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