/* jazz_esp.c: ESP front-end for MIPS JAZZ systems.

   *

   * Copyright (C) 2007 Thomas Bogendörfer (tsbogend@alpha.frankende)

   */

  #include <linux/kernel.h>

  #include <linux/gfp.h>

  #include <linux/types.h>

  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/platform_device.h>
  #include <linux/dma-mapping.h>

  
  #include <asm/irq.h>

  #include <asm/io.h>
  #include <asm/dma.h>

  #include <asm/jazz.h>
  #include <asm/jazzdma.h>

  #include <scsi/scsi_host.h>

  #include "esp_scsi.h"

  #define DRV_MODULE_NAME		"jazz_esp"
  #define PFX DRV_MODULE_NAME	": "
  #define DRV_VERSION		"1.000"
  #define DRV_MODULE_RELDATE	"May 19, 2007"

  static void jazz_esp_write8(struct esp *esp, u8 val, unsigned long reg)

  {

  	*(volatile u8 *)(esp->regs + reg) = val;

  }

  static u8 jazz_esp_read8(struct esp *esp, unsigned long reg)

  {

  	return *(volatile u8 *)(esp->regs + reg);

  }

  static dma_addr_t jazz_esp_map_single(struct esp *esp, void *buf,
  				      size_t sz, int dir)

  {

  	return dma_map_single(esp->dev, buf, sz, dir);

  }

  static int jazz_esp_map_sg(struct esp *esp, struct scatterlist *sg,
  				  int num_sg, int dir)

  {

  	return dma_map_sg(esp->dev, sg, num_sg, dir);

  }

  static void jazz_esp_unmap_single(struct esp *esp, dma_addr_t addr,
  				  size_t sz, int dir)

  {

  	dma_unmap_single(esp->dev, addr, sz, dir);

  }

  static void jazz_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
  			      int num_sg, int dir)

  {

  	dma_unmap_sg(esp->dev, sg, num_sg, dir);

  }

  static int jazz_esp_irq_pending(struct esp *esp)

  {

  	if (jazz_esp_read8(esp, ESP_STATUS) & ESP_STAT_INTR)
  		return 1;
  	return 0;

  }

  static void jazz_esp_reset_dma(struct esp *esp)

  {

  	vdma_disable ((int)esp->dma_regs);

  }

  static void jazz_esp_dma_drain(struct esp *esp)

  {

  	/* nothing to do */

  }

  static void jazz_esp_dma_invalidate(struct esp *esp)

  {

  	vdma_disable ((int)esp->dma_regs);

  }

  static void jazz_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
  				  u32 dma_count, int write, u8 cmd)

  {

  	BUG_ON(!(cmd & ESP_CMD_DMA));
  
  	jazz_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
  	jazz_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
  	vdma_disable ((int)esp->dma_regs);
  	if (write)
  		vdma_set_mode ((int)esp->dma_regs, DMA_MODE_READ);
  	else
  		vdma_set_mode ((int)esp->dma_regs, DMA_MODE_WRITE);
  
  	vdma_set_addr ((int)esp->dma_regs, addr);
  	vdma_set_count ((int)esp->dma_regs, dma_count);
  	vdma_enable ((int)esp->dma_regs);
  
  	scsi_esp_cmd(esp, cmd);

  }

  static int jazz_esp_dma_error(struct esp *esp)

  {

  	u32 enable = vdma_get_enable((int)esp->dma_regs);
  
  	if (enable & (R4030_MEM_INTR|R4030_ADDR_INTR))
  		return 1;
  
  	return 0;

