| 1 | /* mba.c 4.8 81/02/21 */ |
| 2 | |
| 3 | /* |
| 4 | * Massbus driver; arbitrates massbusses through device driver routines |
| 5 | * and provides common functions. |
| 6 | */ |
| 7 | int mbadebug = 0; |
| 8 | #define dprintf if (mbadebug) printf |
| 9 | |
| 10 | #include "../h/param.h" |
| 11 | #include "../h/systm.h" |
| 12 | #include "../h/dk.h" |
| 13 | #include "../h/buf.h" |
| 14 | #include "../h/conf.h" |
| 15 | #include "../h/dir.h" |
| 16 | #include "../h/user.h" |
| 17 | #include "../h/proc.h" |
| 18 | #include "../h/map.h" |
| 19 | #include "../h/pte.h" |
| 20 | #include "../h/mba.h" |
| 21 | #include "../h/mtpr.h" |
| 22 | #include "../h/vm.h" |
| 23 | |
| 24 | /* |
| 25 | * Start activity on a massbus device. |
| 26 | * We are given the device's mba_info structure and activate |
| 27 | * the device via the unit start routine. The unit start |
| 28 | * routine may indicate that it is finished (e.g. if the operation |
| 29 | * was a ``sense'' on a tape drive), that the (multi-ported) unit |
| 30 | * is busy (we will get an interrupt later), that it started the |
| 31 | * unit (e.g. for a non-data transfer operation), or that it has |
| 32 | * set up a data transfer operation and we should start the massbus adaptor. |
| 33 | */ |
| 34 | mbustart(mi) |
| 35 | register struct mba_info *mi; |
| 36 | { |
| 37 | register struct mba_drv *mdp; /* drive registers */ |
| 38 | register struct buf *bp; /* i/o operation at head of queue */ |
| 39 | register struct mba_hd *mhp; /* header for mba device is on */ |
| 40 | |
| 41 | dprintf("enter mbustart\n"); |
| 42 | loop: |
| 43 | /* |
| 44 | * Get the first thing to do off device queue. |
| 45 | */ |
| 46 | bp = mi->mi_tab.b_actf; |
| 47 | if (bp == NULL) |
| 48 | return; |
| 49 | mdp = mi->mi_drv; |
| 50 | /* |
| 51 | * Since we clear attentions on the drive when we are |
| 52 | * finished processing it, the fact that an attention |
| 53 | * status shows indicated confusion in the hardware or our logic. |
| 54 | */ |
| 55 | if (mdp->mbd_as & (1 << mi->mi_drive)) { |
| 56 | printf("mbustart: ata on for %d\n", mi->mi_drive); |
| 57 | mdp->mbd_as = 1 << mi->mi_drive; |
| 58 | } |
| 59 | /* |
| 60 | * Let the drivers unit start routine have at it |
| 61 | * and then process the request further, per its instructions. |
| 62 | */ |
| 63 | switch ((*mi->mi_driver->md_ustart)(mi)) { |
| 64 | |
| 65 | case MBU_NEXT: /* request is complete (e.g. ``sense'') */ |
| 66 | dprintf("mbu_next\n"); |
| 67 | mi->mi_tab.b_active = 0; |
| 68 | mi->mi_tab.b_actf = bp->av_forw; |
| 69 | iodone(bp); |
| 70 | goto loop; |
| 71 | |
| 72 | case MBU_DODATA: /* all ready to do data transfer */ |
| 73 | dprintf("mbu_dodata\n"); |
| 74 | /* |
| 75 | * Queue the device mba_info structure on the massbus |
| 76 | * mba_hd structure for processing as soon as the |
| 77 | * data path is available. |
| 78 | */ |
| 79 | mhp = mi->mi_hd; |
| 80 | mi->mi_forw = NULL; |
| 81 | if (mhp->mh_actf == NULL) |
| 82 | mhp->mh_actf = mi; |
| 83 | else |
| 84 | mhp->mh_actl->mi_forw = mi; |
| 85 | mhp->mh_actl = mi; |
| 86 | /* |
| 87 | * If data path is idle, start transfer now. |
| 88 | * In any case the device is ``active'' waiting for the |
| 89 | * data to transfer. |
| 90 | */ |
| 91 | if (mhp->mh_active == 0) |
| 92 | mbstart(mhp); |
| 93 | mi->mi_tab.b_active = 1; |
