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>
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.
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/acpi.h>
15 #include <asm/acpi-ext.h>
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.
25 struct acpi_vendor_uuid hp_ccsr_uuid = {
27 .data = { 0xf9, 0xad, 0xe9, 0x69, 0x4f, 0x92, 0x5f, 0xab, 0xf6, 0x4a,
28 0x24, 0xd2, 0x01, 0x37, 0x0e, 0xad },
31 static acpi_status hp_ccsr_locate(acpi_handle obj, u64 *base, u64 *length)
34 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
35 struct acpi_resource *resource;
36 struct acpi_resource_vendor_typed *vendor;
38 status = acpi_get_vendor_resource(obj, METHOD_NAME__CRS, &hp_ccsr_uuid,
41 resource = buffer.pointer;
42 vendor = &resource->data.vendor_typed;
44 if (ACPI_FAILURE(status) || vendor->byte_length < 16) {
45 status = AE_NOT_FOUND;
49 memcpy(base, vendor->byte_data, sizeof(*base));
50 memcpy(length, vendor->byte_data + 8, sizeof(*length));
53 kfree(buffer.pointer);
62 static acpi_status find_csr_space(struct acpi_resource *resource, void *data)
64 struct csr_space *space = data;
65 struct acpi_resource_address64 addr;
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;
77 return AE_OK; /* keep looking */
80 static acpi_status hp_crs_locate(acpi_handle obj, u64 *base, u64 *length)
82 struct csr_space space = { 0, 0 };
84 acpi_walk_resources(obj, METHOD_NAME__CRS, find_csr_space, &space);
89 *length = space.length;
93 acpi_status hp_acpi_csr_space(acpi_handle obj, u64 *csr_base, u64 *csr_length)
97 status = hp_ccsr_locate(obj, csr_base, csr_length);
98 if (ACPI_SUCCESS(status))
101 return hp_crs_locate(obj, csr_base, csr_length);
103 EXPORT_SYMBOL(hp_acpi_csr_space);