drivers/atm/firestream.h

   1 /* drivers/atm/firestream.h - FireStream 155 (MB86697) and
   2  *                            FireStream  50 (MB86695) device driver
   3  */
   4
   5 /* Written & (C) 2000 by R.E.Wolff@BitWizard.nl
   6  * Copied snippets from zatm.c by Werner Almesberger, EPFL LRC/ICA
   7  * and ambassador.c Copyright (C) 1995-1999  Madge Networks Ltd
   8  */
   9
  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 as published by
  13   the Free Software Foundation; either version 2 of the License, or
  14   (at your option) any later version.
  15
  16   This program is distributed in the hope that it will be useful,
  17   but WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19   GNU General Public License for more details.
  20
  21   You should have received a copy of the GNU General Public License
  22   along with this program; if not, write to the Free Software
  23   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24
  25   The GNU GPL is contained in /usr/doc/copyright/GPL on a Debian
  26   system and in the file COPYING in the Linux kernel source.
  27 */
  28
  29
  30 /***********************************************************************
  31  *                  first the defines for the chip.                    *
  32  ***********************************************************************/
  33
  34
  35 /********************* General chip parameters. ************************/
  36
  37 #define FS_NR_FREE_POOLS   8
  38 #define FS_NR_RX_QUEUES    4
  39
  40
  41 /********************* queues and queue access macros ******************/
  42
  43
  44 /* A queue entry. */
  45 struct FS_QENTRY {
  46         u32 cmd;
  47         u32 p0, p1, p2;
  48 };
  49
  50
  51 /* A freepool entry. */
  52 struct FS_BPENTRY {
  53         u32 flags;
  54         u32 next;
  55         u32 bsa;
  56         u32 aal_bufsize;
  57
  58         /* The hardware doesn't look at this, but we need the SKB somewhere... */
  59         struct sk_buff *skb;
  60         struct freepool *fp;
  61         struct fs_dev *dev;
  62 };
  63
  64
  65 #define STATUS_CODE(qe)  ((qe->cmd >> 22) & 0x3f)
  66
  67
  68 /* OFFSETS against the base of a QUEUE... */
  69 #define QSA     0x00
  70 #define QEA     0x04
  71 #define QRP     0x08
  72 #define QWP     0x0c
  73 #define QCNF    0x10   /* Only for Release queues! */
  74 /* Not for the transmit pending queue. */
  75
  76
  77 /* OFFSETS against the base of a FREE POOL... */
  78 #define FPCNF   0x00
  79 #define FPSA    0x04
  80 #define FPEA    0x08
  81 #define FPCNT   0x0c
  82 #define FPCTU   0x10
  83
  84 #define Q_SA(b)     (b + QSA )
  85 #define Q_EA(b)     (b + QEA )
  86 #define Q_RP(b)     (b + QRP )
  87 #define Q_WP(b)     (b + QWP )
  88 #define Q_CNF(b)    (b + QCNF)
  89
  90 #define FP_CNF(b)   (b + FPCNF)
  91 #define FP_SA(b)    (b + FPSA)
  92 #define FP_EA(b)    (b + FPEA)
  93 #define FP_CNT(b)   (b + FPCNT)
