drivers/spi/atcspi200_spi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Andestech ATCSPI200 SPI controller driver.
   4  *
   5  * Copyright 2017 Andes Technology, Inc.
   6  * Author: Rick Chen (rick@andestech.com)
   7  */
   8
   9 #include <common.h>
  10 #include <clk.h>
  11 #include <log.h>
  12 #include <malloc.h>
  13 #include <spi.h>
  14 #include <asm/io.h>
  15 #include <dm.h>
  16
  17 DECLARE_GLOBAL_DATA_PTR;
  18
  19 #define MAX_TRANSFER_LEN        512
  20 #define CHUNK_SIZE              1
  21 #define SPI_TIMEOUT             0x100000
  22 #define SPI0_BUS                0
  23 #define SPI1_BUS                1
  24 #define SPI0_BASE               0xf0b00000
  25 #define SPI1_BASE               0xf0f00000
  26 #define NSPI_MAX_CS_NUM         1
  27
  28 struct atcspi200_spi_regs {
  29         u32     rev;
  30         u32     reserve1[3];
  31         u32     format;         /* 0x10 */
  32 #define DATA_LENGTH(x)  ((x-1)<<8)
  33         u32     pio;
  34         u32     reserve2[2];
  35         u32     tctrl;          /* 0x20 */
  36 #define TRAMODE_OFFSET  24
  37 #define TRAMODE_MASK    (0x0F<<TRAMODE_OFFSET)
  38 #define TRAMODE_WR_SYNC (0<<TRAMODE_OFFSET)
  39 #define TRAMODE_WO      (1<<TRAMODE_OFFSET)
  40 #define TRAMODE_RO      (2<<TRAMODE_OFFSET)
  41 #define TRAMODE_WR      (3<<TRAMODE_OFFSET)
  42 #define TRAMODE_RW      (4<<TRAMODE_OFFSET)
  43 #define TRAMODE_WDR     (5<<TRAMODE_OFFSET)
  44 #define TRAMODE_RDW     (6<<TRAMODE_OFFSET)
  45 #define TRAMODE_NONE    (7<<TRAMODE_OFFSET)
  46 #define TRAMODE_DW      (8<<TRAMODE_OFFSET)
  47 #define TRAMODE_DR      (9<<TRAMODE_OFFSET)
  48 #define WCNT_OFFSET     12
  49 #define WCNT_MASK       (0x1FF<<WCNT_OFFSET)
  50 #define RCNT_OFFSET     0
  51 #define RCNT_MASK       (0x1FF<<RCNT_OFFSET)
  52         u32     cmd;
  53         u32     addr;
  54         u32     data;
  55         u32     ctrl;           /* 0x30 */
  56 #define TXFTH_OFFSET    16
  57 #define RXFTH_OFFSET    8
  58 #define TXDMAEN         (1<<4)
  59 #define RXDMAEN         (1<<3)
  60 #define TXFRST          (1<<2)
  61 #define RXFRST          (1<<1)
  62 #define SPIRST          (1<<0)
  63         u32     status;
  64 #define TXFFL           (1<<23)
  65 #define TXEPTY          (1<<22)
  66 #define TXFVE_MASK      (0x1F<<16)
  67 #define RXFEM           (1<<14)
  68 #define RXFVE_OFFSET    (8)
  69 #define RXFVE_MASK      (0x1F<<RXFVE_OFFSET)
  70 #define SPIBSY          (1<<0)
  71         u32     inten;
  72         u32     intsta;
  73         u32     timing;         /* 0x40 */
  74 #define SCLK_DIV_MASK   0xFF
  75 };
  76
  77 struct nds_spi_slave {
  78         volatile struct atcspi200_spi_regs *regs;
  79         int             to;
  80         unsigned int    freq;
  81         ulong           clock;
  82         unsigned int    mode;
  83         u8              num_cs;
  84         unsigned int    mtiming;
  85         size_t          cmd_len;
  86         u8              cmd_buf[16];
  87         size_t          data_len;
  88         size_t          tran_len;
  89         u8              *din;
  90         u8              *dout;
  91         unsigned int    max_transfer_length;
  92 };
  93
  94 static int __atcspi200_spi_set_speed(struct nds_spi_slave *ns)
  95 {
  96         u32 tm;
  97         u8 div;
  98         tm = ns->regs->timing;
  99         tm &= ~SCLK_DIV_MASK;
 100
 101         if(ns->freq >= ns->clock)
 102                 div =0xff;
 103         else{
 104                 for (div = 0; div < 0xff; div++) {
 105                         if (ns->freq >= ns->clock / (2 * (div + 1)))
 106                                 break;
 107                 }
 108         }
 109
 110         tm |= div;
