arch/arm/mach-omap2/gpmc.c

   1 /*
   2  * GPMC support functions
   3  *
   4  * Copyright (C) 2005-2006 Nokia Corporation
   5  *
   6  * Author: Juha Yrjola
   7  *
   8  * Copyright (C) 2009 Texas Instruments
   9  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15 #undef DEBUG
  16
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/err.h>
  20 #include <linux/clk.h>
  21 #include <linux/ioport.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/io.h>
  24 #include <linux/module.h>
  25
  26 #include <asm/mach-types.h>
  27 #include <mach/gpmc.h>
  28
  29 #include <mach/sdrc.h>
  30
  31 /* GPMC register offsets */
  32 #define GPMC_REVISION           0x00
  33 #define GPMC_SYSCONFIG          0x10
  34 #define GPMC_SYSSTATUS          0x14
  35 #define GPMC_IRQSTATUS          0x18
  36 #define GPMC_IRQENABLE          0x1c
  37 #define GPMC_TIMEOUT_CONTROL    0x40
  38 #define GPMC_ERR_ADDRESS        0x44
  39 #define GPMC_ERR_TYPE           0x48
  40 #define GPMC_CONFIG             0x50
  41 #define GPMC_STATUS             0x54
  42 #define GPMC_PREFETCH_CONFIG1   0x1e0
  43 #define GPMC_PREFETCH_CONFIG2   0x1e4
  44 #define GPMC_PREFETCH_CONTROL   0x1ec
  45 #define GPMC_PREFETCH_STATUS    0x1f0
  46 #define GPMC_ECC_CONFIG         0x1f4
  47 #define GPMC_ECC_CONTROL        0x1f8
  48 #define GPMC_ECC_SIZE_CONFIG    0x1fc
  49
  50 #define GPMC_CS0                0x60
  51 #define GPMC_CS_SIZE            0x30
  52
  53 #define GPMC_MEM_START          0x00000000
  54 #define GPMC_MEM_END            0x3FFFFFFF
  55 #define BOOT_ROM_SPACE          0x100000        /* 1MB */
  56
  57 #define GPMC_CHUNK_SHIFT        24              /* 16 MB */
  58 #define GPMC_SECTION_SHIFT      28              /* 128 MB */
  59
  60 #define PREFETCH_FIFOTHRESHOLD  (0x40 << 8)
  61 #define CS_NUM_SHIFT            24
  62 #define ENABLE_PREFETCH         (0x1 << 7)
  63 #define DMA_MPU_MODE            2
  64
  65 static struct resource  gpmc_mem_root;
  66 static struct resource  gpmc_cs_mem[GPMC_CS_NUM];
  67 static DEFINE_SPINLOCK(gpmc_mem_lock);
  68 static unsigned         gpmc_cs_map;
  69
  70 static void __iomem *gpmc_base;
  71
  72 static struct clk *gpmc_l3_clk;
  73
  74 static void gpmc_write_reg(int idx, u32 val)
  75 {
  76         __raw_writel(val, gpmc_base + idx);
  77 }
  78
  79 static u32 gpmc_read_reg(int idx)
  80 {
  81         return __raw_readl(gpmc_base + idx);
  82 }
  83
  84 void gpmc_cs_write_reg(int cs, int idx, u32 val)
  85 {
  86         void __iomem *reg_addr;
  87
  88         reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
  89         __raw_writel(val, reg_addr);
  90 }
  91
  92 u32 gpmc_cs_read_reg(int cs, int idx)
  93 {
  94         void __iomem *reg_addr;
  95
  96         reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
  97         return __raw_readl(reg_addr);
  98 }
  99
 100 /* TODO: Add support for gpmc_fck to clock framework and use it */
 101 unsigned long gpmc_get_fclk_period(void)
 102 {
 103         unsigned long rate = clk_get_rate(gpmc_l3_clk);
 104
 105         if (rate == 0) {
 106                 printk(KERN_WARNING "gpmc_l3_clk not enabled\n");
 107                 return 0;
 108         }
 109
 110         rate /= 1000;
 111         rate = 1000000000 / rate;       /* In picoseconds */
 112
 113         return rate;