  }

  static const struct esp_driver_ops jazz_esp_ops = {
  	.esp_write8	=	jazz_esp_write8,
  	.esp_read8	=	jazz_esp_read8,
  	.map_single	=	jazz_esp_map_single,
  	.map_sg		=	jazz_esp_map_sg,
  	.unmap_single	=	jazz_esp_unmap_single,
  	.unmap_sg	=	jazz_esp_unmap_sg,
  	.irq_pending	=	jazz_esp_irq_pending,
  	.reset_dma	=	jazz_esp_reset_dma,
  	.dma_drain	=	jazz_esp_dma_drain,
  	.dma_invalidate	=	jazz_esp_dma_invalidate,
  	.send_dma_cmd	=	jazz_esp_send_dma_cmd,
  	.dma_error	=	jazz_esp_dma_error,
  };
  
  static int __devinit esp_jazz_probe(struct platform_device *dev)

  {

  	struct scsi_host_template *tpnt = &scsi_esp_template;
  	struct Scsi_Host *host;
  	struct esp *esp;
  	struct resource *res;
  	int err;
  
  	host = scsi_host_alloc(tpnt, sizeof(struct esp));
  
  	err = -ENOMEM;
  	if (!host)
  		goto fail;
  
  	host->max_id = 8;

  	esp = shost_priv(host);

  
  	esp->host = host;
  	esp->dev = dev;
  	esp->ops = &jazz_esp_ops;
  
  	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
  	if (!res)
  		goto fail_unlink;
  
  	esp->regs = (void __iomem *)res->start;
  	if (!esp->regs)
  		goto fail_unlink;
  
  	res = platform_get_resource(dev, IORESOURCE_MEM, 1);
  	if (!res)
  		goto fail_unlink;
  
  	esp->dma_regs = (void __iomem *)res->start;
  
  	esp->command_block = dma_alloc_coherent(esp->dev, 16,
  						&esp->command_block_dma,
  						GFP_KERNEL);
  	if (!esp->command_block)
  		goto fail_unmap_regs;
  
  	host->irq = platform_get_irq(dev, 0);
  	err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
  	if (err < 0)
  		goto fail_unmap_command_block;
  
  	esp->scsi_id = 7;
  	esp->host->this_id = esp->scsi_id;
  	esp->scsi_id_mask = (1 << esp->scsi_id);
  	esp->cfreq = 40000000;
  
  	dev_set_drvdata(&dev->dev, esp);
  
  	err = scsi_esp_register(esp, &dev->dev);
  	if (err)
  		goto fail_free_irq;
  
  	return 0;
  
  fail_free_irq:
  	free_irq(host->irq, esp);
  fail_unmap_command_block:
  	dma_free_coherent(esp->dev, 16,
  			  esp->command_block,
  			  esp->command_block_dma);
  fail_unmap_regs:
  fail_unlink:
  	scsi_host_put(host);
  fail:
  	return err;

  }

  static int __devexit esp_jazz_remove(struct platform_device *dev)

  {

  	struct esp *esp = dev_get_drvdata(&dev->dev);
  	unsigned int irq = esp->host->irq;
  
  	scsi_esp_unregister(esp);
  
  	free_irq(irq, esp);
  	dma_free_coherent(esp->dev, 16,
  			  esp->command_block,
  			  esp->command_block_dma);
  
  	scsi_host_put(esp->host);
  
  	return 0;

  }

  /* work with hotplug and coldplug */
  MODULE_ALIAS("platform:jazz_esp");

  static struct platform_driver esp_jazz_driver = {
  	.probe		= esp_jazz_probe,
  	.remove		= __devexit_p(esp_jazz_remove),
  	.driver	= {
  		.name	= "jazz_esp",

  		.owner	= THIS_MODULE,

  	},
  };

  static int __init jazz_esp_init(void)

  {

  	return platform_driver_register(&esp_jazz_driver);

  }

  static void __exit jazz_esp_exit(void)
  {
  	platform_driver_unregister(&esp_jazz_driver);

  }

  MODULE_DESCRIPTION("JAZZ ESP SCSI driver");
  MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)");
  MODULE_LICENSE("GPL");
  MODULE_VERSION(DRV_VERSION);
  
  module_init(jazz_esp_init);
  module_exit(jazz_esp_exit);