  94 #define FP_CTU(b)   (b + FPCTU)
  95
  96 /* bits in a queue register. */
  97 #define Q_FULL      0x1
  98 #define Q_EMPTY     0x2
  99 #define Q_INCWRAP   0x4
 100 #define Q_ADDR_MASK 0xfffffff0
 101
 102 /* bits in a FreePool config register */
 103 #define RBFP_RBS    (0x1 << 16)
 104 #define RBFP_RBSVAL (0x1 << 15)
 105 #define RBFP_CME    (0x1 << 12)
 106 #define RBFP_DLP    (0x1 << 11)
 107 #define RBFP_BFPWT  (0x1 <<  0)
 108
 109
 110
 111
 112 /* FireStream commands. */
 113 #define QE_CMD_NULL             (0x00 << 22)
 114 #define QE_CMD_REG_RD           (0x01 << 22)
 115 #define QE_CMD_REG_RDM          (0x02 << 22)
 116 #define QE_CMD_REG_WR           (0x03 << 22)
 117 #define QE_CMD_REG_WRM          (0x04 << 22)
 118 #define QE_CMD_CONFIG_TX        (0x05 << 22)
 119 #define QE_CMD_CONFIG_RX        (0x06 << 22)
 120 #define QE_CMD_PRP_RD           (0x07 << 22)
 121 #define QE_CMD_PRP_RDM          (0x2a << 22)
 122 #define QE_CMD_PRP_WR           (0x09 << 22)
 123 #define QE_CMD_PRP_WRM          (0x2b << 22)
 124 #define QE_CMD_RX_EN            (0x0a << 22)
 125 #define QE_CMD_RX_PURGE         (0x0b << 22)
 126 #define QE_CMD_RX_PURGE_INH     (0x0c << 22)
 127 #define QE_CMD_TX_EN            (0x0d << 22)
 128 #define QE_CMD_TX_PURGE         (0x0e << 22)
 129 #define QE_CMD_TX_PURGE_INH     (0x0f << 22)
 130 #define QE_CMD_RST_CG           (0x10 << 22)
 131 #define QE_CMD_SET_CG           (0x11 << 22)
 132 #define QE_CMD_RST_CLP          (0x12 << 22)
 133 #define QE_CMD_SET_CLP          (0x13 << 22)
 134 #define QE_CMD_OVERRIDE         (0x14 << 22)
 135 #define QE_CMD_ADD_BFP          (0x15 << 22)
 136 #define QE_CMD_DUMP_TX          (0x16 << 22)
 137 #define QE_CMD_DUMP_RX          (0x17 << 22)
 138 #define QE_CMD_LRAM_RD          (0x18 << 22)
 139 #define QE_CMD_LRAM_RDM         (0x28 << 22)
 140 #define QE_CMD_LRAM_WR          (0x19 << 22)
 141 #define QE_CMD_LRAM_WRM         (0x29 << 22)
 142 #define QE_CMD_LRAM_BSET        (0x1a << 22)
 143 #define QE_CMD_LRAM_BCLR        (0x1b << 22)
 144 #define QE_CMD_CONFIG_SEGM      (0x1c << 22)
 145 #define QE_CMD_READ_SEGM        (0x1d << 22)
 146 #define QE_CMD_CONFIG_ROUT      (0x1e << 22)
 147 #define QE_CMD_READ_ROUT        (0x1f << 22)
 148 #define QE_CMD_CONFIG_TM        (0x20 << 22)
 149 #define QE_CMD_READ_TM          (0x21 << 22)
 150 #define QE_CMD_CONFIG_TXBM      (0x22 << 22)
 151 #define QE_CMD_READ_TXBM        (0x23 << 22)
 152 #define QE_CMD_CONFIG_RXBM      (0x24 << 22)
 153 #define QE_CMD_READ_RXBM        (0x25 << 22)
 154 #define QE_CMD_CONFIG_REAS      (0x26 << 22)
 155 #define QE_CMD_READ_REAS        (0x27 << 22)
 156
 157 #define QE_TRANSMIT_DE          (0x0 << 30)
 158 #define QE_CMD_LINKED           (0x1 << 30)
 159 #define QE_CMD_IMM              (0x2 << 30)
 160 #define QE_CMD_IMM_INQ          (0x3 << 30)
 161
 162 #define TD_EPI                  (0x1 << 27)
 163 #define TD_COMMAND              (0x1 << 28)
