摘要:
A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.
摘要:
A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.
摘要:
A method for accessing hardware I/O control blocks, which are stored in an hardware I/O control block array, by a parallel SCSI host adapter addresses one page in a plurality of pages of the hardware I/O control block array for the parallel SCSI host adapter using a first portion of a hardware I/O control block array pointer in the parallel SCSI host adapter. The one page includes a plurality of storage sites for hardware I/O control blocks. A hardware I/O control block stored in the one page is addressed using a second portion of the hardware I/O control block array pointer in the parallel SCSI host adapter. Addressing the hardware I/O control block stored in the one page includes using a tag supplied by a reconnecting SCSI target as the second portion.
摘要:
A parallel SCSI host adapter uses an expanded SCB array for both non-Packetized and Packetized SCSI Protocols. The expanded SCB array is partitioned into a low page and a high page. SCBs for non-Packetized SCSI Protocol target devices that utilize a one-byte tag are stored in the low page and the storage site number is the tag. SCBs for Packetized SCSI Protocol target devices that utilize a multi-byte tag are stored on both the low page and the high page. For Packetized SCSI Protocol target devices, the two-bytes required to identify the page and the number of the storage site in the page are used as the tag. SCBs for Packetized SCSI Protocol target devices are stored in the low page only if there are no available storage sites in the high page.
摘要:
A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.
摘要:
A method for flow control by a SCSI system using a Packetized SCSI Protocol includes transferring a data packet information unit in a Packetized SCSI Protocol Data Out phase between a SCSI initiator and a SCSI target over a SCSI bus. The method also includes generating a signal on said SCSI bus by said SCSI target in said Packetized SCSI Protocol Data Out phase to indicate whether another data packet information unit is to be accepted in said Packetized SCSI Protocol Data Out phase by said SCSI Target.
摘要:
A method for data streaming by a SCSI target includes transmitting a data packet information unit in a Packetized SCSI Protocol Data In phase. The SCSI target also generates a signal during the Packetized SCSI Protocol Data In phase to indicate whether a header packet information unit or another data packet information unit is to be transmitted next in the Packetized SCSI Protocol Data In phase.
摘要:
A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.
摘要:
A parallel host adapter that interfaces two I/O buses includes at least two independent data channels, a receive data channel and a send data channel. The receive data channel supports at least two data contexts. The parallel host adapter also includes an administrative information channel that couples one of the I/O buses to a memory where administrative information for the parallel host adapter is stored. The send data channel includes a send buffer memory, and a data transfer engine. The data transfer engine is coupled to a first port of the send buffer memory and to a first I/O bus coupled to the parallel host adapter. The send buffer memory is a single data context buffer memory. The receive data channel includes a receive buffer memory, and another data transfer engine. The another data transfer engine is coupled to the first I/O bus and to a first port of the receive buffer memory. Data for a first data context is transferred from the second I/O bus to the receive buffer memory through a second port of the receive buffer memory. The data in the first data context is transferred from the receive buffer memory to the first I/O bus by the another data transfer engine. As this is happening, data from a second data context can be transferred from the second I/O bus to the receive buffer memory. Also, as the receive buffer memory is emptying, the send buffer memory may be receiving data.
摘要:
A method for suspending and resuming execution of firmware routines facilitates high speed concurrent processing within a multi-tasking integrated circuit that interfaces a first input/output (I/O) bus with a second input/output bus. The method uses a single instruction in a first executing routine to save a return address, and to transfer execution to a second routine. Similarly, a single return instruction in the second routine is used to restore the return address and to transfer execution from the second routine to the first routine. The use of single instructions in the two routines reduces the silicon area required to store the firmware, and enhances execution performance.