drivers/ram/stm32_sdram.c

   1 /*
   2  * (C) Copyright 2017
   3  * Vikas Manocha, <[email protected]>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <clk.h>
  10 #include <dm.h>
  11 #include <ram.h>
  12 #include <asm/io.h>
  13
  14 DECLARE_GLOBAL_DATA_PTR;
  15
  16 struct stm32_fmc_regs {
  17         /* 0x0 */
  18         u32 bcr1;       /* NOR/PSRAM Chip select control register 1 */
  19         u32 btr1;       /* SRAM/NOR-Flash Chip select timing register 1 */
  20         u32 bcr2;       /* NOR/PSRAM Chip select Control register 2 */
  21         u32 btr2;       /* SRAM/NOR-Flash Chip select timing register 2 */
  22         u32 bcr3;       /* NOR/PSRAMChip select Control register 3 */
  23         u32 btr3;       /* SRAM/NOR-Flash Chip select timing register 3 */
  24         u32 bcr4;       /* NOR/PSRAM Chip select Control register 4 */
  25         u32 btr4;       /* SRAM/NOR-Flash Chip select timing register 4 */
  26         u32 reserved1[24];
  27
  28         /* 0x80 */
  29         u32 pcr;        /* NAND Flash control register */
  30         u32 sr;         /* FIFO status and interrupt register */
  31         u32 pmem;       /* Common memory space timing register */
  32         u32 patt;       /* Attribute memory space timing registers  */
  33         u32 reserved2[1];
  34         u32 eccr;       /* ECC result registers */
  35         u32 reserved3[27];
  36
  37         /* 0x104 */
  38         u32 bwtr1;      /* SRAM/NOR-Flash write timing register 1 */
  39         u32 reserved4[1];
  40         u32 bwtr2;      /* SRAM/NOR-Flash write timing register 2 */
  41         u32 reserved5[1];
  42         u32 bwtr3;      /* SRAM/NOR-Flash write timing register 3 */
  43         u32 reserved6[1];
  44         u32 bwtr4;      /* SRAM/NOR-Flash write timing register 4 */
  45         u32 reserved7[8];
  46
  47         /* 0x140 */
  48         u32 sdcr1;      /* SDRAM Control register 1 */
  49         u32 sdcr2;      /* SDRAM Control register 2 */
  50         u32 sdtr1;      /* SDRAM Timing register 1 */
  51         u32 sdtr2;      /* SDRAM Timing register 2 */
  52         u32 sdcmr;      /* SDRAM Mode register */
  53         u32 sdrtr;      /* SDRAM Refresh timing register */
  54         u32 sdsr;       /* SDRAM Status register */
  55 };
  56
  57 /*
  58  * NOR/PSRAM Control register BCR1
  59  * FMC controller Enable, only availabe for H7
  60  */
  61 #define FMC_BCR1_FMCEN          BIT(31)
  62
  63 /* Control register SDCR */
  64 #define FMC_SDCR_RPIPE_SHIFT    13      /* RPIPE bit shift */
  65 #define FMC_SDCR_RBURST_SHIFT   12      /* RBURST bit shift */
  66 #define FMC_SDCR_SDCLK_SHIFT    10      /* SDRAM clock divisor shift */
  67 #define FMC_SDCR_WP_SHIFT       9       /* Write protection shift */
  68 #define FMC_SDCR_CAS_SHIFT      7       /* CAS latency shift */
  69 #define FMC_SDCR_NB_SHIFT       6       /* Number of banks shift */
  70 #define FMC_SDCR_MWID_SHIFT     4       /* Memory width shift */
  71 #define FMC_SDCR_NR_SHIFT       2       /* Number of row address bits shift */
  72 #define FMC_SDCR_NC_SHIFT       0       /* Number of col address bits shift */
  73
  74 /* Timings register SDTR */
  75 #define FMC_SDTR_TMRD_SHIFT     0       /* Load mode register to active */
  76 #define FMC_SDTR_TXSR_SHIFT     4       /* Exit self-refresh time */
  77 #define FMC_SDTR_TRAS_SHIFT     8       /* Self-refresh time */
  78 #define FMC_SDTR_TRC_SHIFT      12      /* Row cycle delay */
  79 #define FMC_SDTR_TWR_SHIFT      16      /* Recovery delay */
  80 #define FMC_SDTR_TRP_SHIFT      20      /* Row precharge delay */
  81 #define FMC_SDTR_TRCD_SHIFT     24      /* Row-to-column delay */
  82
  83 #define FMC_SDCMR_NRFS_SHIFT    5
  84
  85 #define FMC_SDCMR_MODE_NORMAL           0
  86 #define FMC_SDCMR_MODE_START_CLOCK      1
