+/*
+ * 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.
+ */
+static 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 int vendor_resource_matches(struct pnp_dev *dev,
+ struct acpi_resource_vendor_typed *vendor,
+ struct acpi_vendor_uuid *match,
+ int expected_len)
+{
+ int uuid_len = sizeof(vendor->uuid);
+ u8 uuid_subtype = vendor->uuid_subtype;
+ u8 *uuid = vendor->uuid;
+ int actual_len;
+
+ /* byte_length includes uuid_subtype and uuid */
+ actual_len = vendor->byte_length - uuid_len - 1;
+
+ if (uuid_subtype == match->subtype &&
+ uuid_len == sizeof(match->data) &&
+ memcmp(uuid, match->data, uuid_len) == 0) {
+ if (expected_len && expected_len != actual_len) {
+ dev_err(&dev->dev, "wrong vendor descriptor size; "
+ "expected %d, found %d bytes\n",
+ expected_len, actual_len);
+ return 0;
+ }
+
+ return 1;
+ }
+
+ return 0;
+}
+
+static void pnpacpi_parse_allocated_vendor(struct pnp_dev *dev,
+ struct acpi_resource_vendor_typed *vendor)
+{
+ if (vendor_resource_matches(dev, vendor, &hp_ccsr_uuid, 16)) {
+ u64 start, length;
+
+ memcpy(&start, vendor->byte_data, sizeof(start));
+ memcpy(&length, vendor->byte_data + 8, sizeof(length));
+
+ pnp_add_mem_resource(dev, start, start + length - 1, 0);
+ }
+}
+