drivers/scsi/a3000.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/types.h>
   3 #include <linux/mm.h>
   4 #include <linux/ioport.h>
   5 #include <linux/init.h>
   6 #include <linux/slab.h>
   7 #include <linux/spinlock.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/module.h>
  11
  12 #include <asm/page.h>
  13 #include <asm/amigaints.h>
  14 #include <asm/amigahw.h>
  15
  16 #include <scsi/scsi.h>
  17 #include <scsi/scsi_cmnd.h>
  18 #include <scsi/scsi_device.h>
  19 #include <scsi/scsi_eh.h>
  20 #include <scsi/scsi_tcq.h>
  21 #include "wd33c93.h"
  22 #include "a3000.h"
  23
  24
  25 struct a3000_hostdata {
  26         struct WD33C93_hostdata wh;
  27         struct a3000_scsiregs *regs;
  28 };
  29
  30 static irqreturn_t a3000_intr(int irq, void *data)
  31 {
  32         struct Scsi_Host *instance = data;
  33         struct a3000_hostdata *hdata = shost_priv(instance);
  34         unsigned int status = hdata->regs->ISTR;
  35         unsigned long flags;
  36
  37         if (!(status & ISTR_INT_P))
  38                 return IRQ_NONE;
  39         if (status & ISTR_INTS) {
  40                 spin_lock_irqsave(instance->host_lock, flags);
  41                 wd33c93_intr(instance);
  42                 spin_unlock_irqrestore(instance->host_lock, flags);
  43                 return IRQ_HANDLED;
  44         }
  45         pr_warn("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status);
  46         return IRQ_NONE;
  47 }
  48
  49 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
  50 {
  51         struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
  52         struct Scsi_Host *instance = cmd->device->host;
  53         struct a3000_hostdata *hdata = shost_priv(instance);
  54         struct WD33C93_hostdata *wh = &hdata->wh;
  55         struct a3000_scsiregs *regs = hdata->regs;
  56         unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
  57         unsigned long addr = virt_to_bus(scsi_pointer->ptr);
  58
  59         /*
  60          * if the physical address has the wrong alignment, or if
  61          * physical address is bad, or if it is a write and at the
  62          * end of a physical memory chunk, then allocate a bounce
  63          * buffer
  64          */
  65         if (addr & A3000_XFER_MASK) {
  66                 wh->dma_bounce_len = (scsi_pointer->this_residual + 511) & ~0x1ff;
  67                 wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
  68                                                 GFP_KERNEL);
  69
  70                 /* can't allocate memory; use PIO */
  71                 if (!wh->dma_bounce_buffer) {
  72                         wh->dma_bounce_len = 0;
  73                         return 1;
  74                 }
  75
  76                 if (!dir_in) {
  77                         /* copy to bounce buffer for a write */
  78                         memcpy(wh->dma_bounce_buffer, scsi_pointer->ptr,
  79                                scsi_pointer->this_residual);
  80                 }
  81
  82                 addr = virt_to_bus(wh->dma_bounce_buffer);
  83         }
  84
  85         /* setup dma direction */
  86         if (!dir_in)
  87                 cntr |= CNTR_DDIR;
  88
  89         /* remember direction */
  90         wh->dma_dir = dir_in;
  91
  92         regs->CNTR = cntr;
  93
  94         /* setup DMA *physical* address */
  95         regs->ACR = addr;
  96
  97         if (dir_in) {
  98                 /* invalidate any cache */
  99                 cache_clear(addr, scsi_pointer->this_residual);
 100         } else {
 101                 /* push any dirty cache */
 102                 cache_push(addr, scsi_pointer->this_residual);
 103         }
 104
 105         /* start DMA */
 106         mb();                   /* make sure setup is completed */
 107         regs->ST_DMA = 1;
 108         mb();                   /* make sure DMA has started before next IO */
 109
 110         /* return success */
 111         return 0;
 112 }
 113
 114 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
 115                      int status)
 116 {
 117         struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
 118         struct a3000_hostdata *hdata = shost_priv(instance);
 119         struct WD33C93_hostdata *wh = &hdata->wh;
 120         struct a3000_scsiregs *regs = hdata->regs;
 121
 122         /* disable SCSI interrupts */
 123         unsigned short cntr = CNTR_PDMD;
 124
 125         if (!wh->dma_dir)
 126                 cntr |= CNTR_DDIR;
 127
 128         regs->CNTR = cntr;
 129         mb();                   /* make sure CNTR is updated before next IO */
 130
 131         /* flush if we were reading */
 132         if (wh->dma_dir) {
 133                 regs->FLUSH = 1;
 134                 mb();           /* don't allow prefetch */
 135                 while (!(regs->ISTR & ISTR_FE_FLG))
 136                         barrier();
 137                 mb();           /* no IO until FLUSH is done */
 138         }
 139
 140         /* clear a possible interrupt */
 141         /* I think that this CINT is only necessary if you are
