Abstract: A computer program product and distributed data processing system that allows a single physical I/O adapter, such as a PCI, PCI-X, or PCI-E adapter, to validate that a direct memory access address referenced by an incoming I/O transaction that was initiated through a memory mapped I/O operation are associated with a virtual adapter or virtual resource that is referenced by the incoming memory mapped I/O operation is provided. Specifically, the present invention is directed to a mechanism for sharing conventional PCI (Peripheral Component Interconnect) I/O adapters, PCI-X I/O Adapters, PCI-Express I/O Adapters, and, in general, any I/O adapter that uses a memory mapped I/O interface for communications. A single physical I/O adapter validates that one or more direct memory access addresses referenced by an incoming I/O transaction initiated through a memory mapped I/O operation are associated with a virtual adapter or virtual resource that is referenced by the incoming memory mapped I/O operation.

Abstract: One embodiment provides a system which uses a temporal ordering policy for allocation of limited processor resources. The system starts by executing instructions for a program during a normal-execution mode. Upon encountering a condition which causes the processor to enter a speculative-execution mode, the processor performs a checkpoint and commences execution of instructions in the speculative-execution mode. Upon encountering an instruction which requires the allocation of an instance of a limited processor resource during the execution of instructions in the speculative-execution mode, the processor checks a speculative-use indicator associated with each instance of the limited processor resource. Upon finding the speculative-use indicators asserted for all instances of the limited processor resource which are available to be allocated for the instruction, the processor aborts the instruction.

Abstract: A DMA circuit operates a plurality of DMA channels in parallel, enabling reduction of the circuit scale and fewer development processes. A channel manager circuit reads in sequence the control information for each DMA channel from control memory, performs analysis, and according to the divided DMA control sequence, performs state processing (DMA control). Further, the channel manager circuit updates the control information, writes back the control information to the control memory, and executes time-division control of the plurality of DMA channels. Hence the circuit scale can be reduced, contributing to decreased costs, and the number of development processes can be reduced.

Abstract: A method, apparatus, and program product access memory resources of a computer using a group of direct access memory (DMA) devices. A first DMA device is designated a primary device after association with an active translation table (ATT), while a second DMA device is designated a backup device after association with an inactive translation table (ITT). A translation is entered into the ATT for the first DMA device to permit it to perform a DMA operation, while a translation is inhibited from being entered into the ITT for a second DMA device to prevent it from performing a DMA operation. Thereafter, the roles of the first and second DMA devices may be swapped by associating the first DMA device with the ITT and associating the second DMA device with the ATT. The computer may be a logically partitioned computer of the type that includes a plurality of logical partitions.

Abstract: Method and apparatus for communication between hardware blocks configured in a programmable logic device (PLD) and a computation device external to the PLD is described. A bus controller is provided for receiving words from the computation device. Each of the words includes an address component and a data component. A first-in-first-out buffer (FIFO) is configured for communication with the bus controller to store the words. A processing engine is provided having a memory space associated with the hardware blocks and being configured to receive a word at a top of the FIFO. An address decoder is provided for decoding the address component of the word at the top of the FIFO to obtain an address of a memory location in the memory space. A strobe generator is provided for coupling a strobe signal to the processing engine. The strobe signal is configured to store the word in the memory location.

Abstract: A data transfer control device includes a PATA I/F connected to a PATA bus, an SATA I/F connected to an SATA bus, and a sequence controller that controls a transfer sequence. The PATA I/F includes a task file register (TFR). The sequence controller suspends transmission of a register FIS corresponding to an ATA packet command issued by a host to a device, and performs a dummy setting that causes the host to issue an ATAPI packet command using the TFR. The sequence controller transmits the register FIS corresponding to the ATA packet command to the device after the host has issued the ATAPI packet command.

Abstract: A method of providing access to first data stored at a first device to a second device, the first device storing the first data in a memory accessible to said second device. The method comprises, at a control element distinct from each of said first and second devices accessing the stored first data in said memory accessible to said second device before said first data is accessed in said memory accessible to said second device by said second device.

Abstract: An interface controller connected to a read request device which performs a read request to a storage device stored with data, includes a receiving buffer which stores a read response of said storage device with respect to the read request sent from said read request device; and a control unit which performs read request authorization to said read request device on the basis of a capacity of said receiving buffer, a read request size and a read response size.

Abstract: A direct memory access controller has a data register for transferring data from a source to a destination address. A pattern register is provided and a data comparator is coupled with the data register and the pattern register for comparing the content of the data register with the content of the pattern register. A control unit coupled with the comparator controls the data flow and stops a data transfer if the comparator detects a match of the data register and the pattern register.

