[SCSI] isci: atapi support
Based on original implementation from Jiangbi Liu and Maciej Trela.
ATAPI transfers happen in two-to-three stages. The two stage atapi
commands are those that include a dma data transfer. The data transfer
portion of these operations is handled by the hardware packet-dma
acceleration. The three-stage commands do not have a data transfer and
are handled without hardware assistance in raw frame mode.
stage1: transmit host-to-device fis to notify the device of an incoming
atapi cdb. Upon reception of the pio-setup-fis repost the task_context
to perform the dma transfer of the cdb+data (go to stage3), or repost
the task_context to transmit the cdb as a raw frame (go to stage 2).
stage2: wait for hardware notification of the cdb transmission and then
go to stage 3.
stage3: wait for the arrival of the terminating device-to-host fis and
terminate the command.
To keep the implementation simple we only support ATAPI packet-dma
protocol (for commands with data) to avoid needing to handle the data
transfer manually (like we do for SATA-PIO). This may affect
compatibility for a small number of devices (see
ATA_HORKAGE_ATAPI_MOD16_DMA).
If the data-transfer underruns, or encounters an error the
device-to-host fis is expected to arrive in the unsolicited frame queue
to pass to libata for disposition. However, in the DONE_UNEXP_FIS (data
underrun) case it appears we need to craft a response. In the
DONE_REG_ERR case we do receive the UF and propagate it to libsas.
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/isci/remote_device.h b/drivers/scsi/isci/remote_device.h
index 57ccfc3..e1747ea 100644
--- a/drivers/scsi/isci/remote_device.h
+++ b/drivers/scsi/isci/remote_device.h
@@ -244,6 +244,15 @@
SCI_STP_DEV_NCQ_ERROR,
/**
+ * This is the ATAPI error state for the STP ATAPI remote device.
+ * This state is entered when ATAPI device sends error status FIS
+ * without data while the device object is in CMD state.
+ * A suspension event is expected in this state.
+ * The device object will resume right away.
+ */
+ SCI_STP_DEV_ATAPI_ERROR,
+
+ /**
* This is the READY substate indicates the device is waiting for the RESET task
* coming to be recovered from certain hardware specific error.
*/