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 dma_addr_t jazz_esp_map_single(struct esp *esp, void *buf,
  42                                       size_t sz, int dir)
  43 {
  44         return dma_map_single(esp->dev, buf, sz, dir);
  45 }
  46
  47 static int jazz_esp_map_sg(struct esp *esp, struct scatterlist *sg,
  48                                   int num_sg, int dir)
  49 {
  50         return dma_map_sg(esp->dev, sg, num_sg, dir);
  51 }
  52
  53 static void jazz_esp_unmap_single(struct esp *esp, dma_addr_t addr,
  54                                   size_t sz, int dir)
  55 {
  56         dma_unmap_single(esp->dev, addr, sz, dir);
  57 }
  58
  59 static void jazz_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
  60                               int num_sg, int dir)
  61 {
  62         dma_unmap_sg(esp->dev, sg, num_sg, dir);
  63 }
  64
  65 static int jazz_esp_irq_pending(struct esp *esp)
  66 {
  67         if (jazz_esp_read8(esp, ESP_STATUS) & ESP_STAT_INTR)
  68                 return 1;
  69         return 0;
  70 }
  71
  72 static void jazz_esp_reset_dma(struct esp *esp)
  73 {
  74         vdma_disable ((int)esp->dma_regs);
  75 }
  76
  77 static void jazz_esp_dma_drain(struct esp *esp)
  78 {
  79         /* nothing to do */
  80 }
  81
  82 static void jazz_esp_dma_invalidate(struct esp *esp)
  83 {
  84         vdma_disable ((int)esp->dma_regs);
  85 }
  86
  87 static void jazz_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
  88                                   u32 dma_count, int write, u8 cmd)
  89 {
  90         BUG_ON(!(cmd & ESP_CMD_DMA));
  91
  92         jazz_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
  93         jazz_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
  94         vdma_disable ((int)esp->dma_regs);
  95         if (write)
  96                 vdma_set_mode ((int)esp->dma_regs, DMA_MODE_READ);
  97         else
  98                 vdma_set_mode ((int)esp->dma_regs, DMA_MODE_WRITE);
  99
 100         vdma_set_addr ((int)esp->dma_regs, addr);
 101         vdma_set_count ((int)esp->dma_regs, dma_count);
 102         vdma_enable ((int)esp->dma_regs);
 103
 104         scsi_esp_cmd(esp, cmd);
 105 }
 106
 107 static int jazz_esp_dma_error(struct esp *esp)
 108 {
 109         u32 enable = vdma_get_enable((int)esp->dma_regs);
 110
 111         if (enable & (R4030_MEM_INTR|R4030_ADDR_INTR))
 112                 return 1;
 113
 114         return 0;
 115 }
 116
 117 static const struct esp_driver_ops jazz_esp_ops = {
 118         .esp_write8     =       jazz_esp_write8,
 119         .esp_read8      =       jazz_esp_read8,
 120         .map_single     =       jazz_esp_map_single,
 121         .map_sg         =       jazz_esp_map_sg,
 122         .unmap_single   =       jazz_esp_unmap_single,
 123         .unmap_sg       =       jazz_esp_unmap_sg,
 124         .irq_pending    =       jazz_esp_irq_pending,
 125         .reset_dma      =       jazz_esp_reset_dma,
 126         .dma_drain      =       jazz_esp_dma_drain,
 127         .dma_invalidate =       jazz_esp_dma_invalidate,
 128         .send_dma_cmd   =       jazz_esp_send_dma_cmd,
 129         .dma_error      =       jazz_esp_dma_error,
 130 };
 131
 132 static int esp_jazz_probe(struct platform_device *dev)
 133 {
 134         struct scsi_host_template *tpnt = &scsi_esp_template;
 135         struct Scsi_Host *host;
 136         struct esp *esp;
 137         struct resource *res;
 138         int err;
 139
 140         host = scsi_host_alloc(tpnt, sizeof(struct esp));
 141
 142         err = -ENOMEM;
 143         if (!host)
 144                 goto fail;
 145
 146         host->max_id = 8;
 147         esp = shost_priv(host);
 148
 149         esp->host = host;
 150         esp->dev = dev;
 151         esp->ops = &jazz_esp_ops;
 152
 153         res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 154         if (!res)
 155                 goto fail_unlink;
 156
 157         esp->regs = (void __iomem *)res->start;
 158         if (!esp->regs)
 159                 goto fail_unlink;
 160
 161         res = platform_get_resource(dev, IORESOURCE_MEM, 1);
 162         if (!res)
 163                 goto fail_unlink;
 164
 165         esp->dma_regs = (void __iomem *)res->start;
 166
 167         esp->command_block = dma_alloc_coherent(esp->dev, 16,
 168                                                 &esp->command_block_dma,
 169                                                 GFP_KERNEL);
 170         if (!esp->command_block)
 171                 goto fail_unmap_regs;
 172
 173         host->irq = platform_get_irq(dev, 0);
 174         err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
 175         if (err < 0)
 176                 goto fail_unmap_command_block;
 177
 178         esp->scsi_id = 7;
 179         esp->host->this_id = esp->scsi_id;
 180         esp->scsi_id_mask = (1 << esp->scsi_id);
 181         esp->cfreq = 40000000;
 182
 183         dev_set_drvdata(&dev->dev, esp);
 184
 185         err = scsi_esp_register(esp, &dev->dev);
 186         if (err)
 187                 goto fail_free_irq;
 188
 189         return 0;
 190
 191 fail_free_irq:
 192         free_irq(host->irq, esp);
 193 fail_unmap_command_block:
 194         dma_free_coherent(esp->dev, 16,
 195                           esp->command_block,
 196                           esp->command_block_dma);
 197 fail_unmap_regs:
 198 fail_unlink:
 199         scsi_host_put(host);
 200 fail:
 201         return err;
 202 }
 203
 204 static int esp_jazz_remove(struct platform_device *dev)
 205 {
 206         struct esp *esp = dev_get_drvdata(&dev->dev);
 207         unsigned int irq = esp->host->irq;
 208
 209         scsi_esp_unregister(esp);
 210
 211         free_irq(irq, esp);
 212         dma_free_coherent(esp->dev, 16,
 213                           esp->command_block,
 214                           esp->command_block_dma);
 215
 216         scsi_host_put(esp->host);
 217
 218         return 0;
 219 }
 220
 221 /* work with hotplug and coldplug */
 222 MODULE_ALIAS("platform:jazz_esp");
 223
 224 static struct platform_driver esp_jazz_driver = {
 225         .probe          = esp_jazz_probe,
 226         .remove         = esp_jazz_remove,
 227         .driver = {
 228                 .name   = "jazz_esp",
 229         },
 230 };
 231
 232 static int __init jazz_esp_init(void)
 233 {
 234         return platform_driver_register(&esp_jazz_driver);
 235 }
 236
 237 static void __exit jazz_esp_exit(void)
 238 {
 239         platform_driver_unregister(&esp_jazz_driver);
 240 }
 241
 242 MODULE_DESCRIPTION("JAZZ ESP SCSI driver");
 243 MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)");
 244 MODULE_LICENSE("GPL");
 245 MODULE_VERSION(DRV_VERSION);
 246
 247 module_init(jazz_esp_init);
 248 module_exit(jazz_esp_exit);