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