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