drivers/scsi/sgiwd93.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   7  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
   8  * Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
   9  * Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
  10  *
  11  * (In all truth, Jed Schimmel wrote all this code.)
  12  */
  13 #include <linux/init.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/types.h>
  16 #include <linux/mm.h>
  17 #include <linux/blkdev.h>
  18 #include <linux/version.h>
  19 #include <linux/delay.h>
  20 #include <linux/dma-mapping.h>
  21 #include <linux/spinlock.h>
  22
  23 #include <asm/page.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/sgialib.h>
  26 #include <asm/sgi/sgi.h>
  27 #include <asm/sgi/mc.h>
  28 #include <asm/sgi/hpc3.h>
  29 #include <asm/sgi/ip22.h>
  30 #include <asm/irq.h>
  31 #include <asm/io.h>
  32
  33 #include "scsi.h"
  34 #include <scsi/scsi_host.h>
  35 #include "wd33c93.h"
  36 #include "sgiwd93.h"
  37
  38 #include <linux/stat.h>
  39
  40 #if 0
  41 #define DPRINTK(args...)        printk(args)
  42 #else
  43 #define DPRINTK(args...)
  44 #endif
  45
  46 #define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))
  47
  48 struct ip22_hostdata {
  49         struct WD33C93_hostdata wh;
  50         struct hpc_data {
  51                 dma_addr_t      dma;
  52                 void            * cpu;
  53         } hd;
  54 };
  55
  56 struct hpc_chunk {
  57         struct hpc_dma_desc desc;
  58         u32 _padding;   /* align to quadword boundary */
  59 };
  60
  61 struct Scsi_Host *sgiwd93_host;
  62 struct Scsi_Host *sgiwd93_host1;
  63
  64 /* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
  65 static inline void write_wd33c93_count(const wd33c93_regs regs,
  66                                       unsigned long value)
  67 {
  68         *regs.SASR = WD_TRANSFER_COUNT_MSB;
  69         mb();
  70         *regs.SCMD = ((value >> 16) & 0xff);
  71         *regs.SCMD = ((value >>  8) & 0xff);
  72         *regs.SCMD = ((value >>  0) & 0xff);
  73         mb();
  74 }
  75
  76 static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
  77 {
  78         unsigned long value;
  79
  80         *regs.SASR = WD_TRANSFER_COUNT_MSB;
  81         mb();
  82         value =  ((*regs.SCMD & 0xff) << 16);
  83         value |= ((*regs.SCMD & 0xff) <<  8);
  84         value |= ((*regs.SCMD & 0xff) <<  0);
  85         mb();
  86         return value;
  87 }
  88
  89 static irqreturn_t sgiwd93_intr(int irq, void *dev_id, struct pt_regs *regs)
  90 {
  91         struct Scsi_Host * host = (struct Scsi_Host *) dev_id;
  92         unsigned long flags;
  93
  94         spin_lock_irqsave(host->host_lock, flags);
  95         wd33c93_intr(host);
  96         spin_unlock_irqrestore(host->host_lock, flags);
  97
  98         return IRQ_HANDLED;
  99 }
 100
 101 static inline
 102 void fill_hpc_entries(struct hpc_chunk *hcp, Scsi_Cmnd *cmd, int datainp)
 103 {
 104         unsigned long len = cmd->SCp.this_residual;
 105         void *addr = cmd->SCp.ptr;
 106         dma_addr_t physaddr;
 107         unsigned long count;
 108
 109         physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
 110         cmd->SCp.dma_handle = physaddr;
 111
 112         while (len) {
 113                 /*
 114                  * even cntinfo could be up to 16383, without
 115                  * magic only 8192 works correctly
 116                  */
 117                 count = len > 8192 ? 8192 : len;
 118                 hcp->desc.pbuf = physaddr;
 119                 hcp->desc.cntinfo = count;
 120                 hcp++;
 121                 len -= count;
 122                 physaddr += count;
 123         }
 124
 125         /*
 126          * To make sure, if we trip an HPC bug, that we transfer every single
 127          * byte, we tag on an extra zero length dma descriptor at the end of
 128          * the chain.