Abstract: A computer system includes a CPU (Central Processing Unit) and a main storage interconnected by a bus to the CPU. The I/O module for transferring received data and data to be transmitted to and from an external unit is directly connected to the main storage, which stores the received data or the transmission data, so that data transfer can be effected every minimum data cycle that allows an access to a memory macro included in the main storage. This accomplishes high-speed data transfer based on DMA (Direct Memory Access) transfer over the bus.

Abstract: The subject disclosure pertains to transparent communications in an industrial automation environment amongst automation system components and IT systems. Systems and methods are provided that send and receive data to, from and amongst automation devices and transactional based IT systems. The system is viewed as a control system to the automation device and as a transactional system to the IT system. Accordingly, it is not necessary to provide a custom interface between automation devices and the IT systems.

Abstract: A data processing apparatus and a program data setting method that can minimize a manufacturing cost. The data processing apparatus includes a plurality of In System Programming (ISP) devices to store program data used to drive the data processing apparatus, a connector to receive the program data from an external program providing device, and a switch to switch a connection between the connector and the plurality of ISP devices. The data processing apparatus can adjust the connection between the connector and the plurality of ISP devices using the switch. Accordingly, the data processing apparatus does not require an additional connector or a separate program to distribute the program data received at the connector to each ISP device so that the manufacturing cost can be minimized and a structure can be simplified.

Abstract: In a computer system employing PCI Express (PCIe) links, the PCIe bandwidth is increased by configuring an endpoint device with at least two PCIe interfaces, and coupling the first of these interfaces with a PCIe interface of a system controller and the second of these PCIe interfaces with an expansion PCIe interface of an I/O controller. Therefore, the endpoint device's performance becomes more efficient. For example, if the endpoint device is a graphics processing unit, then the endpoint device can execute more frames per second. When a read request is split up and issued as multiple read requests over the at least two PCIe interfaces, the multiple read completion packets that are received in response thereto are ordered in accordance with the timing of the multiple read requests.

Abstract: According to one embodiment a method for implementing bufferless DMA controllers using split transaction functionality is presented. One embodiment of the method comprises, generating a write command from a disk controller directed to a destination unit, the write command including an identifier, generating a read command from the disk controller directed to a source unit, the read command including an identifier which matches the identifier in the write command, the source unit transmitting read data on a split transaction bus, the read data including the identifier of the read command, and receiving the read data at the destination unit via the split transaction bus if the identifier of the read data matches the identifier of the write command.

Abstract: Methods and apparatus provide for transferring a plurality of data blocks between a shared memory and a local memory of a processor in response to a single DMA command issued by the processor to a direct memory access controller (DMAC), wherein the processor is capable of operative communication with the shared memory and the DMAC is operatively coupled to the local memory.

Abstract: Provided is an information processing apparatus and method of controlling same in which, when data transfer is performed among a plurality of control circuits, which control circuit is used to execute data transfer is controlled appropriately based on the transfer conditions of data transfer. To accomplish this, the apparatus has first and second control circuits, a request for data transfer performed between the first and second control circuits is acquired, the transfer conditions of the acquired data transfer are analyzed and which of the first and second control circuits is to execute the data transfer is selected.

Abstract: A computer that operates in a metered mode for normal use and a restricted mode uses an input/output memory management unit (I/O MMU) in conjunction with a security policy to determine which peripheral devices are allowed direct memory access during the restricted mode of operation. During restricted mode operation, non-authorized peripheral devices are removed from virtual address page tables or given vectors to non-functioning memory areas.

Abstract: An enhanced fibre channel adapter with multiple queues for use by different server processors or partitions. For a non-partitioned server, the OS owns the adapter, controls the adapter queues, and updates the queue table(s). An OS operator can obtain information from the fibre channel network about the fibre channel storage data zones available to the physical fibre channel adapter port and can specify that one or more zones can be accessed by a specific processor or group of processors. The processor or group of processors is given an adapter queue to access the zone or zones of storage data. This queue is given a new World Wide Port Name or new N-Port ID Virtualization identifier, to differentiate this queue from another queue that might have access to a different storage data zone or zones. For a partitioned server, one partition owns the adapter, controls the adapter queues, and updates the queue table(s).

Abstract: A bus bridge between a high speed DMA bus and a lower speed peripheral bus sets a threshold for minimum available buffer space to send a read request dependent upon a frequency ratio and the DMA read latency. Similarly, a threshold for minimum available data for a write request depends on the frequency ratio and the DMA write latency. The bus bridge can store programmable values for the DMA read latency and write latency.