 111         ns->regs->timing = tm;
 112
 113         return 0;
 114
 115 }
 116
 117 static int __atcspi200_spi_claim_bus(struct nds_spi_slave *ns)
 118 {
 119                 unsigned int format=0;
 120                 ns->regs->ctrl |= (TXFRST|RXFRST|SPIRST);
 121                 while((ns->regs->ctrl &(TXFRST|RXFRST|SPIRST))&&(ns->to--))
 122                         if(!ns->to)
 123                                 return -EINVAL;
 124
 125                 ns->cmd_len = 0;
 126                 format = ns->mode|DATA_LENGTH(8);
 127                 ns->regs->format = format;
 128                 __atcspi200_spi_set_speed(ns);
 129
 130                 return 0;
 131 }
 132
 133 static int __atcspi200_spi_release_bus(struct nds_spi_slave *ns)
 134 {
 135         /* do nothing */
 136         return 0;
 137 }
 138
 139 static int __atcspi200_spi_start(struct nds_spi_slave *ns)
 140 {
 141         int i,olen=0;
 142         int tc = ns->regs->tctrl;
 143
 144         tc &= ~(WCNT_MASK|RCNT_MASK|TRAMODE_MASK);
 145         if ((ns->din)&&(ns->cmd_len))
 146                 tc |= TRAMODE_WR;
 147         else if (ns->din)
 148                 tc |= TRAMODE_RO;
 149         else
 150                 tc |= TRAMODE_WO;
 151
 152         if(ns->dout)
 153                 olen = ns->tran_len;
 154         tc |= (ns->cmd_len+olen-1) << WCNT_OFFSET;
 155
 156         if(ns->din)
 157                 tc |= (ns->tran_len-1) << RCNT_OFFSET;
 158
 159         ns->regs->tctrl = tc;
 160         ns->regs->cmd = 1;
 161
 162         for (i=0;i<ns->cmd_len;i++)
 163                 ns->regs->data = ns->cmd_buf[i];
 164
 165         return 0;
 166 }
 167
 168 static int __atcspi200_spi_stop(struct nds_spi_slave *ns)
 169 {
 170         ns->regs->timing = ns->mtiming;
 171         while ((ns->regs->status & SPIBSY)&&(ns->to--))
 172                 if (!ns->to)
 173                         return -EINVAL;
 174
 175         return 0;
 176 }
 177
 178 static void __nspi_espi_tx(struct nds_spi_slave *ns, const void *dout)
 179 {
 180         ns->regs->data = *(u8 *)dout;
 181 }
 182
 183 static int __nspi_espi_rx(struct nds_spi_slave *ns, void *din, unsigned int bytes)
 184 {
 185         *(u8 *)din = ns->regs->data;
 186         return bytes;
 187 }
 188
 189
 190 static int __atcspi200_spi_xfer(struct nds_spi_slave *ns,
 191                 unsigned int bitlen,  const void *data_out, void *data_in,
 192                 unsigned long flags)
 193 {
 194                 unsigned int event, rx_bytes;
 195                 const void *dout = NULL;
 196                 void *din = NULL;
 197                 int num_blks, num_chunks, max_tran_len, tran_len;
 198                 int num_bytes;
 199                 u8 *cmd_buf = ns->cmd_buf;
 200                 size_t cmd_len = ns->cmd_len;
 201                 unsigned long data_len = bitlen / 8;
 202                 int rf_cnt;
 203                 int ret = 0;
 204
 205                 max_tran_len = ns->max_transfer_length;
 206                 switch (flags) {
 207                 case SPI_XFER_BEGIN:
 208                         cmd_len = ns->cmd_len = data_len;
 209                         memcpy(cmd_buf, data_out, cmd_len);
 210                         return 0;
 211
 212                 case 0:
 213                 case SPI_XFER_END:
 214                         if (bitlen == 0) {
 215                                 return 0;
 216                         }
 217                         ns->data_len = data_len;
 218                         ns->din = (u8 *)data_in;
 219                         ns->dout = (u8 *)data_out;
 220                         break;
 221
 222                 case SPI_XFER_BEGIN | SPI_XFER_END:
 223                         ns->data_len = 0;
