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_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 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