+ * ata_acpi_gtm_xfermode - determine xfermode from GTM parameter
+ * @dev: target device
+ * @gtm: GTM parameter to use
+ *
+ * Determine xfermask for @dev from @gtm.
+ *
+ * LOCKING:
+ * None.
+ *
+ * RETURNS:
+ * Determined xfermask.
+ */
+unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
+ const struct ata_acpi_gtm *gtm)
+{
+ unsigned long xfer_mask = 0;
+ unsigned int type;
+ int unit;
+ u8 mode;
+
+ /* we always use the 0 slot for crap hardware */
+ unit = dev->devno;
+ if (!(gtm->flags & 0x10))
+ unit = 0;
+
+ /* PIO */
+ mode = ata_timing_cycle2mode(ATA_SHIFT_PIO, gtm->drive[unit].pio);
+ xfer_mask |= ata_xfer_mode2mask(mode);
+
+ /* See if we have MWDMA or UDMA data. We don't bother with
+ * MWDMA if UDMA is available as this means the BIOS set UDMA
+ * and our error changedown if it works is UDMA to PIO anyway.
+ */
+ if (!(gtm->flags & (1 << (2 * unit))))
+ type = ATA_SHIFT_MWDMA;
+ else
+ type = ATA_SHIFT_UDMA;
+
+ mode = ata_timing_cycle2mode(type, gtm->drive[unit].dma);
+ xfer_mask |= ata_xfer_mode2mask(mode);
+
+ return xfer_mask;
+}
+EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);
+
+/**
+ * ata_acpi_cbl_80wire - Check for 80 wire cable
+ * @ap: Port to check
+ * @gtm: GTM data to use
+ *
+ * Return 1 if the @gtm indicates the BIOS selected an 80wire mode.
+ */
+int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
+{
+ struct ata_device *dev;
+
+ ata_for_each_dev(dev, &ap->link, ENABLED) {
+ unsigned long xfer_mask, udma_mask;
+
+ xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
+ ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);
+
+ if (udma_mask & ~ATA_UDMA_MASK_40C)
+ return 1;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);
+
+static void ata_acpi_gtf_to_tf(struct ata_device *dev,
+ const struct ata_acpi_gtf *gtf,
+ struct ata_taskfile *tf)
+{
+ ata_tf_init(dev, tf);
+
+ tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+ tf->protocol = ATA_PROT_NODATA;
+ tf->feature = gtf->tf[0]; /* 0x1f1 */
+ tf->nsect = gtf->tf[1]; /* 0x1f2 */
+ tf->lbal = gtf->tf[2]; /* 0x1f3 */
+ tf->lbam = gtf->tf[3]; /* 0x1f4 */
+ tf->lbah = gtf->tf[4]; /* 0x1f5 */
+ tf->device = gtf->tf[5]; /* 0x1f6 */
+ tf->command = gtf->tf[6]; /* 0x1f7 */
+}
+
+static int ata_acpi_filter_tf(struct ata_device *dev,
+ const struct ata_taskfile *tf,
+ const struct ata_taskfile *ptf)
+{
+ if (dev->gtf_filter & ATA_ACPI_FILTER_SETXFER) {
+ /* libata doesn't use ACPI to configure transfer mode.
+ * It will only confuse device configuration. Skip.
+ */
+ if (tf->command == ATA_CMD_SET_FEATURES &&
+ tf->feature == SETFEATURES_XFER)
+ return 1;
+ }
+
+ if (dev->gtf_filter & ATA_ACPI_FILTER_LOCK) {
+ /* BIOS writers, sorry but we don't wanna lock
+ * features unless the user explicitly said so.
+ */
+
+ /* DEVICE CONFIGURATION FREEZE LOCK */
+ if (tf->command == ATA_CMD_CONF_OVERLAY &&
+ tf->feature == ATA_DCO_FREEZE_LOCK)
+ return 1;
+
+ /* SECURITY FREEZE LOCK */
+ if (tf->command == ATA_CMD_SEC_FREEZE_LOCK)
+ return 1;
+
+ /* SET MAX LOCK and SET MAX FREEZE LOCK */
+ if ((!ptf || ptf->command != ATA_CMD_READ_NATIVE_MAX) &&
+ tf->command == ATA_CMD_SET_MAX &&
+ (tf->feature == ATA_SET_MAX_LOCK ||
+ tf->feature == ATA_SET_MAX_FREEZE_LOCK))
+ return 1;
+ }
+
+ if (tf->command == ATA_CMD_SET_FEATURES &&
+ tf->feature == SETFEATURES_SATA_ENABLE) {
+ /* inhibit enabling DIPM */
+ if (dev->gtf_filter & ATA_ACPI_FILTER_DIPM &&
+ tf->nsect == SATA_DIPM)
+ return 1;
+
+ /* inhibit FPDMA non-zero offset */
+ if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_OFFSET &&
+ (tf->nsect == SATA_FPDMA_OFFSET ||
+ tf->nsect == SATA_FPDMA_IN_ORDER))
+ return 1;
+
+ /* inhibit FPDMA auto activation */
+ if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_AA &&
+ tf->nsect == SATA_FPDMA_AA)
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * ata_acpi_run_tf - send taskfile registers to host controller