uboot/drivers/spi/atcspi200_spi.c
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   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
  16DECLARE_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
  27struct 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
  76struct 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
  93static 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
 116static 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
 132static int __atcspi200_spi_release_bus(struct nds_spi_slave *ns)
 133{
 134        /* do nothing */
 135        return 0;
 136}
 137
 138static 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
 167static 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
 177static void __nspi_espi_tx(struct nds_spi_slave *ns, const void *dout)
 178{
 179        ns->regs->data = *(u8 *)dout;
 180}
 181
 182static 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
 189static 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                unsigned long 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 %lu\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((size_t)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
 287static 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
 299static 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
 309static 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
 324static 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
 331static 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
 341static 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
 362static 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
 374static 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
 392static 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
 400static const struct udevice_id atcspi200_spi_ids[] = {
 401        { .compatible = "andestech,atcspi200" },
 402        { }
 403};
 404
 405U_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};
 414