 114 }
 115
 116 unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
 117 {
 118         unsigned long tick_ps;
 119
 120         /* Calculate in picosecs to yield more exact results */
 121         tick_ps = gpmc_get_fclk_period();
 122
 123         return (time_ns * 1000 + tick_ps - 1) / tick_ps;
 124 }
 125
 126 unsigned int gpmc_ticks_to_ns(unsigned int ticks)
 127 {
 128         return ticks * gpmc_get_fclk_period() / 1000;
 129 }
 130
 131 unsigned int gpmc_round_ns_to_ticks(unsigned int time_ns)
 132 {
 133         unsigned long ticks = gpmc_ns_to_ticks(time_ns);
 134
 135         return ticks * gpmc_get_fclk_period() / 1000;
 136 }
 137
 138 #ifdef DEBUG
 139 static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
 140                                int time, const char *name)
 141 #else
 142 static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
 143                                int time)
 144 #endif
 145 {
 146         u32 l;
 147         int ticks, mask, nr_bits;
 148
 149         if (time == 0)
 150                 ticks = 0;
 151         else
 152                 ticks = gpmc_ns_to_ticks(time);
 153         nr_bits = end_bit - st_bit + 1;
 154         if (ticks >= 1 << nr_bits) {
 155 #ifdef DEBUG
 156                 printk(KERN_INFO "GPMC CS%d: %-10s* %3d ns, %3d ticks >= %d\n",
 157                                 cs, name, time, ticks, 1 << nr_bits);
 158 #endif
 159                 return -1;
 160         }
 161
 162         mask = (1 << nr_bits) - 1;
 163         l = gpmc_cs_read_reg(cs, reg);
 164 #ifdef DEBUG
 165         printk(KERN_INFO
 166                 "GPMC CS%d: %-10s: %3d ticks, %3lu ns (was %3i ticks) %3d ns\n",
 167                cs, name, ticks, gpmc_get_fclk_period() * ticks / 1000,
 168                         (l >> st_bit) & mask, time);
 169 #endif
 170         l &= ~(mask << st_bit);
 171         l |= ticks << st_bit;
 172         gpmc_cs_write_reg(cs, reg, l);
 173
 174         return 0;
 175 }
 176
 177 #ifdef DEBUG
 178 #define GPMC_SET_ONE(reg, st, end, field) \
 179         if (set_gpmc_timing_reg(cs, (reg), (st), (end),         \
 180                         t->field, #field) < 0)                  \
 181                 return -1
 182 #else
 183 #define GPMC_SET_ONE(reg, st, end, field) \
 184         if (set_gpmc_timing_reg(cs, (reg), (st), (end), t->field) < 0) \
 185                 return -1
 186 #endif
 187
 188 int gpmc_cs_calc_divider(int cs, unsigned int sync_clk)
 189 {
 190         int div;
 191         u32 l;
 192
 193         l = sync_clk * 1000 + (gpmc_get_fclk_period() - 1);
 194         div = l / gpmc_get_fclk_period();
 195         if (div > 4)
 196                 return -1;
 197         if (div <= 0)
 198                 div = 1;
 199
 200         return div;
 201 }
 202
 203 int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
 204 {
 205         int div;
 206         u32 l;
 207
 208         div = gpmc_cs_calc_divider(cs, t->sync_clk);
 209         if (div < 0)
 210                 return -1;
 211
 212         GPMC_SET_ONE(GPMC_CS_CONFIG2,  0,  3, cs_on);
 213         GPMC_SET_ONE(GPMC_CS_CONFIG2,  8, 12, cs_rd_off);
 214         GPMC_SET_ONE(GPMC_CS_CONFIG2, 16, 20, cs_wr_off);
 215
 216         GPMC_SET_ONE(GPMC_CS_CONFIG3,  0,  3, adv_on);
 217         GPMC_SET_ONE(GPMC_CS_CONFIG3,  8, 12, adv_rd_off);