| 94 | return; |
| 95 | |
| 96 | case MBU_STARTED: /* driver started a non-data transfer */ |
| 97 | dprintf("mbu_started\n"); |
| 98 | /* |
| 99 | * Mark device busy during non-data transfer |
| 100 | * and count this as a ``seek'' on the device. |
| 101 | */ |
| 102 | if (mi->mi_dk >= 0) |
| 103 | dk_seek[mi->mi_dk]++; |
| 104 | mi->mi_tab.b_active = 1; |
| 105 | return; |
| 106 | |
| 107 | case MBU_BUSY: /* dual port drive busy */ |
| 108 | dprintf("mbu_busy\n"); |
| 109 | /* |
| 110 | * We mark the device structure so that when an |
| 111 | * interrupt occurs we will know to restart the unit. |
| 112 | */ |
| 113 | mi->mi_tab.b_flags |= B_BUSY; |
| 114 | return; |
| 115 | |
| 116 | default: |
| 117 | panic("mbustart"); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * Start an i/o operation on the massbus specified by the argument. |
| 123 | * We peel the first operation off its queue and insure that the drive |
| 124 | * is present and on-line. We then use the drivers start routine |
| 125 | * (if any) to prepare the drive, setup the massbus map for the transfer |
| 126 | * and start the transfer. |
| 127 | */ |
| 128 | mbstart(mhp) |
| 129 | register struct mba_hd *mhp; |
| 130 | { |
| 131 | register struct mba_info *mi; |
| 132 | struct buf *bp; |
| 133 | register struct mba_regs *mbp; |
| 134 | |
| 135 | dprintf("mbstart\n"); |
| 136 | loop: |
| 137 | /* |
| 138 | * Look for an operation at the front of the queue. |
| 139 | */ |
| 140 | if ((mi = mhp->mh_actf) == NULL) { |
| 141 | dprintf("nothing to do\n"); |
| 142 | return; |
| 143 | } |
| 144 | if ((bp = mi->mi_tab.b_actf) == NULL) { |
| 145 | dprintf("nothing on actf\n"); |
| 146 | mhp->mh_actf = mi->mi_forw; |
| 147 | goto loop; |
| 148 | } |
| 149 | /* |
| 150 | * If this device isn't present and on-line, then |
| 151 | * we screwed up, and can't really do the operation. |
| 152 | */ |
| 153 | if ((mi->mi_drv->mbd_ds & (MBD_DPR|MBD_MOL)) != (MBD_DPR|MBD_MOL)) { |
| 154 | dprintf("not on line ds %x\n", mi->mi_drv->mbd_ds); |
| 155 | mi->mi_tab.b_actf = bp->av_forw; |
| 156 | bp->b_flags |= B_ERROR; |
| 157 | iodone(bp); |
| 158 | goto loop; |
| 159 | } |
| 160 | /* |
| 161 | * We can do the operation; mark the massbus active |
| 162 | * and let the device start routine setup any necessary |
| 163 | * device state for the transfer (e.g. desired cylinder, etc |
| 164 | * on disks). |
| 165 | */ |
| 166 | mhp->mh_active = 1; |
| 167 | if (mi->mi_driver->md_start) { |
| 168 | dprintf("md_start\n"); |
| 169 | (*mi->mi_driver->md_start)(mi); |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * Setup the massbus control and map registers and start |
| 174 | * the transfer. |
| 175 | */ |
| 176 | dprintf("start mba\n"); |
| 177 | mbp = mi->mi_mba; |
| 178 | mbp->mba_sr = -1; /* conservative */ |
| 179 | mbp->mba_var = mbasetup(mi); |
| 180 | mbp->mba_bcr = -bp->b_bcount; |
| 181 | mi->mi_drv->mbd_cs1 = |
| 182 | (bp->b_flags & B_READ) ? MBD_RCOM|MBD_GO : MBD_WCOM|MBD_GO; |
| 183 | if (mi->mi_dk >= 0) { |
| 184 | dk_busy |= 1 << mi->mi_dk; |
| 185 | dk_xfer[mi->mi_dk]++; |
| 186 | dk_wds[mi->mi_dk] += bp->b_bcount >> 6; |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | /* |
| 191 | * Take an interrupt off of massbus mbanum, |
| 192 | * and dispatch to drivers as appropriate. |
| 193 | */ |