 224                         ns->din = 0;
 225                         ns->dout = 0;
 226                         cmd_len = ns->cmd_len = data_len;
 227                         memcpy(cmd_buf, data_out, cmd_len);
 228                         data_out = 0;
 229                         data_len = 0;
 230                         __atcspi200_spi_start(ns);
 231                         break;
 232                 }
 233                 if (data_out)
 234                         debug("spi_xfer: data_out %08X(%p) data_in %08X(%p) data_len %lu\n",
 235                               *(uint *)data_out, data_out, *(uint *)data_in,
 236                               data_in, data_len);
 237                 num_chunks = DIV_ROUND_UP(data_len, max_tran_len);
 238                 din = data_in;
 239                 dout = data_out;
 240                 while (num_chunks--) {
 241                         tran_len = min((size_t)data_len, (size_t)max_tran_len);
 242                         ns->tran_len = tran_len;
 243                         num_blks = DIV_ROUND_UP(tran_len , CHUNK_SIZE);
 244                         num_bytes = (tran_len) % CHUNK_SIZE;
 245                         if(num_bytes == 0)
 246                                 num_bytes = CHUNK_SIZE;
 247                         __atcspi200_spi_start(ns);
 248
 249                         while (num_blks) {
 250                                 event = in_le32(&ns->regs->status);
 251                                 if ((event & TXEPTY) && (data_out)) {
 252                                         __nspi_espi_tx(ns, dout);
 253                                         num_blks -= CHUNK_SIZE;
 254                                         dout += CHUNK_SIZE;
 255                                 }
 256
 257                                 if ((event & RXFVE_MASK) && (data_in)) {
 258                                         rf_cnt = ((event & RXFVE_MASK)>> RXFVE_OFFSET);
 259                                         if (rf_cnt >= CHUNK_SIZE)
 260                                                 rx_bytes = CHUNK_SIZE;
 261                                         else if (num_blks == 1 && rf_cnt == num_bytes)
 262                                                 rx_bytes = num_bytes;
 263                                         else
 264                                                 continue;
 265
 266                                         if (__nspi_espi_rx(ns, din, rx_bytes) == rx_bytes) {
 267                                                 num_blks -= CHUNK_SIZE;
 268                                                 din = (unsigned char *)din + rx_bytes;
 269                                         }
 270                                 }
 271                         }
 272
 273                         data_len -= tran_len;
 274                         if(data_len)
 275                         {
 276                                 ns->cmd_buf[1] += ((tran_len>>16)&0xff);
 277                                 ns->cmd_buf[2] += ((tran_len>>8)&0xff);
 278                                 ns->cmd_buf[3] += ((tran_len)&0xff);
 279                                 ns->data_len = data_len;
 280                         }
 281                         ret = __atcspi200_spi_stop(ns);
 282                 }
 283                 ret = __atcspi200_spi_stop(ns);
 284
 285                 return ret;
 286 }
 287
 288 static int atcspi200_spi_set_speed(struct udevice *bus, uint max_hz)
 289 {
 290         struct nds_spi_slave *ns = dev_get_priv(bus);
 291
 292         debug("%s speed %u\n", __func__, max_hz);
 293
 294         ns->freq = max_hz;
 295         __atcspi200_spi_set_speed(ns);
 296
 297         return 0;
 298 }
 299
 300 static int atcspi200_spi_set_mode(struct udevice *bus, uint mode)
