ahci_xgene: Fix the DMA state machine lockup for the ATA_CMD_PACKET PIO mode command.

 * xgene_ahci_qc_issue - Issue commands to the device

 * xgene_ahci_qc_issue - Issue commands to the device

 * @qc: Command to issue

 * @qc: Command to issue

 *

 *

 * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot

 * Due to Hardware errata for IDENTIFY DEVICE command and PACKET

 * clear the BSY bit after receiving the PIO setup FIS. This results in the dma

 * command of ATAPI protocol set, the controller cannot clear the BSY bit

 * state machine goes into the CMFatalErrorUpdate state and locks up. By

 * after receiving the PIO setup FIS. This results in the DMA state machine

 * restarting the dma engine, it removes the controller out of lock up state.

 * going into the CMFatalErrorUpdate state and locks up. By restarting the

 * DMA engine, it removes the controller out of lock up state.

 */

 */

static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)

static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)

{

{

	struct xgene_ahci_context *ctx = hpriv->plat_data;

	struct xgene_ahci_context *ctx = hpriv->plat_data;

	int rc = 0;

	int rc = 0;

	if (unlikely(ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA))

	if (unlikely((ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA) ||

	    (ctx->last_cmd[ap->port_no] == ATA_CMD_PACKET)))

		xgene_ahci_restart_engine(ap);

		xgene_ahci_restart_engine(ap);

	rc = ahci_qc_issue(qc);

	rc = ahci_qc_issue(qc);