conf;
324
325         return platform_device_register(&omap_fb_device);
326 }
327
328 arch_initcall(omap_init_fb);
329
330 #else
331
332 void omapfb_reserve_sdram(void) {}
333 unsigned long omapfb_reserve_sram(unsigned long sram_pstart,
334                                   unsigned long sram_vstart,
335                                   unsigned long sram_size,
336                                   unsigned long start_avail,
337                                   unsigned long size_avail)
338 {
339         return 0;
340 }
341
342
343 #endif