From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Suman Tripathi , Tejun Heo , Sasha Levin Subject: [PATCH 3.18 040/144] ahci_xgene: Fix the DMA state machine lockup for the ATA_CMD_PACKET PIO mode command. Date: Thu, 8 Nov 2018 13:50:11 -0800 Message-Id: <20181108215057.767584746@linuxfoundation.org> In-Reply-To: <20181108215054.826084593@linuxfoundation.org> References: <20181108215054.826084593@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 1102407bb714dcebb43f385335bcb72f6b8843bc ] This patch addresses the issue with ATA_CMD_PACKET pio mode command for enumeration and device detection with ATAPI devices. The X-Gene AHCI controller has an errata in which it cannot clear the BSY bit after the PIO setup FIS. The dma state machine enters CMFatalErrorUpdate state and locks up. Signed-off-by: Suman Tripathi Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin --- drivers/ata/ahci_xgene.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c index 0ffd3c930bed..d33216155827 100644 --- a/drivers/ata/ahci_xgene.c +++ b/drivers/ata/ahci_xgene.c @@ -125,10 +125,11 @@ static int xgene_ahci_restart_engine(struct ata_port *ap) * xgene_ahci_qc_issue - Issue commands to the device * @qc: Command to issue * - * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot - * clear the BSY bit after receiving the PIO setup FIS. This results in the dma - * state machine goes into the CMFatalErrorUpdate state and locks up. By - * restarting the dma engine, it removes the controller out of lock up state. + * Due to Hardware errata for IDENTIFY DEVICE command and PACKET + * command of ATAPI protocol set, the controller cannot clear the BSY bit + * after receiving the PIO setup FIS. This results in the DMA state machine + * 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) { @@ -137,7 +138,8 @@ static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc) struct xgene_ahci_context *ctx = hpriv->plat_data; 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); rc = ahci_qc_issue(qc); -- 2.17.1