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/init.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/bootmem.h>
  29
  30 #include <asm/hardware.h>
  31 #include <asm/io.h>
  32 #include <asm/mach-types.h>
  33 #include <asm/mach/map.h>
  34
  35 #include <asm/arch/board.h>
  36 #include <asm/arch/sram.h>
  37 #include <asm/arch/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 /* Get the region_idx`th region from board config/ATAG and convert it to
  90  * our internal format.
  91  */
  92 static int get_fbmem_region(int region_idx, struct omapfb_mem_region *rg)
  93 {
  94         const struct omap_fbmem_config  *conf;
  95         u32                             paddr;
  96
  97         conf = omap_get_nr_config(OMAP_TAG_FBMEM,
  98                                   struct omap_fbmem_config, region_idx);
  99         if (conf == NULL)
 100                 return -ENOENT;
 101
 102         paddr = conf->start;
 103         /* Low bits encode the page allocation mode, if high bits
 104          * are zero. Otherwise we need a page aligned fixed
 105          * address.
 106          */
 107         memset(rg, 0, sizeof(*rg));
 108         rg->type = paddr & ~PAGE_MASK;
 109         rg->paddr = paddr & PAGE_MASK;
 110         rg->size = PAGE_ALIGN(conf->size);
 111         return 0;
 112 }
 113
 114 static int set_fbmem_region_type(struct omapfb_mem_region *rg, int mem_type,
 115                                   unsigned long mem_start,
 116                                   unsigned long mem_size)
 117 {
 118         /* Check if the configuration specifies the type explicitly.
 119          * type = 0 && paddr = 0, a default don't care case maps to
 120          * the SDRAM type.
 121          */
 122         if (rg->type || (!rg->type && !rg->paddr))
 123                 return 0;
 124         if (ranges_overlap(rg->paddr, rg->size, mem_start, mem_size)) {
 125                 rg->type = mem_type;
 126                 return 0;
 127         }
 128         /* Can't determine it. */
 129         return -1;
 130 }
 131
 132 static int check_fbmem_region(int region_idx, struct omapfb_mem_region *rg,
 133                               unsigned long start_avail, unsigned size_avail)
 134 {
 135         unsigned long   paddr = rg->paddr;
 136         size_t          size = rg->size;
 137
 138         if (rg->type > OMAPFB_MEMTYPE_MAX) {
 139                 printk(KERN_ERR
 140                         "Invalid start address for FB region %d\n", region_idx);
 141                 return -EINVAL;
 142         }
 143
 144         if (!rg->size) {
 145                 printk(KERN_ERR "Zero size for FB region %d\n", region_idx);
 146                 return -EINVAL;
 147         }
 148
 149         if (!paddr)
 150                 /* Allocate this dynamically, leave paddr 0 for now. */
 151                 return 0;
 152
 153         /* Fixed region for the given RAM range. Check if it's already
 154          * reserved by the FB code or someone else.
 155          */
 156         if (fbmem_region_reserved(paddr, size) ||
 157             !range_included(paddr, size, start_avail, size_avail)) {
 158                 printk(KERN_ERR "Trying to use reserved memory "
 159                         "for FB region %d\n", region_idx);
 160                 return -EINVAL;
 161         }
 162
 163         return 0;
 164 }
 165
 166 /* Called from map_io. We need to call to this early enough so that we
 167  * can reserve the fixed SDRAM regions before VM could get hold of them.
 168  */
 169 void omapfb_reserve_sdram(void)
 170 {
 171         struct bootmem_data     *bdata;
 172         unsigned long           sdram_start, sdram_size;
 173         unsigned long           reserved;
 174         int                     i;
 175
 176         if (config_invalid)
 177                 return;
 178
 179         bdata = NODE_DATA(0)->bdata;
 180         sdram_start = bdata->node_boot_start;
 181         sdram_size = (bdata->node_low_pfn << PAGE_SHIFT) - sdram_start;
 182         reserved = 0;
 183         for (i = 0; ; i++) {
 184                 struct omapfb_mem_region        rg;
 185
 186                 if (get_fbmem_region(i, &rg) < 0)
 187                         break;
 188                 if (i == OMAPFB_PLANE_NUM) {
 189                         printk(KERN_ERR
 190                                 "Extraneous FB mem configuration entries\n");
 191                         config_invalid = 1;
 192                         return;
 193                 }
 194                 /* Check if it's our memory type. */
 195                 if (set_fbmem_region_type(&rg, OMAPFB_MEMTYPE_SDRAM,
 196                                           sdram_start, sdram_size) < 0 ||
 197                     (rg.type != OMAPFB_MEMTYPE_SDRAM))
 198                         continue;
 199                 BUG_ON(omapfb_config.mem_desc.region[i].size);
 200                 if (check_fbmem_region(i, &rg, sdram_start, sdram_size) < 0) {
 201                         config_invalid = 1;
 202                         return;
 203                 }
 204                 if (rg.paddr)
 205                         reserve_bootmem(rg.paddr, rg.size);
 206                 reserved += rg.size;
 207                 omapfb_config.mem_desc.region[i] = rg;
 208                 configured_regions++;
 209         }
 210         omapfb_config.mem_desc.region_cnt = i;
 211         if (reserved)
 212                 pr_info("Reserving %lu bytes SDRAM for frame buffer\n",
 213                          reserved);
 214 }
 215
 216 /* Called at sram init time, before anything is pushed to the SRAM stack.
