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