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