drivers/scsi/jazz_esp.c

   1 /* jazz_esp.c: ESP front-end for MIPS JAZZ systems.
   2  *
   3  * Copyright (C) 2007 Thomas Bogendörfer (tsbogend@alpha.frankende)
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/gfp.h>
   8 #include <linux/types.h>
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/dma-mapping.h>
  14
  15 #include <asm/irq.h>
  16 #include <asm/io.h>
  17 #include <asm/dma.h>
  18
  19 #include <asm/jazz.h>
  20 #include <asm/jazzdma.h>
  21
  22 #include <scsi/scsi_host.h>
  23
  24 #include "esp_scsi.h"
  25
  26 #define DRV_MODULE_NAME         "jazz_esp"
  27 #define PFX DRV_MODULE_NAME     ": "
  28 #define DRV_VERSION             "1.000"
  29 #define DRV_MODULE_RELDATE      "May 19, 2007"
  30
  31 static void jazz_esp_write8(struct esp *esp, u8 val, unsigned long reg)
  32 {
  33         *(volatile u8 *)(esp->regs + reg) = val;
  34 }
  35
  36 static u8 jazz_esp_read8(struct esp *esp, unsigned long reg)
  37 {
  38         return *(volatile u8 *)(esp->regs + reg);
  39 }
  40
  41 static int jazz_esp_irq_pending(struct esp *esp)
  42 {
  43         if (jazz_esp_read8(esp, ESP_STATUS) & ESP_STAT_INTR)
  44                 return 1;
  45         return 0;
  46 }
  47
  48 static void jazz_esp_reset_dma(struct esp *esp)
  49 {
  50         vdma_disable ((int)esp->dma_regs);
  51 }
  52
  53 static void jazz_esp_dma_drain(struct esp *esp)
  54 {
  55         /* nothing to do */
  56 }
  57
  58 static void jazz_esp_dma_invalidate(struct esp *esp)
  59 {
  60         vdma_disable ((int)esp->dma_regs);
  61 }
  62
  63 static void jazz_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
  64                                   u32 dma_count, int write, u8 cmd)
  65 {
  66         BUG_ON(!(cmd & ESP_CMD_DMA));
  67
  68         jazz_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
  69         jazz_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
  70         vdma_disable ((int)esp->dma_regs);
  71         if (write)
  72                 vdma_set_mode ((int)esp->dma_regs, DMA_MODE_READ);
  73         else
  74                 vdma_set_mode ((int)esp->dma_regs, DMA_MODE_WRITE);
  75
  76         vdma_set_addr ((int)esp->dma_regs, addr);
  77         vdma_set_count ((int)esp->dma_regs, dma_count);
  78         vdma_enable ((int)esp->dma_regs);
  79
  80         scsi_esp_cmd(esp, cmd);
  81 }
  82
  83 static int jazz_esp_dma_error(struct esp *esp)
  84 {
  85         u32 enable = vdma_get_enable((int)esp->dma_regs);
  86
  87         if (enable & (R4030_MEM_INTR|R4030_ADDR_INTR))
  88                 return 1;
  89
  90         return 0;
  91 }
  92
  93 static const struct esp_driver_ops jazz_esp_ops = {
  94         .esp_write8     =       jazz_esp_write8,
  95         .esp_read8      =       jazz_esp_read8,
  96         .irq_pending    =       jazz_esp_irq_pending,
  97         .reset_dma      =       jazz_esp_reset_dma,
  98         .dma_drain      =       jazz_esp_dma_drain,
  99         .dma_invalidate =       jazz_esp_dma_invalidate,
 100         .send_dma_cmd   =       jazz_esp_send_dma_cmd,
 101         .dma_error      =       jazz_esp_dma_error,
 102 };
 103
 104 static int esp_jazz_probe(struct platform_device *dev)
 105 {
 106         struct scsi_host_template *tpnt = &scsi_esp_template;
 107         struct Scsi_Host *host;
 108         struct esp *esp;
 109         struct resource *res;
 110         int err;
 111
 112         host = scsi_host_alloc(tpnt, sizeof(struct esp));
 113
 114         err = -ENOMEM;
 115         if (!host)
 116                 goto fail;
 117
 118         host->max_id = 8;
 119         esp = shost_priv(host);
 120
 121         esp->host = host;
 122         esp->dev = &dev->dev;
 123         esp->ops = &jazz_esp_ops;
 124
 125         res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 126         if (!res)
 127                 goto fail_unlink;
 128
 129         esp->regs = (void __iomem *)res->start;
 130         if (!esp->regs)
 131                 goto fail_unlink;
 132
 133         res = platform_get_resource(dev, IORESOURCE_MEM, 1);
 134         if (!res)
 135                 goto fail_unlink;
 136
 137         esp->dma_regs = (void __iomem *)res->start;
 138
 139         esp->command_block = dma_alloc_coherent(esp->dev, 16,
 140                                                 &esp->command_block_dma,
 141                                                 GFP_KERNEL);
 142         if (!esp->command_block)
 143                 goto fail_unmap_regs;
 144
 145         host->irq = platform_get_irq(dev, 0);
 146         err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
 147         if (err < 0)
 148                 goto fail_unmap_command_block;
 149
 150         esp->scsi_id = 7;
 151         esp->host->this_id = esp->scsi_id;
 152         esp->scsi_id_mask = (1 << esp->scsi_id);
 153         esp->cfreq = 40000000;
 154
 155         dev_set_drvdata(&dev->dev, esp);
 156
 157         err = scsi_esp_register(esp);
 158         if (err)
 159                 goto fail_free_irq;
 160
 161         return 0;
 162
 163 fail_free_irq:
 164         free_irq(host->irq, esp);
 165 fail_unmap_command_block:
 166         dma_free_coherent(esp->dev, 16,
 167                           esp->command_block,
 168                           esp->command_block_dma);
 169 fail_unmap_regs:
 170 fail_unlink:
 171         scsi_host_put(host);
 172 fail:
 173         return err;
 174 }
 175
 176 static int esp_jazz_remove(struct platform_device *dev)
 177 {
 178         struct esp *esp = dev_get_drvdata(&dev->dev);
 179         unsigned int irq = esp->host->irq;
 180
 181         scsi_esp_unregister(esp);
 182
 183         free_irq(irq, esp);
 184         dma_free_coherent(esp->dev, 16,
 185                           esp->command_block,
 186                           esp->command_block_dma);
 187
 188         scsi_host_put(esp->host);
 189
 190         return 0;
 191 }
 192
 193 /* work with hotplug and coldplug */
 194 MODULE_ALIAS("platform:jazz_esp");
 195
 196 static struct platform_driver esp_jazz_driver = {
 197         .probe          = esp_jazz_probe,
 198         .remove         = esp_jazz_remove,
 199         .driver = {
 200                 .name   = "jazz_esp",
 201         },
 202 };
 203
 204 static int __init jazz_esp_init(void)
 205 {
 206         return platform_driver_register(&esp_jazz_driver);
 207 }
 208
 209 static void __exit jazz_esp_exit(void)
 210 {
 211         platform_driver_unregister(&esp_jazz_driver);
 212 }
 213
 214 MODULE_DESCRIPTION("JAZZ ESP SCSI driver");
 215 MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)");
 216 MODULE_LICENSE("GPL");
 217 MODULE_VERSION(DRV_VERSION);
 218
 219 module_init(jazz_esp_init);
 220 module_exit(jazz_esp_exit);