  87 #define FMC_SDCMR_MODE_PRECHARGE        2
  88 #define FMC_SDCMR_MODE_AUTOREFRESH      3
  89 #define FMC_SDCMR_MODE_WRITE_MODE       4
  90 #define FMC_SDCMR_MODE_SELFREFRESH      5
  91 #define FMC_SDCMR_MODE_POWERDOWN        6
  92
  93 #define FMC_SDCMR_BANK_1                BIT(4)
  94 #define FMC_SDCMR_BANK_2                BIT(3)
  95
  96 #define FMC_SDCMR_MODE_REGISTER_SHIFT   9
  97
  98 #define FMC_SDSR_BUSY                   BIT(5)
  99
 100 #define FMC_BUSY_WAIT(regs)     do { \
 101                 __asm__ __volatile__ ("dsb" : : : "memory"); \
 102                 while (regs->sdsr & FMC_SDSR_BUSY) \
 103                         ; \
 104         } while (0)
 105
 106 struct stm32_sdram_control {
 107         u8 no_columns;
 108         u8 no_rows;
 109         u8 memory_width;
 110         u8 no_banks;
 111         u8 cas_latency;
 112         u8 sdclk;
 113         u8 rd_burst;
 114         u8 rd_pipe_delay;
 115 };
 116
 117 struct stm32_sdram_timing {
 118         u8 tmrd;
 119         u8 txsr;
 120         u8 tras;
 121         u8 trc;
 122         u8 trp;
 123         u8 twr;
 124         u8 trcd;
 125 };
 126 enum stm32_fmc_bank {
 127         SDRAM_BANK1,
 128         SDRAM_BANK2,
 129         MAX_SDRAM_BANK,
 130 };
 131
 132 enum stm32_fmc_family {
 133         STM32F7_FMC,
 134         STM32H7_FMC,
 135 };
 136
 137 struct bank_params {
 138         struct stm32_sdram_control *sdram_control;
 139         struct stm32_sdram_timing *sdram_timing;
 140         u32 sdram_ref_count;
 141         enum stm32_fmc_bank target_bank;
 142 };
 143
 144 struct stm32_sdram_params {
 145         struct stm32_fmc_regs *base;
 146         u8 no_sdram_banks;
 147         struct bank_params bank_params[MAX_SDRAM_BANK];
 148         enum stm32_fmc_family family;
 149 };
 150
 151 #define SDRAM_MODE_BL_SHIFT     0
 152 #define SDRAM_MODE_CAS_SHIFT    4
 153 #define SDRAM_MODE_BL           0
 154
 155 int stm32_sdram_init(struct udevice *dev)
 156 {
 157         struct stm32_sdram_params *params = dev_get_platdata(dev);
 158         struct stm32_sdram_control *control;
 159         struct stm32_sdram_timing *timing;
 160         struct stm32_fmc_regs *regs = params->base;
 161         enum stm32_fmc_bank target_bank;
 162         u32 ctb; /* SDCMR register: Command Target Bank */
 163         u32 ref_count;
 164         u8 i;
 165
 166         /* disable the FMC controller */
 167         if (params->family == STM32H7_FMC)
 168                 clrbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
 169
 170         for (i = 0; i < params->no_sdram_banks; i++) {
 171                 control = params->bank_params[i].sdram_control;
 172                 timing = params->bank_params[i].sdram_timing;
 173                 target_bank = params->bank_params[i].target_bank;
 174                 ref_count = params->bank_params[i].sdram_ref_count;
 175
 176                 writel(control->sdclk << FMC_SDCR_SDCLK_SHIFT
 177                         | control->cas_latency << FMC_SDCR_CAS_SHIFT
 178                         | control->no_banks << FMC_SDCR_NB_SHIFT
 179                         | control->memory_width << FMC_SDCR_MWID_SHIFT
 180                         | control->no_rows << FMC_SDCR_NR_SHIFT
 181                         | control->no_columns << FMC_SDCR_NC_SHIFT
 182                         | control->rd_pipe_delay << FMC_SDCR_RPIPE_SHIFT
 183                         | control->rd_burst << FMC_SDCR_RBURST_SHIFT,
 184                         &regs->sdcr1);
 185
 186                 if (target_bank == SDRAM_BANK2)
 187                         writel(control->cas_latency << FMC_SDCR_CAS_SHIFT
 188                                 | control->no_banks << FMC_SDCR_NB_SHIFT
 189                                 | control->memory_width << FMC_SDCR_MWID_SHIFT