| 194 | mbintr(mbanum) |
| 195 | int mbanum; |
| 196 | { |
| 197 | register struct mba_hd *mhp = &mba_hd[mbanum]; |
| 198 | register struct mba_regs *mbp = mhp->mh_mba; |
| 199 | register struct mba_info *mi; |
| 200 | register struct buf *bp; |
| 201 | register int drive; |
| 202 | int mbastat, as; |
| 203 | |
| 204 | /* |
| 205 | * Read out the massbus status register |
| 206 | * and attention status register and clear |
| 207 | * the bits in same by writing them back. |
| 208 | */ |
| 209 | mbastat = mbp->mba_sr; |
| 210 | mbp->mba_sr = mbastat; |
| 211 | /* note: the mbd_as register is shared between drives */ |
| 212 | as = mbp->mba_drv[0].mbd_as; |
| 213 | mbp->mba_drv[0].mbd_as = as; |
| 214 | dprintf("mbintr mbastat %x as %x\n", mbastat, as); |
| 215 | |
| 216 | /* |
| 217 | * Disable interrupts from the massbus adapter |
| 218 | * for the duration of the operation of the massbus |
| 219 | * driver, so that spurious interrupts won't be generated. |
| 220 | */ |
| 221 | mbp->mba_cr &= ~MBAIE; |
| 222 | |
| 223 | /* |
| 224 | * If the mba was active, process the data transfer |
| 225 | * complete interrupt; otherwise just process units which |
| 226 | * are now finished. |
| 227 | */ |
| 228 | if (mhp->mh_active) { |
| 229 | if ((mbastat & MBS_DTCMP) == 0) { |
| 230 | printf("mbintr(%d),b_active,no DTCMP!\n", mbanum); |
| 231 | goto doattn; |
| 232 | } |
| 233 | /* |
| 234 | * Clear attention status for drive whose data |
| 235 | * transfer completed, and give the dtint driver |
| 236 | * routine a chance to say what is next. |
| 237 | */ |
| 238 | mi = mhp->mh_actf; |
| 239 | as &= ~(1 << mi->mi_drive); |
| 240 | dk_busy &= ~(1 << mi->mi_dk); |
| 241 | bp = mi->mi_tab.b_actf; |
| 242 | switch((*mi->mi_driver->md_dtint)(mi, mbastat)) { |
| 243 | |
| 244 | case MBD_DONE: /* all done, for better or worse */ |
| 245 | dprintf("mbd_done\n"); |
| 246 | /* |
| 247 | * Flush request from drive queue. |
| 248 | */ |
| 249 | mi->mi_tab.b_errcnt = 0; |
| 250 | mi->mi_tab.b_actf = bp->av_forw; |
| 251 | iodone(bp); |
| 252 | /* fall into... */ |
| 253 | case MBD_RETRY: /* attempt the operation again */ |
| 254 | dprintf("mbd_retry\n"); |
| 255 | /* |
| 256 | * Dequeue data transfer from massbus queue; |
| 257 | * if there is still a i/o request on the device |
| 258 | * queue then start the next operation on the device. |
| 259 | * (Common code for DONE and RETRY). |
| 260 | */ |
| 261 | mhp->mh_active = 0; |
| 262 | mi->mi_tab.b_active = 0; |
| 263 | mhp->mh_actf = mi->mi_forw; |
| 264 | if (mi->mi_tab.b_actf) |
| 265 | mbustart(mi); |
| 266 | break; |
| 267 | |
| 268 | case MBD_RESTARTED: /* driver restarted op (ecc, e.g.) |
| 269 | dprintf("mbd_restarted\n"); |
| 270 | /* |
| 271 | * Note that mp->b_active is still on. |
| 272 | */ |
| 273 | break; |
| 274 | |
| 275 | default: |
| 276 | panic("mbaintr"); |
| 277 | } |
| 278 | } else { |
| 279 | dprintf("!dtcmp\n"); |
| 280 | if (mbastat & MBS_DTCMP) |
| 281 | printf("mbaintr,DTCMP,!b_active\n"); |
| 282 | } |
| 283 | doattn: |
| 284 | /* |
| 285 | * Service drives which require attention |
| 286 | * after non-data-transfer operations. |
| 287 | */ |
| 288 | for (drive = 0; as && drive < 8; drive++) |
| 289 | if (as & (1 << drive)) { |
| 290 | dprintf("service as %d\n", drive); |
| 291 | as &= ~(1 << drive); |
| 292 | /* |
