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/module.h>
  18 #include <linux/blkdev.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
  37 #include <linux/stat.h>
  38
  39 #if 0
  40 #define DPRINTK(args...)        printk(args)
  41 #else
  42 #define DPRINTK(args...)
  43 #endif
  44
  45 #define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))
  46
  47 struct ip22_hostdata {
  48         struct WD33C93_hostdata wh;
  49         struct hpc_data {
  50                 dma_addr_t      dma;
  51                 void            * cpu;
  52         } hd;
  53 };
  54
  55 struct hpc_chunk {
  56         struct hpc_dma_desc desc;
  57         u32 _padding;   /* align to quadword boundary */
  58 };
  59
  60 struct Scsi_Host *sgiwd93_host;
  61 struct Scsi_Host *sgiwd93_host1;
  62
  63 /* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
  64 static inline void write_wd33c93_count(const wd33c93_regs regs,
  65                                       unsigned long value)
  66 {
  67         *regs.SASR = WD_TRANSFER_COUNT_MSB;
  68         mb();
  69         *regs.SCMD = ((value >> 16) & 0xff);
  70         *regs.SCMD = ((value >>  8) & 0xff);
  71         *regs.SCMD = ((value >>  0) & 0xff);
  72         mb();
  73 }
  74
  75 static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
  76 {
  77         unsigned long value;
  78
  79         *regs.SASR = WD_TRANSFER_COUNT_MSB;
  80         mb();
  81         value =  ((*regs.SCMD & 0xff) << 16);
  82         value |= ((*regs.SCMD & 0xff) <<  8);
  83         value |= ((*regs.SCMD & 0xff) <<  0);
  84         mb();
  85         return value;
  86 }
  87
  88 static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
  89 {
  90         struct Scsi_Host * host = (struct Scsi_Host *) dev_id;
  91         unsigned long flags;
  92
  93         spin_lock_irqsave(host->host_lock, flags);
  94         wd33c93_intr(host);
  95         spin_unlock_irqrestore(host->host_lock, flags);
  96
  97         return IRQ_HANDLED;
  98 }
  99
 100 static inline
 101 void fill_hpc_entries(struct hpc_chunk *hcp, struct scsi_cmnd *cmd, int datainp)
 102 {
 103         unsigned long len = cmd->SCp.this_residual;
 104         void *addr = cmd->SCp.ptr;
 105         dma_addr_t physaddr;
 106         unsigned long count;
 107
 108         physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
 109         cmd->SCp.dma_handle = physaddr;
 110
 111         while (len) {
 112                 /*
 113                  * even cntinfo could be up to 16383, without
 114                  * magic only 8192 works correctly
 115                  */
 116                 count = len > 8192 ? 8192 : len;
 117                 hcp->desc.pbuf = physaddr;
 118                 hcp->desc.cntinfo = count;
 119                 hcp++;
 120                 len -= count;
 121                 physaddr += count;
 122         }
 123
 124         /*
 125          * To make sure, if we trip an HPC bug, that we transfer every single
 126          * byte, we tag on an extra zero length dma descriptor at the end of
 127          * the chain.
 128          */
 129         hcp->desc.pbuf = 0;
 130         hcp->desc.cntinfo = HPCDMA_EOX;
 131 }
 132
 133 static int dma_setup(struct scsi_cmnd *cmd, int datainp)
 134 {
 135         struct ip22_hostdata *hdata = HDATA(cmd->device->host);
 136         struct hpc3_scsiregs *hregs =
 137                 (struct hpc3_scsiregs *) cmd->device->host->base;
 138         struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
 139
 140         DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
 141
 142         hdata->wh.dma_dir = datainp;
 143
 144         /*
 145          * wd33c93 shouldn't pass us bogus dma_setups, but it does:-(  The
 146          * other wd33c93 drivers deal with it the same way (which isn't that
 147          * obvious).  IMHO a better fix would be, not to do these dma setups
 148          * in the first place.