Abstract: A data transfer device for performing direct memory access (DMA) transfer of data stored in a storage unit to a plurality of other devices includes: a plurality of channel units arranged to correspond to the other devices, the channel units retaining DMA transfer instructions, and outputting number of the DMA transfer instructions retained; a plurality of priority controllers for determining priorities of the channel units on the basis of the number of the DMA transfer instructions retained in the channel units, respectively; an arbiter for selecting one of the DMA transfer instructions retained in one of the channel units on the basis of the priorities determined by the priority controller; and a data transfer processor for performing DMA transfer of data stored in the storage unit to one of the other devices in accordance with the DMA transfer instruction selected by the arbiter.

Abstract: The present invention provides a method and a system for providing cache management commands in a system supporting a DMA mechanism and caches. A DMA mechanism is set up by a processor. Software running on the processor generates cache management commands. The DMA mechanism carries out the commands, thereby enabling the software program management of the caches. The commands include commands for writing data to the cache, loading data from the cache, and for marking data in the cache as no longer needed. The cache can be a system cache or a DMA cache.

Abstract: A system having memory access capabilities, the system includes: (i) a dynamic voltage and frequency scaling (DVFS) controller, adapted to determine a level of a voltage supply supplied to a first memory access requester and a frequency of a clock signal provided to the first memory access requester and to generate a DVFS indication that is indicative of the determination; (ii) a hardware access request determination module, adapted to determine a priority of memory access request issued by the first memory access requester in response to the DVFS indication; and (iii) a direct memory access arbitrator, adapted to arbitrate between memory access requests issued by the first memory access requester and another memory access requester in response to priorities associated with the memory access requests.

Abstract: Provided is a unit for protecting data with respect to data transfer between memories of a disk controller. The disk controller for controlling data transfer between a host computer and a disk drive includes: a channel unit having a channel memory; a cache unit having a cache memory, and a control unit for controlling the data transfer. The data transferred to/from the host computer is transferred in a packet between the channel memory and the cache memory, and The control unit for verifying consistency of information included in a header of the packet to be transferred to decide whether transfer can be permitted when the packet is transferred.

Abstract: A method and system for memory address translation and pinning are provided. The method includes attaching a memory address space identifier to a direct memory access (DMA) request, the DMA request is sent by a consumer and using a virtual address in a given address space. The method further includes looking up for the memory address space identifier to find a translation of the virtual address in the given address space used in the DMA request to a physical page frame. Provided that the physical page frame is found, pinning the physical page frame al song as the DMA request is in progress to prevent an unmapping operation of said virtual address in said given address space, and completing the DMA request, wherein the steps of attaching, looking up and pinning are centrally controlled by a host gateway.

Abstract: The serial communication device capable of reducing the load on the CPU is provided for a system using the serial communications such as the car navigation system. The attention is focused on the control method of the serial communication, in which a DMA controller is used for the data reception in the serial communication, and a number larger than the number of data received at a time is set in advance as the number of transfers of the receive DMA controller, and further, the function to generate the timeout interrupt when data is not received for a certain period is added to the serial interface, so that the serial communication can be controlled and performed without applying the load on the CPU.

Abstract: A network storage controller uses a non-volatile solid-state memory (NVSSM) subsystem which includes raw flash memory as stable storage for data, and uses remote direct memory access (RDMA) to access the NVSSM subsystem, including to access the flash memory. Storage of data in the NVSSM subsystem is controlled by an external storage operating system in the storage controller. The storage operating system uses scatter-gather lists to specify the RDMA read and write operations. Multiple client-initiated reads or writes can be combined in the storage controller into a single RDMA read or write, respectively, which can then be decomposed and executed as multiple reads or writes, respectively, in the NVSSM subsystem. Memory accesses generated by a single RDMA read or write may be directed to different memory devices in the NVSSM subsystem, which may include different forms of non-volatile solid-state memory.

Abstract: A method, apparatus, and program product access memory resources of a computer using a group of direct access memory (DMA) devices. A first DMA device is designated a primary device after association with an active translation table (ATT), while a second DMA device is designated a backup device after association with an inactive translation table (ITT). A translation is entered into the ATT for the first DMA device to permit it to perform a DMA operation, while a translation is inhibited from being entered into the ITT for a second DMA device to prevent it from performing a DMA operation. Thereafter, the roles of the first and second DMA devices may be swapped by associating the first DMA device with the ITT and associating the second DMA device with the ATT. The computer may be a logically partitioned computer of the type that includes a plurality of logical partitions.

