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-rw-r--r--arch/ia64/kernel/acpi-ext.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/arch/ia64/kernel/acpi-ext.c b/arch/ia64/kernel/acpi-ext.c
new file mode 100644
index 0000000000..42cd214808
--- /dev/null
+++ b/arch/ia64/kernel/acpi-ext.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
+ * Alex Williamson <alex.williamson@hp.com>
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/slab.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.address_length &&
+ addr.producer_consumer == ACPI_CONSUMER) {
+ space->base = addr.address.minimum;
+ space->length = addr.address.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);