 129          */
 130         hcp->desc.pbuf = 0;
 131         hcp->desc.cntinfo = HPCDMA_EOX;
 132 }
 133
 134 static int dma_setup(Scsi_Cmnd *cmd, int datainp)
 135 {
 136         struct ip22_hostdata *hdata = HDATA(cmd->device->host);
 137         struct hpc3_scsiregs *hregs =
 138                 (struct hpc3_scsiregs *) cmd->device->host->base;
 139         struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
 140
 141         DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
 142
 143         hdata->wh.dma_dir = datainp;
 144
 145         /*
 146          * wd33c93 shouldn't pass us bogus dma_setups, but it does:-(  The
 147          * other wd33c93 drivers deal with it the same way (which isn't that
 148          * obvious).  IMHO a better fix would be, not to do these dma setups
 149          * in the first place.
 150          */
 151         if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
 152                 return 1;
 153
 154         fill_hpc_entries(hcp, cmd, datainp);
 155
 156         DPRINTK(" HPCGO\n");
 157
 158         /* Start up the HPC. */
 159         hregs->ndptr = hdata->hd.dma;
 160         if (datainp)
 161                 hregs->ctrl = HPC3_SCTRL_ACTIVE;
 162         else
 163                 hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
 164
 165         return 0;
 166 }
 167
 168 static void dma_stop(struct Scsi_Host *instance, Scsi_Cmnd *SCpnt,
 169                      int status)
 170 {
 171         struct ip22_hostdata *hdata = HDATA(instance);
 172         struct hpc3_scsiregs *hregs;
 173
 174         if (!SCpnt)
 175                 return;
 176
 177         hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
 178
 179         DPRINTK("dma_stop: status<%d> ", status);
 180
 181         /* First stop the HPC and flush it's FIFO. */
 182         if (hdata->wh.dma_dir) {
 183                 hregs->ctrl |= HPC3_SCTRL_FLUSH;
 184                 while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
 185                         barrier();
 186         }
 187         hregs->ctrl = 0;
 188         dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
 189                          SCpnt->sc_data_direction);
 190
 191         DPRINTK("\n");
 192 }
 193
 194 void sgiwd93_reset(unsigned long base)
 195 {
 196         struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
 197
 198         hregs->ctrl = HPC3_SCTRL_CRESET;
 199         udelay(50);
 200         hregs->ctrl = 0;
 201 }
 202
 203 static inline void init_hpc_chain(struct hpc_data *hd)
 204 {
 205         struct hpc_chunk *hcp = (struct hpc_chunk *) hd->cpu;
 206         struct hpc_chunk *dma = (struct hpc_chunk *) hd->dma;
 207         unsigned long start, end;
 208
 209         start = (unsigned long) hcp;
 210         end = start + PAGE_SIZE;
 211         while (start < end) {
 212                 hcp->desc.pnext = (u32) (dma + 1);
 213                 hcp->desc.cntinfo = HPCDMA_EOX;
 214                 hcp++; dma++;
 215                 start += sizeof(struct hpc_chunk);
 216         };
 217         hcp--;
 218         hcp->desc.pnext = hd->dma;
 219 }
 220
 221 static struct Scsi_Host * __init sgiwd93_setup_scsi(
 222         Scsi_Host_Template *SGIblows, int unit, int irq,
 223         struct hpc3_scsiregs *hregs, unsigned char *wdregs)
 224 {
 225         struct ip22_hostdata *hdata;
 226         struct Scsi_Host *host;
 227         wd33c93_regs regs;
 228
 229         host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
 230         if (!host)
 231                 return NULL;
 232
 233         host->base = (unsigned long) hregs;
 234         host->irq = irq;
 235
 236         hdata = HDATA(host);
 237         hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
 238                                            GFP_KERNEL);
 239         if (!hdata->hd.cpu) {
