LXR linux/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
  25struct 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
  31static 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
  57struct csr_space {
  58        u64     base;
  59        u64     length;
  60};
  61
  62static 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
  80static 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
  93acpi_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}
 103EXPORT_SYMBOL(hp_acpi_csr_space);
 104