 164
 165 #define TD_DATA                 (0x0 << 29)
 166 #define TD_RM_CELL              (0x1 << 29)
 167 #define TD_OAM_CELL             (0x2 << 29)
 168 #define TD_OAM_CELL_SEGMENT     (0x3 << 29)
 169
 170 #define TD_BPI                  (0x1 << 20)
 171
 172 #define FP_FLAGS_EPI            (0x1 << 27)
 173
 174
 175 #define TX_PQ(i)  (0x00  + (i) * 0x10)
 176 #define TXB_RQ    (0x20)
 177 #define ST_Q      (0x48)
 178 #define RXB_FP(i) (0x90  + (i) * 0x14)
 179 #define RXB_RQ(i) (0x134 + (i) * 0x14)
 180
 181
 182 #define TXQ_HP 0
 183 #define TXQ_LP 1
 184
 185 /* Phew. You don't want to know how many revisions these simple queue
 186  * address macros went through before I got them nice and compact as
 187  * they are now. -- REW
 188  */
 189
 190
 191 /* And now for something completely different:
 192  * The rest of the registers... */
 193
 194
 195 #define CMDR0 0x34
 196 #define CMDR1 0x38
 197 #define CMDR2 0x3c
 198 #define CMDR3 0x40
 199
 200
 201 #define SARMODE0     0x5c
 202
 203 #define SARMODE0_TXVCS_0    (0x0 << 0)
 204 #define SARMODE0_TXVCS_1k   (0x1 << 0)
 205 #define SARMODE0_TXVCS_2k   (0x2 << 0)
 206 #define SARMODE0_TXVCS_4k   (0x3 << 0)
 207 #define SARMODE0_TXVCS_8k   (0x4 << 0)
 208 #define SARMODE0_TXVCS_16k  (0x5 << 0)
 209 #define SARMODE0_TXVCS_32k  (0x6 << 0)
 210 #define SARMODE0_TXVCS_64k  (0x7 << 0)
 211 #define SARMODE0_TXVCS_32   (0x8 << 0)
 212
 213 #define SARMODE0_ABRVCS_0   (0x0 << 4)
 214 #define SARMODE0_ABRVCS_512 (0x1 << 4)
 215 #define SARMODE0_ABRVCS_1k  (0x2 << 4)
 216 #define SARMODE0_ABRVCS_2k  (0x3 << 4)
 217 #define SARMODE0_ABRVCS_4k  (0x4 << 4)
 218 #define SARMODE0_ABRVCS_8k  (0x5 << 4)
 219 #define SARMODE0_ABRVCS_16k (0x6 << 4)
 220 #define SARMODE0_ABRVCS_32k (0x7 << 4)
 221 #define SARMODE0_ABRVCS_32  (0x9 << 4) /* The others are "8", this one really has to
 222                                           be 9. Tell me you don't believe me. -- REW */
 223
 224 #define SARMODE0_RXVCS_0    (0x0 << 8)
 225 #define SARMODE0_RXVCS_1k   (0x1 << 8)
 226 #define SARMODE0_RXVCS_2k   (0x2 << 8)
 227 #define SARMODE0_RXVCS_4k   (0x3 << 8)
 228 #define SARMODE0_RXVCS_8k   (0x4 << 8)
 229 #define SARMODE0_RXVCS_16k  (0x5 << 8)
 230 #define SARMODE0_RXVCS_32k  (0x6 << 8)
 231 #define SARMODE0_RXVCS_64k  (0x7 << 8)
 232 #define SARMODE0_RXVCS_32   (0x8 << 8)
 233
 234 #define SARMODE0_CALSUP_1  (0x0 << 12)
 235 #define SARMODE0_CALSUP_2  (0x1 << 12)
 236 #define SARMODE0_CALSUP_3  (0x2 << 12)
 237 #define SARMODE0_CALSUP_4  (0x3 << 12)
 238
 239 #define SARMODE0_PRPWT_FS50_0  (0x0 << 14)
 240 #define SARMODE0_PRPWT_FS50_2  (0x1 << 14)
 241 #define SARMODE0_PRPWT_FS50_5  (0x2 << 14)
 242 #define SARMODE0_PRPWT_FS50_11 (0x3 << 14)
 243
 244 #define SARMODE0_PRPWT_FS155_0 (0x0 << 14)
 245 #define SARMODE0_PRPWT_FS155_1 (0x1 << 14)
 246 #define SARMODE0_PRPWT_FS155_2 (0x2 << 14)
 247 #define SARMODE0_PRPWT_FS155_3 (0x3 << 14)
 248