 190                                 | control->no_rows << FMC_SDCR_NR_SHIFT
 191                                 | control->no_columns << FMC_SDCR_NC_SHIFT,
 192                                 &regs->sdcr2);
 193
 194                 writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
 195                         | timing->trp << FMC_SDTR_TRP_SHIFT
 196                         | timing->twr << FMC_SDTR_TWR_SHIFT
 197                         | timing->trc << FMC_SDTR_TRC_SHIFT
 198                         | timing->tras << FMC_SDTR_TRAS_SHIFT
 199                         | timing->txsr << FMC_SDTR_TXSR_SHIFT
 200                         | timing->tmrd << FMC_SDTR_TMRD_SHIFT,
 201                         &regs->sdtr1);
 202
 203                 if (target_bank == SDRAM_BANK2)
 204                         writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
 205                                 | timing->trp << FMC_SDTR_TRP_SHIFT
 206                                 | timing->twr << FMC_SDTR_TWR_SHIFT
 207                                 | timing->trc << FMC_SDTR_TRC_SHIFT
 208                                 | timing->tras << FMC_SDTR_TRAS_SHIFT
 209                                 | timing->txsr << FMC_SDTR_TXSR_SHIFT
 210                                 | timing->tmrd << FMC_SDTR_TMRD_SHIFT,
 211                                 &regs->sdtr2);
 212
 213                 if (target_bank == SDRAM_BANK1)
 214                         ctb = FMC_SDCMR_BANK_1;
 215                 else
 216                         ctb = FMC_SDCMR_BANK_2;
 217
 218                 writel(ctb | FMC_SDCMR_MODE_START_CLOCK, &regs->sdcmr);
 219                 udelay(200);    /* 200 us delay, page 10, "Power-Up" */
 220                 FMC_BUSY_WAIT(regs);
 221
 222                 writel(ctb | FMC_SDCMR_MODE_PRECHARGE, &regs->sdcmr);
 223                 udelay(100);
 224                 FMC_BUSY_WAIT(regs);
 225
 226                 writel((ctb | FMC_SDCMR_MODE_AUTOREFRESH | 7 << FMC_SDCMR_NRFS_SHIFT),
 227                        &regs->sdcmr);
 228                 udelay(100);
 229                 FMC_BUSY_WAIT(regs);
 230
 231                 writel(ctb | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT
 232                        | control->cas_latency << SDRAM_MODE_CAS_SHIFT)
 233                        << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE,
 234                        &regs->sdcmr);
 235                 udelay(100);
 236                 FMC_BUSY_WAIT(regs);
 237
 238                 writel(ctb | FMC_SDCMR_MODE_NORMAL, &regs->sdcmr);
 239                 FMC_BUSY_WAIT(regs);
 240
 241                 /* Refresh timer */
 242                 writel(ref_count << 1, &regs->sdrtr);
 243         }
 244
 245         /* enable the FMC controller */
 246         if (params->family == STM32H7_FMC)
 247                 setbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
 248
 249         return 0;
 250 }
 251
 252 static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
 253 {
 254         struct stm32_sdram_params *params = dev_get_platdata(dev);
 255         struct bank_params *bank_params;
 256         ofnode bank_node;
 257         char *bank_name;
 258         u8 bank = 0;
 259
 260         dev_for_each_subnode(bank_node, dev) {
 261                 /* extract the bank index from DT */
 262                 bank_name = (char *)ofnode_get_name(bank_node);
 263                 strsep(&bank_name, "@");
 264                 if (!bank_name) {
 265                         pr_err("missing sdram bank index");
 266                         return -EINVAL;
 267                 }
 268
 269                 bank_params = &params->bank_params[bank];
 270                 strict_strtoul(bank_name, 10,
 271                                (long unsigned int *)&bank_params->target_bank);
