LXR linux/arch/ia64/kernel/acpi-ext.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
   4 *      Alex Williamson <alex.williamson@hp.com>
   5 *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/types.h>
  10#include <linux/slab.h>
  11#include <linux/acpi.h>
  12
  13#include <asm/acpi-ext.h>
  14
  15/*
  16 * Device CSRs that do not appear in PCI config space should be described
  17 * via ACPI.  This would normally be done with Address Space Descriptors
  18 * marked as "consumer-only," but old versions of Windows and Linux ignore
  19 * the producer/consumer flag, so HP invented a vendor-defined resource to
  20 * describe the location and size of CSR space.
  21 */
  22
  23struct acpi_vendor_uuid hp_ccsr_uuid = {
  24        .subtype = 2,
  25        .data = { 0xf9, 0xad, 0xe9, 0x69, 0x4f, 0x92, 0x5f, 0xab, 0xf6, 0x4a,
  26            0x24, 0xd2, 0x01, 0x37, 0x0e, 0xad },
  27};
  28
  29static acpi_status hp_ccsr_locate(acpi_handle obj, u64 *base, u64 *length)
  30{
  31        acpi_status status;
  32        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  33        struct acpi_resource *resource;
  34        struct acpi_resource_vendor_typed *vendor;
  35
  36        status = acpi_get_vendor_resource(obj, METHOD_NAME__CRS, &hp_ccsr_uuid,
  37                &buffer);
  38
  39        resource = buffer.pointer;
  40        vendor = &resource->data.vendor_typed;
  41
  42        if (ACPI_FAILURE(status) || vendor->byte_length < 16) {
  43                status = AE_NOT_FOUND;
  44                goto exit;
  45        }
  46
  47        memcpy(base, vendor->byte_data, sizeof(*base));
  48        memcpy(length, vendor->byte_data + 8, sizeof(*length));
  49
  50  exit:
  51        kfree(buffer.pointer);
  52        return status;
  53}
  54
  55struct csr_space {
  56        u64     base;
  57        u64     length;
  58};
  59
  60static acpi_status find_csr_space(struct acpi_resource *resource, void *data)
  61{
  62        struct csr_space *space = data;
  63        struct acpi_resource_address64 addr;
  64        acpi_status status;
  65
  66        status = acpi_resource_to_address64(resource, &addr);
  67        if (ACPI_SUCCESS(status) &&
  68            addr.resource_type == ACPI_MEMORY_RANGE &&
  69            addr.address.address_length &&
  70            addr.producer_consumer == ACPI_CONSUMER) {
  71                space->base = addr.address.minimum;
  72                space->length = addr.address.address_length;
  73                return AE_CTRL_TERMINATE;
  74        }
  75        return AE_OK;           /* keep looking */
  76}
  77
  78static acpi_status hp_crs_locate(acpi_handle obj, u64 *base, u64 *length)
  79{
  80        struct csr_space space = { 0, 0 };
  81
  82        acpi_walk_resources(obj, METHOD_NAME__CRS, find_csr_space, &space);
  83        if (!space.length)
  84                return AE_NOT_FOUND;
  85
  86        *base = space.base;
  87        *length = space.length;
  88        return AE_OK;
  89}
  90
  91acpi_status hp_acpi_csr_space(acpi_handle obj, u64 *csr_base, u64 *csr_length)
  92{
  93        acpi_status status;
  94
  95        status = hp_ccsr_locate(obj, csr_base, csr_length);
  96        if (ACPI_SUCCESS(status))
  97                return status;
  98
  99        return hp_crs_locate(obj, csr_base, csr_length);
 100}
 101EXPORT_SYMBOL(hp_acpi_csr_space);
 102