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