/*
   * PS3 Storage Library
   *
   * Copyright (C) 2007 Sony Computer Entertainment Inc.
   * Copyright 2007 Sony Corp.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License as published
   * by the Free Software Foundation; version 2 of the License.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License along
   * with this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
   */
  
  #include <linux/dma-mapping.h>

  #include <linux/module.h>

  
  #include <asm/lv1call.h>
  #include <asm/ps3stor.h>

  /*
   * A workaround for flash memory I/O errors when the internal hard disk
   * has not been formatted for OtherOS use.  Delay disk close until flash
   * memory is closed.
   */
  
  static struct ps3_flash_workaround {
  	int flash_open;
  	int disk_open;
  	struct ps3_system_bus_device *disk_sbd;
  } ps3_flash_workaround;
  
  static int ps3stor_open_hv_device(struct ps3_system_bus_device *sbd)
  {
  	int error = ps3_open_hv_device(sbd);
  
  	if (error)
  		return error;
  
  	if (sbd->match_id == PS3_MATCH_ID_STOR_FLASH)
  		ps3_flash_workaround.flash_open = 1;
  
  	if (sbd->match_id == PS3_MATCH_ID_STOR_DISK)
  		ps3_flash_workaround.disk_open = 1;
  
  	return 0;
  }
  
  static int ps3stor_close_hv_device(struct ps3_system_bus_device *sbd)
  {
  	int error;
  
  	if (sbd->match_id == PS3_MATCH_ID_STOR_DISK
  		&& ps3_flash_workaround.disk_open
  		&& ps3_flash_workaround.flash_open) {
  		ps3_flash_workaround.disk_sbd = sbd;
  		return 0;
  	}
  
  	error = ps3_close_hv_device(sbd);
  
  	if (error)
  		return error;
  
  	if (sbd->match_id == PS3_MATCH_ID_STOR_DISK)
  		ps3_flash_workaround.disk_open = 0;
  
  	if (sbd->match_id == PS3_MATCH_ID_STOR_FLASH) {
  		ps3_flash_workaround.flash_open = 0;
  
  		if (ps3_flash_workaround.disk_sbd) {
  			ps3_close_hv_device(ps3_flash_workaround.disk_sbd);
  			ps3_flash_workaround.disk_open = 0;
  			ps3_flash_workaround.disk_sbd = NULL;
  		}
  	}
  
  	return 0;
  }

  
  static int ps3stor_probe_access(struct ps3_storage_device *dev)
  {
  	int res, error;
  	unsigned int i;
  	unsigned long n;
  
  	if (dev->sbd.match_id == PS3_MATCH_ID_STOR_ROM) {
  		/* special case: CD-ROM is assumed always accessible */
  		dev->accessible_regions = 1;
  		return 0;
  	}
  
  	error = -EPERM;
  	for (i = 0; i < dev->num_regions; i++) {
  		dev_dbg(&dev->sbd.core,
  			"%s:%u: checking accessibility of region %u
  ",
  			__func__, __LINE__, i);
  
  		dev->region_idx = i;
  		res = ps3stor_read_write_sectors(dev, dev->bounce_lpar, 0, 1,
  						 0);
  		if (res) {
  			dev_dbg(&dev->sbd.core, "%s:%u: read failed, "
  				"region %u is not accessible
  ", __func__,
  				__LINE__, i);
  			continue;
  		}
  
  		dev_dbg(&dev->sbd.core, "%s:%u: region %u is accessible
  ",
  			__func__, __LINE__, i);
  		set_bit(i, &dev->accessible_regions);
  
  		/* We can access at least one region */
  		error = 0;
  	}
  	if (error)
  		return error;
  
  	n = hweight_long(dev->accessible_regions);
  	if (n > 1)
  		dev_info(&dev->sbd.core,
  			 "%s:%u: %lu accessible regions found. Only the first "