 217  * Because of the stack scheme, we will allocate everything from the
 218  * start of the lowest address region to the end of SRAM. This will also
 219  * include padding for page alignment and possible holes between regions.
 220  *
 221  * As opposed to the SDRAM case, we'll also do any dynamic allocations at
 222  * this point, since the driver built as a module would have problem with
 223  * freeing / reallocating the regions.
 224  */
 225 unsigned long omapfb_reserve_sram(unsigned long sram_pstart,
 226                                   unsigned long sram_vstart,
 227                                   unsigned long sram_size,
 228                                   unsigned long pstart_avail,
 229                                   unsigned long size_avail)
 230 {
 231         struct omapfb_mem_region        rg;
 232         unsigned long                   pend_avail;
 233         unsigned long                   reserved;
 234         int                             i;
 235
 236         if (config_invalid)
 237                 return 0;
 238
 239         reserved = 0;
 240         pend_avail = pstart_avail + size_avail;
 241         for (i = 0; ; i++) {
 242                 if (get_fbmem_region(i, &rg) < 0)
 243                         break;
 244                 if (i == OMAPFB_PLANE_NUM) {
 245                         printk(KERN_ERR
 246                                 "Extraneous FB mem configuration entries\n");
 247                         config_invalid = 1;
 248                         return 0;
 249                 }
 250
 251                 /* Check if it's our memory type. */
 252                 if (set_fbmem_region_type(&rg, OMAPFB_MEMTYPE_SRAM,
 253                                           sram_pstart, sram_size) < 0 ||
 254                     (rg.type != OMAPFB_MEMTYPE_SRAM))
 255                         continue;
 256                 BUG_ON(omapfb_config.mem_desc.region[i].size);
 257
 258                 if (check_fbmem_region(i, &rg, pstart_avail, size_avail) < 0) {
 259                         config_invalid = 1;
 260                         return 0;
 261                 }
 262
 263                 if (!rg.paddr) {
 264                         /* Dynamic allocation */
 265                         if ((size_avail & PAGE_MASK) < rg.size) {
 266                                 printk("Not enough SRAM for FB region %d\n",
 267                                         i);
 268                                 config_invalid = 1;
 269                                 return 0;
 270                         }
 271                         size_avail = (size_avail - rg.size) & PAGE_MASK;
 272                         rg.paddr = pstart_avail + size_avail;
 273                 }
 274                 /* Reserve everything above the start of the region.
 275                  */
 276                 if (pend_avail - rg.paddr > reserved)
 277                         reserved = pend_avail - rg.paddr;
 278                 size_avail = pend_avail - reserved - pstart_avail;
 279
 280                 /* We have a kernel mapping for this already, so the
 281                  * driver won't have to make one.
 282                  */
 283                 rg.vaddr = (void *)(sram_vstart + rg.paddr - sram_pstart);
 284                 omapfb_config.mem_desc.region[i] = rg;
 285                 configured_regions++;
 286         }
 287         omapfb_config.mem_desc.region_cnt = i;
 288         if (reserved)
 289                 pr_info("Reserving %lu bytes SRAM for frame buffer\n",
 290                          reserved);
 291         return reserved;
 292 }
 293
 294 void omapfb_set_ctrl_platform_data(void *data)
 295 {
 296         omapfb_config.ctrl_platform_data = data;
 297 }
 298
 299 static inline int omap_init_fb(void)
 300 {
 301         const struct omap_lcd_config *conf;
 302
 303         if (config_invalid)
 304                 return 0;
 305         if (configured_regions != omapfb_config.mem_desc.region_cnt) {
 306                 printk(KERN_ERR "Invalid FB mem configuration entries\n");
 307                 return 0;
 308         }
 309         conf = omap_get_config(OMAP_TAG_LCD, struct omap_lcd_config);
 310         if (conf == NULL) {
 311                 if (configured_regions)
 312                         /* FB mem config, but no LCD config? */
 313                         printk(KERN_ERR "Missing LCD configuration\n");
 314                 return 0;
 315         }
 316         omapfb_config.lcd = *conf;
 317
 318         return platform_device_register(&omap_fb_device);
 319 }
 320
 321 arch_initcall(omap_init_fb);
 322
 323 #else
 324
 325 void omapfb_reserve_sdram(void) {}
 326 unsigned long omapfb_reserve_sram(unsigned long sram_pstart,
 327                                   unsigned long sram_vstart,
 328                                   unsigned long sram_size,
 329                                   unsigned long start_avail,
 330                                   unsigned long size_avail) {}
 331
 332
 333 #endif
 334
 335