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/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
  26struct 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
  32static 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
  58struct csr_space {
  59        u64     base;
  60        u64     length;
  61};
  62
  63static 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.address_length &&
  73            addr.producer_consumer == ACPI_CONSUMER) {
  74                space->base = addr.address.minimum;
  75                space->length = addr.address.address_length;
  76                return AE_CTRL_TERMINATE;
  77        }
  78        return AE_OK;           /* keep looking */
  79}
  80
  81static 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
  94acpi_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}
 104EXPORT_SYMBOL(hp_acpi_csr_space);
 105