  			 "one will be used
  ",

  			 __func__, __LINE__, n);
  	dev->region_idx = __ffs(dev->accessible_regions);
  	dev_info(&dev->sbd.core,

  		 "First accessible region has index %u start %llu size %llu
  ",

  		 dev->region_idx, dev->regions[dev->region_idx].start,
  		 dev->regions[dev->region_idx].size);
  
  	return 0;
  }
  
  
  /**
   *	ps3stor_setup - Setup a storage device before use
   *	@dev: Pointer to a struct ps3_storage_device
   *	@handler: Pointer to an interrupt handler
   *
   *	Returns 0 for success, or an error code
   */
  int ps3stor_setup(struct ps3_storage_device *dev, irq_handler_t handler)
  {
  	int error, res, alignment;
  	enum ps3_dma_page_size page_size;

  	error = ps3stor_open_hv_device(&dev->sbd);

  	if (error) {
  		dev_err(&dev->sbd.core,
  			"%s:%u: ps3_open_hv_device failed %d
  ", __func__,
  			__LINE__, error);
  		goto fail;
  	}
  
  	error = ps3_sb_event_receive_port_setup(&dev->sbd, PS3_BINDING_CPU_ANY,
  						&dev->irq);
  	if (error) {
  		dev_err(&dev->sbd.core,
  			"%s:%u: ps3_sb_event_receive_port_setup failed %d
  ",
  		       __func__, __LINE__, error);
  		goto fail_close_device;
  	}

  	error = request_irq(dev->irq, handler, 0,

  			    dev->sbd.core.driver->name, dev);
  	if (error) {
  		dev_err(&dev->sbd.core, "%s:%u: request_irq failed %d
  ",
  			__func__, __LINE__, error);
  		goto fail_sb_event_receive_port_destroy;
  	}
  
  	alignment = min(__ffs(dev->bounce_size),
  			__ffs((unsigned long)dev->bounce_buf));
  	if (alignment < 12) {
  		dev_err(&dev->sbd.core,
  			"%s:%u: bounce buffer not aligned (%lx at 0x%p)
  ",
  			__func__, __LINE__, dev->bounce_size, dev->bounce_buf);
  		error = -EINVAL;
  		goto fail_free_irq;
  	} else if (alignment < 16)
  		page_size = PS3_DMA_4K;
  	else
  		page_size = PS3_DMA_64K;
  	dev->sbd.d_region = &dev->dma_region;
  	ps3_dma_region_init(&dev->sbd, &dev->dma_region, page_size,
  			    PS3_DMA_OTHER, dev->bounce_buf, dev->bounce_size);
  	res = ps3_dma_region_create(&dev->dma_region);
  	if (res) {
  		dev_err(&dev->sbd.core, "%s:%u: cannot create DMA region
  ",
  			__func__, __LINE__);
  		error = -ENOMEM;
  		goto fail_free_irq;
  	}
  
  	dev->bounce_lpar = ps3_mm_phys_to_lpar(__pa(dev->bounce_buf));
  	dev->bounce_dma = dma_map_single(&dev->sbd.core, dev->bounce_buf,
  					 dev->bounce_size, DMA_BIDIRECTIONAL);
  	if (!dev->bounce_dma) {
  		dev_err(&dev->sbd.core, "%s:%u: map DMA region failed
  ",
  			__func__, __LINE__);
  		error = -ENODEV;
  		goto fail_free_dma;
  	}
  
  	error = ps3stor_probe_access(dev);
  	if (error) {
  		dev_err(&dev->sbd.core, "%s:%u: No accessible regions found
  ",
  			__func__, __LINE__);
  		goto fail_unmap_dma;
  	}
  	return 0;
  
  fail_unmap_dma:
  	dma_unmap_single(&dev->sbd.core, dev->bounce_dma, dev->bounce_size,
  			 DMA_BIDIRECTIONAL);
  fail_free_dma:
  	ps3_dma_region_free(&dev->dma_region);
  fail_free_irq:
  	free_irq(dev->irq, dev);
  fail_sb_event_receive_port_destroy:
  	ps3_sb_event_receive_port_destroy(&dev->sbd, dev->irq);
  fail_close_device:

  	ps3stor_close_hv_device(&dev->sbd);

  fail:
  	return error;
  }
  EXPORT_SYMBOL_GPL(ps3stor_setup);
  