Abstract: The present invention relates to a Direct Memory Access controller that, in an embodiment, executes I/O descriptors conditionally. A linked list item contains a checksum computed on the descriptor fields. When the linked list item is fetched, the checksum is computed on the descriptor. If both checksums are equal, the linked list item is considered valid and the descriptor is executed. At the end of a DMA I/O, the next descriptor in the linked list is fetched. When the checksum fails, the descriptor is corrupted and the channel is stopped and an error is reported to the operating system.

Abstract: A computer system according to an example of the invention comprises SPEs and a global memory. The SPEs include a running SPE and an idling SPE. The running SPE and the idling SPE each have a processor core, local memory and DMA module. The local memory of the idling SPE stores data stored in the global memory and used by the processor core of the running SPE, before the data is used by the processor core of the running SPE. The DMA module of the running SPE reads the data from the local memory of the idling SPE, and transfers the data to the processor core of the running SPE.

Abstract: DMAC includes current transfer setting registers and next transfer setting registers. Each of the current transfer setting registers stores transfer source address, transfer destination address and transfer count. The next transfer setting registers stores a transfer setting of a DMA transfer carried out after completing a DMA transfer according to a current transfer setting stored in the current transfer setting registers as a next transfer setting. Further, flags are provided for controlling to write to each of the next transfer setting registers.

Abstract: A DMA controller includes at least one peripheral DMA channel for handling DMA transfers on a peripheral access bus; at least one memory DMA stream, including a memory destination channel and a memory source channel, for handling DMA transfers on first and second memory access buses; first and second address computation units for computing updated memory addresses for DMA transfers; first and second memory pipelines for supplying memory addresses to the first and second memory access buses, respectively, and for transferring data on the first and second memory access buses; and a multiplexer configured to supply first and second current memory addresses to selected ones of the first and second memory pipelines in response to a control signal.

Abstract: The image processing apparatus (data processing apparatus) stores data in a storing unit (storing means), inputs and outputs the data to and from the storing unit via a storage control unit (input-output means) and processes the data outputted from the storing unit with a control unit (processing means). The storage control unit inputs and outputs image data to and from the storing unit by the DMA method through a path via a DMA control unit and inputs and outputs other data such as a control instruction to and from the storing unit by the PIO method through a path via a PIO control unit. Image data to be inputted and outputted to and from the storing unit by the DMA method is encrypted in an input operation and decrypted in an output operation by an encryption/decryption unit provided on the input-output path for DMA method.

Abstract: A direct memory access system utilizing a local memory that stores a plurality of DMA command lists, each comprising at least one DMA command. A command queue can hold a plurality of entries, each entry comprising a pointer field and a sequence field. The pointer field points to one of the DMA command lists. The sequence field holds a sequence value. A DMA engine accesses an entry in the command queue and then accesses the DMA commands of the DMA command list pointed to by the pointer field of the accessed entry. The DMA engine performs the DMA operations specified by the accessed DMA commands. The DMA engine makes available the sequence value held in the sequence field of the accessed entry when all of the DMA commands in the accessed command list have been performed. In one embodiment, the command queue is part of the DMA engine.

Abstract: A method and apparatus for providing file system operation locks at a database server is provided. A database server may employ database locks and file system operation locks in servicing requests from consistent requestors and inconsistent requesters. A database lock is a lock that is obtained in response to performing a database operation, and the database lock is released when the database operation has successfully completed. A file system operation lock is a lock that is obtained in response to performing an OPEN file system operation, and the file system operation lock is released when a CLOSE file system operation is performed. The database server may use a temporary copy of the resource, which reflects all the current changes that have been made to the resource by database operations, in servicing consistent requestors, and may use the original version of the resource in servicing inconsistent requesters.

Abstract: A method, system and program are provided for dynamically allocating DMA channel identifiers by virtualizing DMA transfer requests into available DMA channel identifiers using a channel bitmap listing of available DMA channels to select and set an allocated DMA channel identifier. Once an input value associated with the DMA transfer request is mapped to the selected DMA channel identifier, the DMA transfer is performed using the selected DMA channel identifier, which is then deallocated in the channel bitmap upon completion of the DMA transfer. When there is a request to wait for completion of the data transfer, the same input value is used with the mapping to wait on the appropriate logical channel. With this method, all available logical channels can be utilized with reduced instances of false-sharing.

Abstract: A data transfer control apparatus includes a channel controller and a transfer controller. The channel controller receives, prioritizes and queues event signals and predetermined memory writes which trigger data transfer requests controlling the transfer controller. The event queue stores event numbers mapped to parameter memory locations storing data transfer parameters. The mapping table and the parameter memory are writeable via a memory mapped write operation. Memory protection registers store data indicative of permitted data accesses to the memory map.