| 293 | * Consistency check the implied attention, |
| 294 | * to make sure the drive should have interrupted. |
| 295 | */ |
| 296 | mi = mhp->mh_mbip[drive]; |
| 297 | if (mi == NULL) |
| 298 | goto random; /* no such drive */ |
| 299 | if (mi->mi_tab.b_active == 0 && |
| 300 | (mi->mi_tab.b_flags&B_BUSY) == 0) |
| 301 | goto random; /* not active */ |
| 302 | if ((bp = mi->mi_tab.b_actf) == NULL) { |
| 303 | /* nothing doing */ |
| 304 | random: |
| 305 | printf("random mbaintr %d %d\n",mbanum,drive); |
| 306 | continue; |
| 307 | } |
| 308 | /* |
| 309 | * If this interrupt wasn't a notification that |
| 310 | * a dual ported drive is available, and if the |
| 311 | * driver has a handler for non-data transfer |
| 312 | * interrupts, give it a chance to tell us that |
| 313 | * the operation needs to be redone |
| 314 | */ |
| 315 | if ((mi->mi_tab.b_flags&B_BUSY) == 0 && |
| 316 | mi->mi_driver->md_ndint) { |
| 317 | mi->mi_tab.b_active = 0; |
| 318 | switch((*mi->mi_driver->md_ndint)(mi)) { |
| 319 | |
| 320 | case MBN_DONE: |
| 321 | dprintf("mbn_done\n"); |
| 322 | /* |
| 323 | * Non-data transfer interrupt |
| 324 | * completed i/o request's processing. |
| 325 | */ |
| 326 | mi->mi_tab.b_errcnt = 0; |
| 327 | mi->mi_tab.b_actf = bp->av_forw; |
| 328 | iodone(bp); |
| 329 | /* fall into... */ |
| 330 | case MBN_RETRY: |
| 331 | dprintf("mbn_retry\n"); |
| 332 | if (mi->mi_tab.b_actf) |
| 333 | mbustart(mi); |
| 334 | break; |
| 335 | |
| 336 | default: |
| 337 | panic("mbintr ndint"); |
| 338 | } |
| 339 | } else |
| 340 | mbustart(mi); |
| 341 | } |
| 342 | /* |
| 343 | * If there is an operation available and |
| 344 | * the massbus isn't active, get it going. |
| 345 | */ |
| 346 | if (mhp->mh_actf && !mhp->mh_active) |
| 347 | mbstart(mhp); |
| 348 | mbp->mba_cr |= MBAIE; |
| 349 | } |
| 350 | |
| 351 | /* |
| 352 | * Setup the mapping registers for a transfer. |
| 353 | */ |
| 354 | mbasetup(mi) |
| 355 | register struct mba_info *mi; |
| 356 | { |
| 357 | register struct mba_regs *mbap = mi->mi_mba; |
| 358 | struct buf *bp = mi->mi_tab.b_actf; |
| 359 | register int i; |
| 360 | int npf; |
| 361 | unsigned v; |
| 362 | register struct pte *pte, *io; |
| 363 | int o; |
| 364 | int vaddr; |
| 365 | struct proc *rp; |
| 366 | |
| 367 | io = mbap->mba_map; |
| 368 | v = btop(bp->b_un.b_addr); |
| 369 | o = (int)bp->b_un.b_addr & PGOFSET; |
| 370 | npf = btoc(bp->b_bcount + o); |
| 371 | rp = bp->b_flags&B_DIRTY ? &proc[2] : bp->b_proc; |
| 372 | vaddr = o; |
| 373 | if (bp->b_flags & B_UAREA) { |
| 374 | for (i = 0; i < UPAGES; i++) { |
| 375 | if (rp->p_addr[i].pg_pfnum == 0) |
| 376 | panic("mba: zero upage"); |
| 377 | *(int *)io++ = rp->p_addr[i].pg_pfnum | PG_V; |
| 378 | } |
| 379 | } else if ((bp->b_flags & B_PHYS) == 0) { |
| 380 | pte = &Sysmap[btop(((int)bp->b_un.b_addr)&0x7fffffff)]; |
| 381 | while (--npf >= 0) |
| 382 | *(int *)io++ = pte++->pg_pfnum | PG_V; |
| 383 | } else { |
| 384 | if (bp->b_flags & B_PAGET) |
| 385 | pte = &Usrptmap[btokmx((struct pte *)bp->b_un.b_addr)]; |
| 386 | else |
| 387 | pte = vtopte(rp, v); |
| 388 | while (--npf >= 0) { |
| 389 | if (pte->pg_pfnum == 0) |
| 390 | panic("mba, zero entry"); |
| 391 | *(int *)io++ = pte++->pg_pfnum | PG_V; |
| 392 | } |
| 393 | } |
| 394 | *(int *)io++ = 0; |
| 395 | return (vaddr); |
| 396 | } |