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 25 struct 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 31 static 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 acpi_os_free(buffer.pointer); 54 return status; 55 } 56 57 struct csr_space { 58 u64 base; 59 u64 length; 60 }; 61 62 static 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 80 static 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 93 acpi_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 } 103 EXPORT_SYMBOL(hp_acpi_csr_space); 104