 249 #define SARMODE0_SRTS0     (0x1 << 23)
 250 #define SARMODE0_SRTS1     (0x1 << 24)
 251
 252 #define SARMODE0_RUN       (0x1 << 25)
 253
 254 #define SARMODE0_UNLOCK    (0x1 << 26)
 255 #define SARMODE0_CWRE      (0x1 << 27)
 256
 257
 258 #define SARMODE0_INTMODE_READCLEAR          (0x0 << 28)
 259 #define SARMODE0_INTMODE_READNOCLEAR        (0x1 << 28)
 260 #define SARMODE0_INTMODE_READNOCLEARINHIBIT (0x2 << 28)
 261 #define SARMODE0_INTMODE_READCLEARINHIBIT   (0x3 << 28)  /* Tell me you don't believe me. */
 262
 263 #define SARMODE0_GINT      (0x1 << 30)
 264 #define SARMODE0_SHADEN    (0x1 << 31)
 265
 266
 267 #define SARMODE1     0x60
 268
 269
 270 #define SARMODE1_TRTL_SHIFT 0   /* Program to 0 */
 271 #define SARMODE1_RRTL_SHIFT 4   /* Program to 0 */
 272
 273 #define SARMODE1_TAGM       (0x1 <<  8)  /* Program to 0 */
 274
 275 #define SARMODE1_HECM0      (0x1 <<  9)
 276 #define SARMODE1_HECM1      (0x1 << 10)
 277 #define SARMODE1_HECM2      (0x1 << 11)
 278
 279 #define SARMODE1_GFCE       (0x1 << 14)
 280 #define SARMODE1_GFCR       (0x1 << 15)
 281 #define SARMODE1_PMS        (0x1 << 18)
 282 #define SARMODE1_GPRI       (0x1 << 19)
 283 #define SARMODE1_GPAS       (0x1 << 20)
 284 #define SARMODE1_GVAS       (0x1 << 21)
 285 #define SARMODE1_GNAM       (0x1 << 22)
 286 #define SARMODE1_GPLEN      (0x1 << 23)
 287 #define SARMODE1_DUMPE      (0x1 << 24)
 288 #define SARMODE1_OAMCRC     (0x1 << 25)
 289 #define SARMODE1_DCOAM      (0x1 << 26)
 290 #define SARMODE1_DCRM       (0x1 << 27)
 291 #define SARMODE1_TSTLP      (0x1 << 28)
 292 #define SARMODE1_DEFHEC     (0x1 << 29)
 293
 294
 295 #define ISR      0x64
 296 #define IUSR     0x68
 297 #define IMR      0x6c
 298
 299 #define ISR_LPCO          (0x1 <<  0)
 300 #define ISR_DPCO          (0x1 <<  1)
 301 #define ISR_RBRQ0_W       (0x1 <<  2)
 302 #define ISR_RBRQ1_W       (0x1 <<  3)
 303 #define ISR_RBRQ2_W       (0x1 <<  4)
 304 #define ISR_RBRQ3_W       (0x1 <<  5)
 305 #define ISR_RBRQ0_NF      (0x1 <<  6)
 306 #define ISR_RBRQ1_NF      (0x1 <<  7)
 307 #define ISR_RBRQ2_NF      (0x1 <<  8)
 308 #define ISR_RBRQ3_NF      (0x1 <<  9)
 309 #define ISR_BFP_SC        (0x1 << 10)
 310 #define ISR_INIT          (0x1 << 11)
 311 #define ISR_INIT_ERR      (0x1 << 12) /* Documented as "reserved" */
 312 #define ISR_USCEO         (0x1 << 13)
 313 #define ISR_UPEC0         (0x1 << 14)
 314 #define ISR_VPFCO         (0x1 << 15)
 315 #define ISR_CRCCO         (0x1 << 16)
 316 #define ISR_HECO          (0x1 << 17)
 317 #define ISR_TBRQ_W        (0x1 << 18)
 318 #define ISR_TBRQ_NF       (0x1 << 19)
 319 #define ISR_CTPQ_E        (0x1 << 20)
 320 #define ISR_GFC_C0        (0x1 << 21)
 321 #define ISR_PCI_FTL       (0x1 << 22)
 322 #define ISR_CSQ_W         (0x1 << 23)
 323 #define ISR_CSQ_NF        (0x1 << 24)
 324 #define ISR_EXT_INT       (0x1 << 25)
 325 #define ISR_RXDMA_S       (0x1 << 26)
 326
 327
 328 #define TMCONF 0x78