 218         GPMC_SET_ONE(GPMC_CS_CONFIG3, 16, 20, adv_wr_off);
 219
 220         GPMC_SET_ONE(GPMC_CS_CONFIG4,  0,  3, oe_on);
 221         GPMC_SET_ONE(GPMC_CS_CONFIG4,  8, 12, oe_off);
 222         GPMC_SET_ONE(GPMC_CS_CONFIG4, 16, 19, we_on);
 223         GPMC_SET_ONE(GPMC_CS_CONFIG4, 24, 28, we_off);
 224
 225         GPMC_SET_ONE(GPMC_CS_CONFIG5,  0,  4, rd_cycle);
 226         GPMC_SET_ONE(GPMC_CS_CONFIG5,  8, 12, wr_cycle);
 227         GPMC_SET_ONE(GPMC_CS_CONFIG5, 16, 20, access);
 228
 229         GPMC_SET_ONE(GPMC_CS_CONFIG5, 24, 27, page_burst_access);
 230
 231         if (cpu_is_omap34xx()) {
 232                 GPMC_SET_ONE(GPMC_CS_CONFIG6, 16, 19, wr_data_mux_bus);
 233                 GPMC_SET_ONE(GPMC_CS_CONFIG6, 24, 28, wr_access);
 234         }
 235
 236         /* caller is expected to have initialized CONFIG1 to cover
 237          * at least sync vs async
 238          */
 239         l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
 240         if (l & (GPMC_CONFIG1_READTYPE_SYNC | GPMC_CONFIG1_WRITETYPE_SYNC)) {
 241 #ifdef DEBUG
 242                 printk(KERN_INFO "GPMC CS%d CLK period is %lu ns (div %d)\n",
 243                                 cs, (div * gpmc_get_fclk_period()) / 1000, div);
 244 #endif
 245                 l &= ~0x03;
 246                 l |= (div - 1);
 247                 gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
 248         }
 249
 250         return 0;
 251 }
 252
 253 static void gpmc_cs_enable_mem(int cs, u32 base, u32 size)
 254 {
 255         u32 l;
 256         u32 mask;
 257
 258         mask = (1 << GPMC_SECTION_SHIFT) - size;
 259         l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
 260         l &= ~0x3f;
 261         l = (base >> GPMC_CHUNK_SHIFT) & 0x3f;
 262         l &= ~(0x0f << 8);
 263         l |= ((mask >> GPMC_CHUNK_SHIFT) & 0x0f) << 8;
 264         l |= 1 << 6;            /* CSVALID */
 265         gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
 266 }
 267
 268 static void gpmc_cs_disable_mem(int cs)
 269 {
 270         u32 l;
 271
 272         l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
 273         l &= ~(1 << 6);         /* CSVALID */
 274         gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
 275 }
 276
 277 static void gpmc_cs_get_memconf(int cs, u32 *base, u32 *size)
 278 {
 279         u32 l;
 280         u32 mask;
 281
 282         l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
 283         *base = (l & 0x3f) << GPMC_CHUNK_SHIFT;
 284         mask = (l >> 8) & 0x0f;
 285         *size = (1 << GPMC_SECTION_SHIFT) - (mask << GPMC_CHUNK_SHIFT);
 286 }
 287
 288 static int gpmc_cs_mem_enabled(int cs)
 289 {
 290         u32 l;
 291
 292         l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
 293         return l & (1 << 6);
 294 }
 295
 296 int gpmc_cs_set_reserved(int cs, int reserved)
 297 {
 298         if (cs > GPMC_CS_NUM)
 299                 return -ENODEV;
 300
 301         gpmc_cs_map &= ~(1 << cs);
 302         gpmc_cs_map |= (reserved ? 1 : 0) << cs;
 303
 304         return 0;
 305 }
 306
 307 int gpmc_cs_reserved(int cs)
 308 {
 309         if (cs > GPMC_CS_NUM)
 310                 return -ENODEV;
 311
 312         return gpmc_cs_map & (1 << cs);
 313 }
 314
 315 static unsigned long gpmc_mem_align(unsigned long size)
