arch/ia64/kernel/acpi-ext.c

   1 /*
   2  * (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
   3  *      Alex Williamson <alex.williamson@hp.com>
   4  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/acpi.h>
  14
  15 #include <asm/acpi-ext.h>
  16
  17 /*
  18  * Device CSRs that do not appear in PCI config space should be described
  19  * via ACPI.  This would normally be done with Address Space Descriptors
  20  * marked as "consumer-only," but old versions of Windows and Linux ignore
  21  * the producer/consumer flag, so HP invented a vendor-defined resource to
  22  * describe the location and size of CSR space.
  23  */
  24
  25 struct acpi_vendor_uuid hp_ccsr_uuid = {
  26         .subtype = 2,
  27         .data = { 0xf9, 0xad, 0xe9, 0x69, 0x4f, 0x92, 0x5f, 0xab, 0xf6, 0x4a,
  28             0x24, 0xd2, 0x01, 0x37, 0x0e, 0xad },
  29 };
  30
  31 static acpi_status hp_ccsr_locate(acpi_handle obj, u64 *base, u64 *length)
  32 {
  33         acpi_status status;
  34         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  35         struct acpi_resource *resource;
  36         struct acpi_resource_vendor_typed *vendor;
  37
  38         status = acpi_get_vendor_resource(obj, METHOD_NAME__CRS, &hp_ccsr_uuid,
  39                 &buffer);
  40
  41         resource = buffer.pointer;
  42         vendor = &resource->data.vendor_typed;
  43
  44         if (ACPI_FAILURE(status) || vendor->byte_length < 16) {
  45                 status = AE_NOT_FOUND;
  46                 goto exit;
  47         }
  48
  49         memcpy(base, vendor->byte_data, sizeof(*base));
  50         memcpy(length, vendor->byte_data + 8, sizeof(*length));
  51
  52   exit:
  53         kfree(buffer.pointer);
  54         return status;
  55 }
  56
  57 struct csr_space {
  58         u64     base;
  59         u64     length;
  60 };
  61
  62 static acpi_status find_csr_space(struct acpi_resource *resource, void *data)
  63 {
  64         struct csr_space *space = data;
  65         struct acpi_resource_address64 addr;
  66         acpi_status status;
  67
  68         status = acpi_resource_to_address64(resource, &addr);
  69         if (ACPI_SUCCESS(status) &&
  70             addr.resource_type == ACPI_MEMORY_RANGE &&
  71             addr.address_length &&
  72             addr.producer_consumer == ACPI_CONSUMER) {
  73                 space->base = addr.minimum;
  74                 space->length = addr.address_length;
  75                 return AE_CTRL_TERMINATE;
  76         }
  77         return AE_OK;           /* keep looking */
  78 }
  79
  80 static acpi_status hp_crs_locate(acpi_handle obj, u64 *base, u64 *length)
  81 {
  82         struct csr_space space = { 0, 0 };
  83
  84         acpi_walk_resources(obj, METHOD_NAME__CRS, find_csr_space, &space);
  85         if (!space.length)
  86                 return AE_NOT_FOUND;
  87
  88         *base = space.base;
  89         *length = space.length;
  90         return AE_OK;
  91 }
  92
  93 acpi_status hp_acpi_csr_space(acpi_handle obj, u64 *csr_base, u64 *csr_length)
  94 {
  95         acpi_status status;
  96
  97         status = hp_ccsr_locate(obj, csr_base, csr_length);
  98         if (ACPI_SUCCESS(status))
  99                 return status;
 100
 101         return hp_crs_locate(obj, csr_base, csr_length);
 102 }
 103 EXPORT_SYMBOL(hp_acpi_csr_space);