 149          */
 150         if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
 151                 return 1;
 152
 153         fill_hpc_entries(hcp, cmd, datainp);
 154
 155         DPRINTK(" HPCGO\n");
 156
 157         /* Start up the HPC. */
 158         hregs->ndptr = hdata->hd.dma;
 159         if (datainp)
 160                 hregs->ctrl = HPC3_SCTRL_ACTIVE;
 161         else
 162                 hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
 163
 164         return 0;
 165 }
 166
 167 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
 168                      int status)
 169 {
 170         struct ip22_hostdata *hdata = HDATA(instance);
 171         struct hpc3_scsiregs *hregs;
 172
 173         if (!SCpnt)
 174                 return;
 175
 176         hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
 177
 178         DPRINTK("dma_stop: status<%d> ", status);
 179
 180         /* First stop the HPC and flush it's FIFO. */
 181         if (hdata->wh.dma_dir) {
 182                 hregs->ctrl |= HPC3_SCTRL_FLUSH;
 183                 while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
 184                         barrier();
 185         }
 186         hregs->ctrl = 0;
 187         dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
 188                          SCpnt->sc_data_direction);
 189
 190         DPRINTK("\n");
 191 }
 192
 193 void sgiwd93_reset(unsigned long base)
 194 {
 195         struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
 196
 197         hregs->ctrl = HPC3_SCTRL_CRESET;
 198         udelay(50);
 199         hregs->ctrl = 0;
 200 }
 201 EXPORT_SYMBOL_GPL(sgiwd93_reset);
 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         struct 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_MHZ(20));
 250
 251         if (hdata->wh.no_sync == 0xff)
 252                 hdata->wh.no_sync = 0;
 253
 254         if (request_irq(irq, sgiwd93_intr, 0, "SGI WD93", (void *) host)) {
 255                 printk(KERN_WARNING "sgiwd93: Could not register irq %d "
 256                        "for host %d.\n", irq, unit);
 257                 goto out_free;
 258         }
 259         return host;
 260
 261 out_free:
 262         dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 263         wd33c93_release();
 264
 265 out_unregister:
 266         scsi_unregister(host);
 267
 268         return NULL;
 269 }
 270
 271 static int __init sgiwd93_detect(struct scsi_host_template *SGIblows)
 272 {
 273         int found = 0;
 274
 275         SGIblows->proc_name = "SGIWD93";
 276         sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
 277                                           &hpc3c0->scsi_chan0,
 278                                           (unsigned char *)hpc3c0->scsi0_ext);
 279         if (sgiwd93_host)
 280                 found++;
 281
 282         /* Set up second controller on the Indigo2 */
 283         if (ip22_is_fullhouse()) {
 284                 sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
 285                                           &hpc3c0->scsi_chan1,
 286                                           (unsigned char *)hpc3c0->scsi1_ext);
 287                 if (sgiwd93_host1)
 288                         found++;
 289         }
 290
 291         return found;
 292 }
 293
 294 static int sgiwd93_release(struct Scsi_Host *instance)
 295 {
 296         struct ip22_hostdata *hdata = HDATA(instance);
 297         int irq = 0;
 298
 299         if (sgiwd93_host && sgiwd93_host == instance)
 300                 irq = SGI_WD93_0_IRQ;
 301         else if (sgiwd93_host1 && sgiwd93_host1 == instance)
 302                 irq = SGI_WD93_1_IRQ;
 303
 304         free_irq(irq, sgiwd93_intr);
 305         dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 306         wd33c93_release();
 307
 308         return 1;
 309 }
 310
 311 static int sgiwd93_bus_reset(struct scsi_cmnd *cmd)
 312 {
 313         /* FIXME perform bus-specific reset */
 314
 315         /* FIXME 2: kill this function, and let midlayer fallback
 316            to the same result, calling wd33c93_host_reset() */
 317
 318         spin_lock_irq(cmd->device->host->host_lock);
 319         wd33c93_host_reset(cmd);
 320         spin_unlock_irq(cmd->device->host->host_lock);
 321
 322         return SUCCESS;
 323 }
 324
 325 /*
 326  * Kludge alert - the SCSI code calls the abort and reset method with int
 327  * arguments not with pointers.  So this is going to blow up beautyfully
 328  * on 64-bit systems with memory outside the compat address spaces.
 329  */
 330 static struct scsi_host_template driver_template = {
 331         .proc_name              = "SGIWD93",
 332         .name                   = "SGI WD93",
 333         .detect                 = sgiwd93_detect,
 334         .release                = sgiwd93_release,
 335         .queuecommand           = wd33c93_queuecommand,
 336         .eh_abort_handler       = wd33c93_abort,
 337         .eh_bus_reset_handler   = sgiwd93_bus_reset,
 338         .eh_host_reset_handler  = wd33c93_host_reset,
 339         .can_queue              = 16,
 340         .this_id                = 7,
 341         .sg_tablesize           = SG_ALL,
 342         .cmd_per_lun            = 8,
 343         .use_clustering         = DISABLE_CLUSTERING,
 344 };
 345 #include "scsi_module.c"