 316 {
 317         int order;
 318
 319         size = (size - 1) >> (GPMC_CHUNK_SHIFT - 1);
 320         order = GPMC_CHUNK_SHIFT - 1;
 321         do {
 322                 size >>= 1;
 323                 order++;
 324         } while (size);
 325         size = 1 << order;
 326         return size;
 327 }
 328
 329 static int gpmc_cs_insert_mem(int cs, unsigned long base, unsigned long size)
 330 {
 331         struct resource *res = &gpmc_cs_mem[cs];
 332         int r;
 333
 334         size = gpmc_mem_align(size);
 335         spin_lock(&gpmc_mem_lock);
 336         res->start = base;
 337         res->end = base + size - 1;
 338         r = request_resource(&gpmc_mem_root, res);
 339         spin_unlock(&gpmc_mem_lock);
 340
 341         return r;
 342 }
 343
 344 int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
 345 {
 346         struct resource *res = &gpmc_cs_mem[cs];
 347         int r = -1;
 348
 349         if (cs > GPMC_CS_NUM)
 350                 return -ENODEV;
 351
 352         size = gpmc_mem_align(size);
 353         if (size > (1 << GPMC_SECTION_SHIFT))
 354                 return -ENOMEM;
 355
 356         spin_lock(&gpmc_mem_lock);
 357         if (gpmc_cs_reserved(cs)) {
 358                 r = -EBUSY;
 359                 goto out;
 360         }
 361         if (gpmc_cs_mem_enabled(cs))
 362                 r = adjust_resource(res, res->start & ~(size - 1), size);
 363         if (r < 0)
 364                 r = allocate_resource(&gpmc_mem_root, res, size, 0, ~0,
 365                                       size, NULL, NULL);
 366         if (r < 0)
 367                 goto out;
 368
 369         gpmc_cs_enable_mem(cs, res->start, res->end - res->start + 1);
 370         *base = res->start;
 371         gpmc_cs_set_reserved(cs, 1);
 372 out:
 373         spin_unlock(&gpmc_mem_lock);
 374         return r;
 375 }
 376 EXPORT_SYMBOL(gpmc_cs_request);
 377
 378 void gpmc_cs_free(int cs)
 379 {
 380         spin_lock(&gpmc_mem_lock);
 381         if (cs >= GPMC_CS_NUM || !gpmc_cs_reserved(cs)) {
 382                 printk(KERN_ERR "Trying to free non-reserved GPMC CS%d\n", cs);
 383                 BUG();
 384                 spin_unlock(&gpmc_mem_lock);
 385                 return;
 386         }
 387         gpmc_cs_disable_mem(cs);
 388         release_resource(&gpmc_cs_mem[cs]);
 389         gpmc_cs_set_reserved(cs, 0);
 390         spin_unlock(&gpmc_mem_lock);
 391 }
 392 EXPORT_SYMBOL(gpmc_cs_free);
 393
 394 /**
 395  * gpmc_prefetch_enable - configures and starts prefetch transfer
 396  * @cs: nand cs (chip select) number
 397  * @dma_mode: dma mode enable (1) or disable (0)
 398  * @u32_count: number of bytes to be transferred
 399  * @is_write: prefetch read(0) or write post(1) mode
 400  */
 401 int gpmc_prefetch_enable(int cs, int dma_mode,
 402                                 unsigned int u32_count, int is_write)
 403 {
 404         uint32_t prefetch_config1;
 405
 406         if (!(gpmc_read_reg(GPMC_PREFETCH_CONTROL))) {
 407                 /* Set the amount of bytes to be prefetched */
 408                 gpmc_write_reg(GPMC_PREFETCH_CONFIG2, u32_count);
 409
 410                 /* Set dma/mpu mode, the prefetch read / post write and
 411                  * enable the engine. Set which cs is has requested for.