  
  /**
   *	ps3stor_teardown - Tear down a storage device after use
   *	@dev: Pointer to a struct ps3_storage_device
   */
  void ps3stor_teardown(struct ps3_storage_device *dev)
  {
  	int error;
  
  	dma_unmap_single(&dev->sbd.core, dev->bounce_dma, dev->bounce_size,
  			 DMA_BIDIRECTIONAL);
  	ps3_dma_region_free(&dev->dma_region);
  
  	free_irq(dev->irq, dev);
  
  	error = ps3_sb_event_receive_port_destroy(&dev->sbd, dev->irq);
  	if (error)
  		dev_err(&dev->sbd.core,
  			"%s:%u: destroy event receive port failed %d
  ",
  			__func__, __LINE__, error);

  	error = ps3stor_close_hv_device(&dev->sbd);

  	if (error)
  		dev_err(&dev->sbd.core,
  			"%s:%u: ps3_close_hv_device failed %d
  ", __func__,
  			__LINE__, error);
  }
  EXPORT_SYMBOL_GPL(ps3stor_teardown);
  
  
  /**
   *	ps3stor_read_write_sectors - read/write from/to a storage device
   *	@dev: Pointer to a struct ps3_storage_device
   *	@lpar: HV logical partition address
   *	@start_sector: First sector to read/write
   *	@sectors: Number of sectors to read/write
   *	@write: Flag indicating write (non-zero) or read (zero)
   *
   *	Returns 0 for success, -1 in case of failure to submit the command, or
   *	an LV1 status value in case of other errors
   */
  u64 ps3stor_read_write_sectors(struct ps3_storage_device *dev, u64 lpar,
  			       u64 start_sector, u64 sectors, int write)
  {
  	unsigned int region_id = dev->regions[dev->region_idx].id;
  	const char *op = write ? "write" : "read";
  	int res;

  	dev_dbg(&dev->sbd.core, "%s:%u: %s %llu sectors starting at %llu
  ",

  		__func__, __LINE__, op, sectors, start_sector);
  
  	init_completion(&dev->done);
  	res = write ? lv1_storage_write(dev->sbd.dev_id, region_id,
  					start_sector, sectors, 0, lpar,
  					&dev->tag)
  		    : lv1_storage_read(dev->sbd.dev_id, region_id,
  				       start_sector, sectors, 0, lpar,
  				       &dev->tag);
  	if (res) {
  		dev_dbg(&dev->sbd.core, "%s:%u: %s failed %d
  ", __func__,
  			__LINE__, op, res);
  		return -1;
  	}
  
  	wait_for_completion(&dev->done);
  	if (dev->lv1_status) {

  		dev_dbg(&dev->sbd.core, "%s:%u: %s failed 0x%llx
  ", __func__,

  			__LINE__, op, dev->lv1_status);
  		return dev->lv1_status;
  	}
  
  	dev_dbg(&dev->sbd.core, "%s:%u: %s completed
  ", __func__, __LINE__,
  		op);
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(ps3stor_read_write_sectors);
  
  
  /**
   *	ps3stor_send_command - send a device command to a storage device
   *	@dev: Pointer to a struct ps3_storage_device
   *	@cmd: Command number
   *	@arg1: First command argument
   *	@arg2: Second command argument
   *	@arg3: Third command argument
   *	@arg4: Fourth command argument
   *
   *	Returns 0 for success, -1 in case of failure to submit the command, or
   *	an LV1 status value in case of other errors
   */
  u64 ps3stor_send_command(struct ps3_storage_device *dev, u64 cmd, u64 arg1,
  			 u64 arg2, u64 arg3, u64 arg4)
  {
  	int res;

  	dev_dbg(&dev->sbd.core, "%s:%u: send device command 0x%llx
  ", __func__,

  		__LINE__, cmd);
  
  	init_completion(&dev->done);
  
  	res = lv1_storage_send_device_command(dev->sbd.dev_id, cmd, arg1,
  					      arg2, arg3, arg4, &dev->tag);
  	if (res) {
  		dev_err(&dev->sbd.core,

  			"%s:%u: send_device_command 0x%llx failed %d
  ",

  			__func__, __LINE__, cmd, res);
  		return -1;
  	}
  
  	wait_for_completion(&dev->done);
  	if (dev->lv1_status) {

  		dev_dbg(&dev->sbd.core, "%s:%u: command 0x%llx failed 0x%llx
  ",

  			__func__, __LINE__, cmd, dev->lv1_status);
  		return dev->lv1_status;
  	}

  	dev_dbg(&dev->sbd.core, "%s:%u: command 0x%llx completed
  ", __func__,

  		__LINE__, cmd);
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(ps3stor_send_command);
  
  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("PS3 Storage Bus Library");
  MODULE_AUTHOR("Sony Corporation");