diff options
| author | Suman Tripathi <stripathi@apm.com> | 2014-12-29 06:22:47 +0300 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2015-01-05 17:02:56 +0300 |
| commit | 1102407bb714dcebb43f385335bcb72f6b8843bc (patch) | |
| tree | 660b1ace45df70996de19cfdb7d8abca31fd7c69 /drivers/ata/ahci_xgene.c | |
| parent | 5c0b8e0de76a86edb99e46612fd9d341b4c4fa0a (diff) | |
| download | linux-1102407bb714dcebb43f385335bcb72f6b8843bc.tar.xz | |
ahci_xgene: Fix the DMA state machine lockup for the ATA_CMD_PACKET PIO mode command.
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 <stripathi@apm.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/ata/ahci_xgene.c')
| -rw-r--r-- | drivers/ata/ahci_xgene.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c index f190b92786e4..cbcd20810355 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); |