 412                  */
 413                 prefetch_config1 = ((cs << CS_NUM_SHIFT) |
 414                                         PREFETCH_FIFOTHRESHOLD |
 415                                         ENABLE_PREFETCH |
 416                                         (dma_mode << DMA_MPU_MODE) |
 417                                         (0x1 & is_write));
 418                 gpmc_write_reg(GPMC_PREFETCH_CONFIG1, prefetch_config1);
 419         } else {
 420                 return -EBUSY;
 421         }
 422         /*  Start the prefetch engine */
 423         gpmc_write_reg(GPMC_PREFETCH_CONTROL, 0x1);
 424
 425         return 0;
 426 }
 427 EXPORT_SYMBOL(gpmc_prefetch_enable);
 428
 429 /**
 430  * gpmc_prefetch_reset - disables and stops the prefetch engine
 431  */
 432 void gpmc_prefetch_reset(void)
 433 {
 434         /* Stop the PFPW engine */
 435         gpmc_write_reg(GPMC_PREFETCH_CONTROL, 0x0);
 436
 437         /* Reset/disable the PFPW engine */
 438         gpmc_write_reg(GPMC_PREFETCH_CONFIG1, 0x0);
 439 }
 440 EXPORT_SYMBOL(gpmc_prefetch_reset);
 441
 442 /**
 443  * gpmc_prefetch_status - reads prefetch status of engine
 444  */
 445 int  gpmc_prefetch_status(void)
 446 {
 447         return gpmc_read_reg(GPMC_PREFETCH_STATUS);
 448 }
 449 EXPORT_SYMBOL(gpmc_prefetch_status);
 450
 451 static void __init gpmc_mem_init(void)
 452 {
 453         int cs;
 454         unsigned long boot_rom_space = 0;
 455
 456         /* never allocate the first page, to facilitate bug detection;
 457          * even if we didn't boot from ROM.
 458          */
 459         boot_rom_space = BOOT_ROM_SPACE;
 460         /* In apollon the CS0 is mapped as 0x0000 0000 */
 461         if (machine_is_omap_apollon())
 462                 boot_rom_space = 0;
 463         gpmc_mem_root.start = GPMC_MEM_START + boot_rom_space;
 464         gpmc_mem_root.end = GPMC_MEM_END;
 465
 466         /* Reserve all regions that has been set up by bootloader */
 467         for (cs = 0; cs < GPMC_CS_NUM; cs++) {
 468                 u32 base, size;
 469
 470                 if (!gpmc_cs_mem_enabled(cs))
 471                         continue;
 472                 gpmc_cs_get_memconf(cs, &base, &size);
 473                 if (gpmc_cs_insert_mem(cs, base, size) < 0)
 474                         BUG();
 475         }
 476 }
 477
 478 void __init gpmc_init(void)
 479 {
 480         u32 l;
 481         char *ck;
 482
 483         if (cpu_is_omap24xx()) {
 484                 ck = "core_l3_ck";
 485                 if (cpu_is_omap2420())
 486                         l = OMAP2420_GPMC_BASE;
 487                 else
 488                         l = OMAP34XX_GPMC_BASE;
 489         } else if (cpu_is_omap34xx()) {
 490                 ck = "gpmc_fck";
 491                 l = OMAP34XX_GPMC_BASE;
 492         } else if (cpu_is_omap44xx()) {
 493                 ck = "gpmc_fck";
 494                 l = OMAP44XX_GPMC_BASE;
 495         }
 496
 497         gpmc_l3_clk = clk_get(NULL, ck);
 498         if (IS_ERR(gpmc_l3_clk)) {
 499                 printk(KERN_ERR "Could not get GPMC clock %s\n", ck);
 500                 BUG();
 501         }
 502
 503         gpmc_base = ioremap(l, SZ_4K);
 504         if (!gpmc_base) {
 505                 clk_put(gpmc_l3_clk);
 506                 printk(KERN_ERR "Could not get GPMC register memory\n");
 507                 BUG();
 508         }
 509
 510         l = gpmc_read_reg(GPMC_REVISION);
 511         printk(KERN_INFO "GPMC revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 512         /* Set smart idle mode and automatic L3 clock gating */
 513         l = gpmc_read_reg(GPMC_SYSCONFIG);
 514         l &= 0x03 << 3;
 515         l |= (0x02 << 3) | (1 << 0);
 516         gpmc_write_reg(GPMC_SYSCONFIG, l);
 517         gpmc_mem_init();
 518 }