 272
 273                 if (bank_params->target_bank >= MAX_SDRAM_BANK) {
 274                         pr_err("Found bank %d , but only bank 0 and 1 are supported",
 275                               bank_params->target_bank);
 276                         return -EINVAL;
 277                 }
 278
 279                 debug("Find bank %s %u\n", bank_name, bank_params->target_bank);
 280
 281                 params->bank_params[bank].sdram_control =
 282                         (struct stm32_sdram_control *)
 283                          ofnode_read_u8_array_ptr(bank_node,
 284                                                   "st,sdram-control",
 285                                                   sizeof(struct stm32_sdram_control));
 286
 287                 if (!params->bank_params[bank].sdram_control) {
 288                         pr_err("st,sdram-control not found for %s",
 289                               ofnode_get_name(bank_node));
 290                         return -EINVAL;
 291                 }
 292
 293
 294                 params->bank_params[bank].sdram_timing =
 295                         (struct stm32_sdram_timing *)
 296                          ofnode_read_u8_array_ptr(bank_node,
 297                                                   "st,sdram-timing",
 298                                                   sizeof(struct stm32_sdram_timing));
 299
 300                 if (!params->bank_params[bank].sdram_timing) {
 301                         pr_err("st,sdram-timing not found for %s",
 302                               ofnode_get_name(bank_node));
 303                         return -EINVAL;
 304                 }
 305
 306
 307                 bank_params->sdram_ref_count = ofnode_read_u32_default(bank_node,
 308                                                 "st,sdram-refcount", 8196);
 309                 bank++;
 310         }
 311
 312         params->no_sdram_banks = bank;
 313         debug("%s, no of banks = %d\n", __func__, params->no_sdram_banks);
 314
 315         return 0;
 316 }
 317
 318 static int stm32_fmc_probe(struct udevice *dev)
 319 {
 320         struct stm32_sdram_params *params = dev_get_platdata(dev);
 321         int ret;
 322         fdt_addr_t addr;
 323
 324         addr = dev_read_addr(dev);
 325         if (addr == FDT_ADDR_T_NONE)
 326                 return -EINVAL;
 327
 328         params->base = (struct stm32_fmc_regs *)addr;
 329         params->family = dev_get_driver_data(dev);
 330
 331 #ifdef CONFIG_CLK
 332         struct clk clk;
 333
 334         ret = clk_get_by_index(dev, 0, &clk);
 335         if (ret < 0)
 336                 return ret;
 337
 338         ret = clk_enable(&clk);
 339
 340         if (ret) {
 341                 dev_err(dev, "failed to enable clock\n");
 342                 return ret;
 343         }
 344 #endif
 345         ret = stm32_sdram_init(dev);
 346         if (ret)
 347                 return ret;
 348
 349         return 0;
 350 }
 351
 352 static int stm32_fmc_get_info(struct udevice *dev, struct ram_info *info)
 353 {
 354         return 0;
 355 }
 356
 357 static struct ram_ops stm32_fmc_ops = {
 358         .get_info = stm32_fmc_get_info,
 359 };
 360
 361 static const struct udevice_id stm32_fmc_ids[] = {
 362         { .compatible = "st,stm32-fmc", .data = STM32F7_FMC },
 363         { .compatible = "st,stm32h7-fmc", .data = STM32H7_FMC },
 364         { }
 365 };
 366
 367 U_BOOT_DRIVER(stm32_fmc) = {
 368         .name = "stm32_fmc",
 369         .id = UCLASS_RAM,
 370         .of_match = stm32_fmc_ids,
 371         .ops = &stm32_fmc_ops,
 372         .ofdata_to_platdata = stm32_fmc_ofdata_to_platdata,
 373         .probe = stm32_fmc_probe,
 374         .platdata_auto_alloc_size = sizeof(struct stm32_sdram_params),
 375 };