linux/arch/ia64/kernel/acpi-ext.c
2006-07-01 17:19:08 -04:00

104 lines
2.7 KiB
C

/*
* (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
* Alex Williamson <alex.williamson@hp.com>
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/acpi.h>
#include <asm/acpi-ext.h>
/*
* Device CSRs that do not appear in PCI config space should be described
* via ACPI. This would normally be done with Address Space Descriptors
* marked as "consumer-only," but old versions of Windows and Linux ignore
* the producer/consumer flag, so HP invented a vendor-defined resource to
* describe the location and size of CSR space.
*/
struct acpi_vendor_uuid hp_ccsr_uuid = {
.subtype = 2,
.data = { 0xf9, 0xad, 0xe9, 0x69, 0x4f, 0x92, 0x5f, 0xab, 0xf6, 0x4a,
0x24, 0xd2, 0x01, 0x37, 0x0e, 0xad },
};
static acpi_status hp_ccsr_locate(acpi_handle obj, u64 *base, u64 *length)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_resource *resource;
struct acpi_resource_vendor_typed *vendor;
status = acpi_get_vendor_resource(obj, METHOD_NAME__CRS, &hp_ccsr_uuid,
&buffer);
resource = buffer.pointer;
vendor = &resource->data.vendor_typed;
if (ACPI_FAILURE(status) || vendor->byte_length < 16) {
status = AE_NOT_FOUND;
goto exit;
}
memcpy(base, vendor->byte_data, sizeof(*base));
memcpy(length, vendor->byte_data + 8, sizeof(*length));
exit:
kfree(buffer.pointer);
return status;
}
struct csr_space {
u64 base;
u64 length;
};
static acpi_status find_csr_space(struct acpi_resource *resource, void *data)
{
struct csr_space *space = data;
struct acpi_resource_address64 addr;
acpi_status status;
status = acpi_resource_to_address64(resource, &addr);
if (ACPI_SUCCESS(status) &&
addr.resource_type == ACPI_MEMORY_RANGE &&
addr.address_length &&
addr.producer_consumer == ACPI_CONSUMER) {
space->base = addr.minimum;
space->length = addr.address_length;
return AE_CTRL_TERMINATE;
}
return AE_OK; /* keep looking */
}
static acpi_status hp_crs_locate(acpi_handle obj, u64 *base, u64 *length)
{
struct csr_space space = { 0, 0 };
acpi_walk_resources(obj, METHOD_NAME__CRS, find_csr_space, &space);
if (!space.length)
return AE_NOT_FOUND;
*base = space.base;
*length = space.length;
return AE_OK;
}
acpi_status hp_acpi_csr_space(acpi_handle obj, u64 *csr_base, u64 *csr_length)
{
acpi_status status;
status = hp_ccsr_locate(obj, csr_base, csr_length);
if (ACPI_SUCCESS(status))
return status;
return hp_crs_locate(obj, csr_base, csr_length);
}
EXPORT_SYMBOL(hp_acpi_csr_space);