 301 {
 302         struct nds_spi_slave *ns = dev_get_priv(bus);
 303
 304         debug("%s mode %u\n", __func__, mode);
 305         ns->mode = mode;
 306
 307         return 0;
 308 }
 309
 310 static int atcspi200_spi_claim_bus(struct udevice *dev)
 311 {
 312         struct dm_spi_slave_platdata *slave_plat =
 313                 dev_get_parent_platdata(dev);
 314         struct udevice *bus = dev->parent;
 315         struct nds_spi_slave *ns = dev_get_priv(bus);
 316
 317         if (slave_plat->cs >= ns->num_cs) {
 318                 printf("Invalid SPI chipselect\n");
 319                 return -EINVAL;
 320         }
 321
 322         return __atcspi200_spi_claim_bus(ns);
 323 }
 324
 325 static int atcspi200_spi_release_bus(struct udevice *dev)
 326 {
 327         struct nds_spi_slave *ns = dev_get_priv(dev->parent);
 328
 329         return __atcspi200_spi_release_bus(ns);
 330 }
 331
 332 static int atcspi200_spi_xfer(struct udevice *dev, unsigned int bitlen,
 333                             const void *dout, void *din,
 334                             unsigned long flags)
 335 {
 336         struct udevice *bus = dev->parent;
 337         struct nds_spi_slave *ns = dev_get_priv(bus);
 338
 339         return __atcspi200_spi_xfer(ns, bitlen, dout, din, flags);
 340 }
 341
 342 static int atcspi200_spi_get_clk(struct udevice *bus)
 343 {
 344         struct nds_spi_slave *ns = dev_get_priv(bus);
 345         struct clk clk;
 346         ulong clk_rate;
 347         int ret;
 348
 349         ret = clk_get_by_index(bus, 0, &clk);
 350         if (ret)
 351                 return -EINVAL;
 352
 353         clk_rate = clk_get_rate(&clk);
 354         if (!clk_rate)
 355                 return -EINVAL;
 356
 357         ns->clock = clk_rate;
 358         clk_free(&clk);
 359
 360         return 0;
 361 }
 362
 363 static int atcspi200_spi_probe(struct udevice *bus)
 364 {
 365         struct nds_spi_slave *ns = dev_get_priv(bus);
 366
 367         ns->to = SPI_TIMEOUT;
 368         ns->max_transfer_length = MAX_TRANSFER_LEN;
 369         ns->mtiming = ns->regs->timing;
 370         atcspi200_spi_get_clk(bus);
 371
 372         return 0;
 373 }
 374
 375 static int atcspi200_ofdata_to_platadata(struct udevice *bus)
 376 {
 377         struct nds_spi_slave *ns = dev_get_priv(bus);
 378         const void *blob = gd->fdt_blob;
 379         int node = dev_of_offset(bus);
 380
 381         ns->regs = map_physmem(devfdt_get_addr(bus),
 382                                  sizeof(struct atcspi200_spi_regs),
 383                                  MAP_NOCACHE);
 384         if (!ns->regs) {
 385                 printf("%s: could not map device address\n", __func__);
 386                 return -EINVAL;
 387         }
 388         ns->num_cs = fdtdec_get_int(blob, node, "num-cs", 4);
 389
 390         return 0;
 391 }
 392
 393 static const struct dm_spi_ops atcspi200_spi_ops = {
 394         .claim_bus      = atcspi200_spi_claim_bus,
 395         .release_bus    = atcspi200_spi_release_bus,
 396         .xfer           = atcspi200_spi_xfer,
 397         .set_speed      = atcspi200_spi_set_speed,
 398         .set_mode       = atcspi200_spi_set_mode,
 399 };
 400
 401 static const struct udevice_id atcspi200_spi_ids[] = {
 402         { .compatible = "andestech,atcspi200" },
 403         { }
 404 };
 405
 406 U_BOOT_DRIVER(atcspi200_spi) = {
 407         .name = "atcspi200_spi",
 408         .id = UCLASS_SPI,
 409         .of_match = atcspi200_spi_ids,
 410         .ops = &atcspi200_spi_ops,
 411         .ofdata_to_platdata = atcspi200_ofdata_to_platadata,
 412         .priv_auto_alloc_size = sizeof(struct nds_spi_slave),
 413         .probe = atcspi200_spi_probe,
 414 };