/*

   * (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
   *	Alex Williamson <alex.williamson@hp.com>
   *	Bjorn Helgaas <bjorn.helgaas@hp.com>

   *

   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.

   */

  #include <linux/module.h>
  #include <linux/types.h>

  #include <linux/slab.h>

  #include <linux/acpi.h>

  
  #include <asm/acpi-ext.h>

  /*
   * Device CSRs that do not appear in PCI config space should be described
   * via ACPI.  This would normally be done with Address Space Descriptors
   * marked as "consumer-only," but old versions of Windows and Linux ignore
   * the producer/consumer flag, so HP invented a vendor-defined resource to
   * describe the location and size of CSR space.
   */

  struct acpi_vendor_uuid hp_ccsr_uuid = {
  	.subtype = 2,
  	.data = { 0xf9, 0xad, 0xe9, 0x69, 0x4f, 0x92, 0x5f, 0xab, 0xf6, 0x4a,
  	    0x24, 0xd2, 0x01, 0x37, 0x0e, 0xad },

  };

  static acpi_status hp_ccsr_locate(acpi_handle obj, u64 *base, u64 *length)

  {

  	acpi_status status;
  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  	struct acpi_resource *resource;
  	struct acpi_resource_vendor_typed *vendor;

  	status = acpi_get_vendor_resource(obj, METHOD_NAME__CRS, &hp_ccsr_uuid,
  		&buffer);

  	resource = buffer.pointer;
  	vendor = &resource->data.vendor_typed;

  	if (ACPI_FAILURE(status) || vendor->byte_length < 16) {
  		status = AE_NOT_FOUND;
  		goto exit;
  	}

  	memcpy(base, vendor->byte_data, sizeof(*base));
  	memcpy(length, vendor->byte_data + 8, sizeof(*length));
  
    exit:

  	kfree(buffer.pointer);

  	return status;

  }

  struct csr_space {
  	u64	base;
  	u64	length;

  };

  static acpi_status find_csr_space(struct acpi_resource *resource, void *data)

  {

  	struct csr_space *space = data;
  	struct acpi_resource_address64 addr;

  	acpi_status status;

  	status = acpi_resource_to_address64(resource, &addr);
  	if (ACPI_SUCCESS(status) &&
  	    addr.resource_type == ACPI_MEMORY_RANGE &&
  	    addr.address_length &&
  	    addr.producer_consumer == ACPI_CONSUMER) {
  		space->base = addr.minimum;
  		space->length = addr.address_length;
  		return AE_CTRL_TERMINATE;
  	}
  	return AE_OK;		/* keep looking */
  }

  static acpi_status hp_crs_locate(acpi_handle obj, u64 *base, u64 *length)
  {
  	struct csr_space space = { 0, 0 };

  	acpi_walk_resources(obj, METHOD_NAME__CRS, find_csr_space, &space);
  	if (!space.length)
  		return AE_NOT_FOUND;

  	*base = space.base;
  	*length = space.length;

  	return AE_OK;
  }

  acpi_status hp_acpi_csr_space(acpi_handle obj, u64 *csr_base, u64 *csr_length)
  {
  	acpi_status status;
  
  	status = hp_ccsr_locate(obj, csr_base, csr_length);
  	if (ACPI_SUCCESS(status))
  		return status;
  
  	return hp_crs_locate(obj, csr_base, csr_length);
  }

  EXPORT_SYMBOL(hp_acpi_csr_space);