 240                 printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
 241                        "host %d buffer.\n", unit);
 242                 goto out_unregister;
 243         }
 244         init_hpc_chain(&hdata->hd);
 245
 246         regs.SASR = wdregs + 3;
 247         regs.SCMD = wdregs + 7;
 248
 249         wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);
 250
 251         hdata->wh.no_sync = 0;
 252
 253         if (request_irq(irq, sgiwd93_intr, 0, "SGI WD93", (void *) host)) {
 254                 printk(KERN_WARNING "sgiwd93: Could not register irq %d "
 255                        "for host %d.\n", irq, unit);
 256                 goto out_free;
 257         }
 258         return host;
 259
 260 out_free:
 261         dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 262         wd33c93_release();
 263
 264 out_unregister:
 265         scsi_unregister(host);
 266
 267         return NULL;
 268 }
 269
 270 int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
 271 {
 272         int found = 0;
 273
 274         SGIblows->proc_name = "SGIWD93";
 275         sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
 276                                           &hpc3c0->scsi_chan0,
 277                                           (unsigned char *)hpc3c0->scsi0_ext);
 278         if (sgiwd93_host)
 279                 found++;
 280
 281         /* Set up second controller on the Indigo2 */
 282         if (ip22_is_fullhouse()) {
 283                 sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
 284                                           &hpc3c0->scsi_chan1,
 285                                           (unsigned char *)hpc3c0->scsi1_ext);
 286                 if (sgiwd93_host1)
 287                         found++;
 288         }
 289
 290         return found;
 291 }
 292
 293 int sgiwd93_release(struct Scsi_Host *instance)
 294 {
 295         struct ip22_hostdata *hdata = HDATA(instance);
 296         int irq = 0;
 297
 298         if (sgiwd93_host && sgiwd93_host == instance)
 299                 irq = SGI_WD93_0_IRQ;
 300         else if (sgiwd93_host1 && sgiwd93_host1 == instance)
 301                 irq = SGI_WD93_1_IRQ;
 302
 303         free_irq(irq, sgiwd93_intr);
 304         dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 305         wd33c93_release();
 306
 307         return 1;
 308 }
 309
 310 static int sgiwd93_bus_reset(Scsi_Cmnd *cmd)
 311 {
 312         /* FIXME perform bus-specific reset */
 313
 314         /* FIXME 2: kill this function, and let midlayer fallback
 315            to the same result, calling wd33c93_host_reset() */
 316
 317         spin_lock_irq(cmd->device->host->host_lock);
 318         wd33c93_host_reset(cmd);
 319         spin_unlock_irq(cmd->device->host->host_lock);
 320
 321         return SUCCESS;
 322 }
 323
 324 /*
 325  * Kludge alert - the SCSI code calls the abort and reset method with int
 326  * arguments not with pointers.  So this is going to blow up beautyfully
 327  * on 64-bit systems with memory outside the compat address spaces.
 328  */
 329 static Scsi_Host_Template driver_template = {
 330         .proc_name              = "SGIWD93",
 331         .name                   = "SGI WD93",
 332         .detect                 = sgiwd93_detect,
 333         .release                = sgiwd93_release,
 334         .queuecommand           = wd33c93_queuecommand,
 335         .eh_abort_handler       = wd33c93_abort,
 336         .eh_bus_reset_handler   = sgiwd93_bus_reset,
 337         .eh_host_reset_handler  = wd33c93_host_reset,
 338         .can_queue              = CAN_QUEUE,
 339         .this_id                = 7,
 340         .sg_tablesize           = SG_ALL,
 341         .cmd_per_lun            = CMD_PER_LUN,
 342         .use_clustering         = DISABLE_CLUSTERING,
 343 };
 344 #include "scsi_module.c"