 142          * using the terminal count features.   HM 7 Mar 1994
 143          */
 144         regs->CINT = 1;
 145
 146         /* stop DMA */
 147         regs->SP_DMA = 1;
 148         mb();                   /* make sure DMA is stopped before next IO */
 149
 150         /* restore the CONTROL bits (minus the direction flag) */
 151         regs->CNTR = CNTR_PDMD | CNTR_INTEN;
 152         mb();                   /* make sure CNTR is updated before next IO */
 153
 154         /* copy from a bounce buffer, if necessary */
 155         if (status && wh->dma_bounce_buffer) {
 156                 if (SCpnt) {
 157                         if (wh->dma_dir && SCpnt)
 158                                 memcpy(scsi_pointer->ptr, wh->dma_bounce_buffer,
 159                                        scsi_pointer->this_residual);
 160                         kfree(wh->dma_bounce_buffer);
 161                         wh->dma_bounce_buffer = NULL;
 162                         wh->dma_bounce_len = 0;
 163                 } else {
 164                         kfree(wh->dma_bounce_buffer);
 165                         wh->dma_bounce_buffer = NULL;
 166                         wh->dma_bounce_len = 0;
 167                 }
 168         }
 169 }
 170
 171 static struct scsi_host_template amiga_a3000_scsi_template = {
 172         .module                 = THIS_MODULE,
 173         .name                   = "Amiga 3000 built-in SCSI",
 174         .show_info              = wd33c93_show_info,
 175         .write_info             = wd33c93_write_info,
 176         .proc_name              = "A3000",
 177         .queuecommand           = wd33c93_queuecommand,
 178         .eh_abort_handler       = wd33c93_abort,
 179         .eh_host_reset_handler  = wd33c93_host_reset,
 180         .can_queue              = CAN_QUEUE,
 181         .this_id                = 7,
 182         .sg_tablesize           = SG_ALL,
 183         .cmd_per_lun            = CMD_PER_LUN,
 184         .cmd_size               = sizeof(struct scsi_pointer),
 185 };
 186
 187 static int __init amiga_a3000_scsi_probe(struct platform_device *pdev)
 188 {
 189         struct resource *res;
 190         struct Scsi_Host *instance;
 191         int error;
 192         struct a3000_scsiregs *regs;
 193         wd33c93_regs wdregs;
 194         struct a3000_hostdata *hdata;
 195
 196         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 197         if (!res)
 198                 return -ENODEV;
 199
 200         if (!request_mem_region(res->start, resource_size(res), "wd33c93"))
 201                 return -EBUSY;
 202
 203         instance = scsi_host_alloc(&amiga_a3000_scsi_template,
 204                                    sizeof(struct a3000_hostdata));
 205         if (!instance) {
 206                 error = -ENOMEM;
 207                 goto fail_alloc;
 208         }
 209
 210         instance->irq = IRQ_AMIGA_PORTS;
 211
 212         regs = ZTWO_VADDR(res->start);
 213         regs->DAWR = DAWR_A3000;
 214
 215         wdregs.SASR = &regs->SASR;
 216         wdregs.SCMD = &regs->SCMD;
 217
 218         hdata = shost_priv(instance);
 219         hdata->wh.no_sync = 0xff;
 220         hdata->wh.fast = 0;
 221         hdata->wh.dma_mode = CTRL_DMA;
 222         hdata->regs = regs;
 223
 224         wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_12_15);
 225         error = request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED,
 226                             "A3000 SCSI", instance);
 227         if (error)
 228                 goto fail_irq;
 229
 230         regs->CNTR = CNTR_PDMD | CNTR_INTEN;
 231
 232         error = scsi_add_host(instance, NULL);
 233         if (error)
 234                 goto fail_host;
 235
 236         platform_set_drvdata(pdev, instance);
 237
 238         scsi_scan_host(instance);
 239         return 0;
 240
 241 fail_host:
 242         free_irq(IRQ_AMIGA_PORTS, instance);
 243 fail_irq:
 244         scsi_host_put(instance);
 245 fail_alloc:
 246         release_mem_region(res->start, resource_size(res));
 247         return error;
 248 }
 249
 250 static int __exit amiga_a3000_scsi_remove(struct platform_device *pdev)
 251 {
 252         struct Scsi_Host *instance = platform_get_drvdata(pdev);
 253         struct a3000_hostdata *hdata = shost_priv(instance);
 254         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 255
 256         hdata->regs->CNTR = 0;
 257         scsi_remove_host(instance);
 258         free_irq(IRQ_AMIGA_PORTS, instance);
 259         scsi_host_put(instance);
 260         release_mem_region(res->start, resource_size(res));
 261         return 0;
 262 }
 263
 264 static struct platform_driver amiga_a3000_scsi_driver = {
 265         .remove = __exit_p(amiga_a3000_scsi_remove),
 266         .driver   = {
 267                 .name   = "amiga-a3000-scsi",
 268         },
 269 };
 270
 271 module_platform_driver_probe(amiga_a3000_scsi_driver, amiga_a3000_scsi_probe);
 272
 273 MODULE_DESCRIPTION("Amiga 3000 built-in SCSI");
 274 MODULE_LICENSE("GPL");
 275 MODULE_ALIAS("platform:amiga-a3000-scsi");