 329 /* Bits? */
 330
 331
 332 #define CALPRESCALE 0x7c
 333 /* Bits? */
 334
 335 #define CELLOSCONF 0x84
 336 #define CELLOSCONF_COTS   (0x1 << 28)
 337 #define CELLOSCONF_CEN    (0x1 << 27)
 338 #define CELLOSCONF_SC8    (0x3 << 24)
 339 #define CELLOSCONF_SC4    (0x2 << 24)
 340 #define CELLOSCONF_SC2    (0x1 << 24)
 341 #define CELLOSCONF_SC1    (0x0 << 24)
 342
 343 #define CELLOSCONF_COBS   (0x1 << 16)
 344 #define CELLOSCONF_COPK   (0x1 <<  8)
 345 #define CELLOSCONF_COST   (0x1 <<  0)
 346 /* Bits? */
 347
 348 #define RAS0 0x1bc
 349 #define RAS0_DCD_XHLT (0x1 << 31)
 350
 351 #define RAS0_VPSEL    (0x1 << 16)
 352 #define RAS0_VCSEL    (0x1 <<  0)
 353
 354 #define RAS1 0x1c0
 355 #define RAS1_UTREG    (0x1 << 5)
 356
 357
 358 #define DMAMR 0x1cc
 359 #define DMAMR_TX_MODE_FULL (0x0 << 0)
 360 #define DMAMR_TX_MODE_PART (0x1 << 0)
 361 #define DMAMR_TX_MODE_NONE (0x2 << 0) /* And 3 */
 362
 363
 364
 365 #define RAS2 0x280
 366
 367 #define RAS2_NNI  (0x1 << 0)
 368 #define RAS2_USEL (0x1 << 1)
 369 #define RAS2_UBS  (0x1 << 2)
 370
 371
 372
 373 struct fs_transmit_config {
 374         u32 flags;
 375         u32 atm_hdr;
 376         u32 TMC[4];
 377         u32 spec;
 378         u32 rtag[3];
 379 };
 380
 381 #define TC_FLAGS_AAL5      (0x0 << 29)
 382 #define TC_FLAGS_TRANSPARENT_PAYLOAD (0x1 << 29)
 383 #define TC_FLAGS_TRANSPARENT_CELL    (0x2 << 29)
 384 #define TC_FLAGS_STREAMING (0x1 << 28)
 385 #define TC_FLAGS_PACKET    (0x0)
 386 #define TC_FLAGS_TYPE_ABR  (0x0 << 22)
 387 #define TC_FLAGS_TYPE_CBR  (0x1 << 22)
 388 #define TC_FLAGS_TYPE_VBR  (0x2 << 22)
 389 #define TC_FLAGS_TYPE_UBR  (0x3 << 22)
 390 #define TC_FLAGS_CAL0      (0x0 << 20)
 391 #define TC_FLAGS_CAL1      (0x1 << 20)
 392 #define TC_FLAGS_CAL2      (0x2 << 20)
 393 #define TC_FLAGS_CAL3      (0x3 << 20)
 394
 395
 396 #define RC_FLAGS_NAM        (0x1 << 13)
 397 #define RC_FLAGS_RXBM_PSB   (0x0 << 14)
 398 #define RC_FLAGS_RXBM_CIF   (0x1 << 14)
 399 #define RC_FLAGS_RXBM_PMB   (0x2 << 14)
 400 #define RC_FLAGS_RXBM_STR   (0x4 << 14)
 401 #define RC_FLAGS_RXBM_SAF   (0x6 << 14)
 402 #define RC_FLAGS_RXBM_POS   (0x6 << 14)
 403 #define RC_FLAGS_BFPS       (0x1 << 17)
 404
 405 #define RC_FLAGS_BFPS_BFP   (0x1 << 17)
 406
 407 #define RC_FLAGS_BFPS_BFP0  (0x0 << 17)
 408 #define RC_FLAGS_BFPS_BFP1  (0x1 << 17)
 409 #define RC_FLAGS_BFPS_BFP2  (0x2 << 17)
 410 #define RC_FLAGS_BFPS_BFP3  (0x3 << 17)
 411 #define RC_FLAGS_BFPS_BFP4  (0x4 << 17)
 412 #define RC_FLAGS_BFPS_BFP5  (0x5 << 17)
 413 #define RC_FLAGS_BFPS_BFP6  (0x6 << 17)
 414 #define RC_FLAGS_BFPS_BFP7  (0x7 << 17)
 415 #define RC_FLAGS_BFPS_BFP01 (0x8 << 17)
 416 #define RC_FLAGS_BFPS_BFP23 (0x9 << 17)
 417 #define RC_FLAGS_BFPS_BFP45 (0xa << 17)
 418 #define RC_FLAGS_BFPS_BFP67 (0xb << 17)
 419 #define RC_FLAGS_BFPS_BFP07 (0xc << 17)
 420 #define RC_FLAGS_BFPS_BFP27 (0xd << 17)
 421 #define RC_FLAGS_BFPS_BFP47 (0xe << 17)
 422
 423 #define RC_FLAGS_BFPS       (0x1 << 17)
 424 #define RC_FLAGS_BFPP       (0x1 << 21)
 425 #define RC_FLAGS_TEVC       (0x1 << 22)
 426 #define RC_FLAGS_TEP        (0x1 << 23)
 427 #define RC_FLAGS_AAL5       (0x0 << 24)
 428 #define RC_FLAGS_TRANSP     (0x1 << 24)
 429 #define RC_FLAGS_TRANSC     (0x2 << 24)
 430 #define RC_FLAGS_ML         (0x1 << 27)
 431 #define RC_FLAGS_TRBRM      (0x1 << 28)
 432 #define RC_FLAGS_PRI        (0x1 << 29)
 433 #define RC_FLAGS_HOAM       (0x1 << 30)
 434 #define RC_FLAGS_CRC10      (0x1 << 31)
 435
 436
 437 #define RAC 0x1c8
 438 #define RAM 0x1c4
 439
 440
 441
 442 /************************************************************************
 443  *         Then the datastructures that the DRIVER uses.                *
 444  ************************************************************************/
 445
 446 #define TXQ_NENTRIES  32
 447 #define RXRQ_NENTRIES 1024
 448
 449
 450 struct fs_vcc {
 451         int channo;
 452         wait_queue_head_t close_wait;
 453         struct sk_buff *last_skb;
 454 };
 455
 456
 457 struct queue {
 458         struct FS_QENTRY *sa, *ea;
 459         int offset;
 460 };
 461
 462 struct freepool {
 463         int offset;
 464         int bufsize;
 465         int nr_buffers;
 466         int n;
 467 };
 468
 469
 470 struct fs_dev {
 471         struct fs_dev *next;            /* other FS devices */
 472         int flags;
 473
 474         unsigned char irq;              /* IRQ */
 475         struct pci_dev *pci_dev;        /* PCI stuff */
 476         struct atm_dev *atm_dev;
 477         struct timer_list timer;
 478
 479         unsigned long hw_base;          /* mem base address */
 480         void __iomem *base;             /* Mapping of base address */
 481         int channo;
 482         unsigned long channel_mask;
 483
 484         struct queue    hp_txq, lp_txq, tx_relq, st_q;
 485         struct freepool rx_fp[FS_NR_FREE_POOLS];
 486         struct queue    rx_rq[FS_NR_RX_QUEUES];
 487
 488         int nchannels;
 489         struct atm_vcc **atm_vccs;
 490         void *tx_inuse;
 491         int ntxpckts;
 492 };
 493
 494
 495
 496
 497 /* Number of channesl that the FS50 supports. */
 498 #define FS50_CHANNEL_BITS  5
 499 #define FS50_NR_CHANNELS      (1 << FS50_CHANNEL_BITS)
 500
 501
 502 #define FS_DEV(atm_dev) ((struct fs_dev *) (atm_dev)->dev_data)
 503 #define FS_VCC(atm_vcc) ((struct fs_vcc *) (atm_vcc)->dev_data)
 504
 505
 506 #define FS_IS50  0x1
 507 #define FS_IS155 0x2
 508
 509 #define IS_FS50(dev)  (dev->flags & FS_IS50)
 510 #define IS_FS155(dev) (dev->flags & FS_IS155)
 511
 512 /* Within limits this is user-configurable. */
 513 /* Note: Currently the sum (10 -> 1k channels) is hardcoded in the driver. */
 514 #define FS155_VPI_BITS 4
 515 #define FS155_VCI_BITS 6
 516
 517 #define FS155_CHANNEL_BITS  (FS155_VPI_BITS + FS155_VCI_BITS)
 518 #define FS155_NR_CHANNELS   (1 << FS155_CHANNEL_BITS)