Abstract: A data transfer control apparatus includes a channel controller and plural transfer controllers. The channel controller receives, prioritizes and queues data transfer requests. An event to transfer controller table enables recall of a transfer controller number corresponding to the data transfer request. The plural transfer controllers are independent and can operate simultaneously in parallel. Each transfer controller includes a read bus interface and a write bus interface which arbitrate with other bus masters in the case of blocking accesses directed to interfering devices or address ranges.

Abstract: The management apparatus of web servers of the present invention monitors occurrence of link breakage set by requesting to other sites. For this purpose, log information resulting from an access from an external web site to HTTP contents is acquired from the web server. Then, refer information is generated by extracting the linking relationship with the external web site to the web page from the thus acquired log information. Furthermore, upon update of the HTTP contents, the possibility of occurrence of link breakage caused by page deletion is recognized with reference to refer information, and warning is issued.

Abstract: A memory controller for a wireless communication system comprises a packet buffer write system and a packet buffer read system. The packet buffer write system places packets including packet header and packet data into a packet buffer. The packet buffer read system removes packets including a packet header and packet data from a packet buffer. The packet buffer is arranged into a plurality of packet buffer memory slots, each slot comprising a descriptor status array location including an availability bit set to “used” or “free”, and a packet buffer memory location comprising a descriptor memory slot and a data segment memory slot. The descriptor memory slot includes header information for each packet, and the data segment memory slot includes packet data. The memory controller operates on one or more queues of data, and data is placed into a particular queue in packet memory determined by priority information derived from incoming packet header or packet data.

Abstract: A driver for a data storage device includes an access command and a verification command. The access command initiates an access (write, erase or read) of the data storage device while allowing a calling application to continue running without having to wait for the completion of the access. The verification command queries a preceding access. If the query indicates failure of the preceding access, the verification command repeats the preceding access until the preceding access succeeds. The verification command is called by the access command before the access command initiates a new access. The verification command also is called by an application following a sequence of related access command calls. A write access command saves the data to be written in a memory separate from the data storage device, in case the verification command needs that data to repeat a failed write.

Abstract: An apparatus includes a controller and a plurality of disk drives. The controller has a communication control unit for accepting a data input/output request, a disk controller unit for controlling a disk drive, and a cache memory for temporarily storing data transferred between the communication control unit and the disk controller unit. The plurality of disk drives has different communication interfaces and connected to the disk controller unit to communicate with the disk controller unit.

Abstract: An I/O controller to which an I/O device is connected includes a DMA controller (DMAC) and an access control unit (ACU). The DMAC executes DMA transfer in accordance with data transfer control information set in a control/status register by a user process. The ACU limits execution of DMA transfer by the DMAC based on access control information set in a control/status register by a privileged process, and disables the DMAC from accessing any memory area other than the memory area that can be accessed by the user process.

Abstract: A direct memory access (DMA) device is structured as a loosely coupled DMA engine (DE) and a bus engine (BE). The DE breaks the programmed data block moves into separate transactions, interprets the scatter/gather descriptors, and arbitrates among channels. The DE and BE use a combined read-write (RW) command that can be queued between the DE and the BE. The bus engine (BE) has two read queues and a write queue. The first read queue is for “new reads” and the second read queue is for “old reads,” which are reads that have been retried on the bus at least once. The BE gives absolute priority to new reads, and still avoids deadlock situations.

Abstract: An improved system and approaches for protecting secured files when being used by an application (e.g., network browser) that potentially transmits the files over a network to unknown external locations are disclosed. According to one aspect, access to secured files is restricted so that unsecured versions of the secured files are not able to be transmitted over a network (e.g., the Internet) to unauthorized destinations. In one embodiment, in opening a file for use by a network browser, the network browser receives a secured (e.g., encrypted) version of the secured file when the destination location (e.g., destination address) for the network browser is not trusted, but receives an unsecured (e.g., unencrypted) version of the secured file when the destination location for the network browser is trusted.

Abstract: A resource management system including a plurality of requester elements competing to access a resource through an arbiter element that controls access to the resource by the requester elements. A requester element having a buffer unit and first and second counters, which are compared to determine if a request having an identified priority type is in the buffer unit.

Abstract: Attempts by drivers of a virtualized legacy computer game to communicate with nonexistent legacy game system hardware are converted into calls to actual hardware of the host computer game system. An access control list (ACL) restricting and/or reducing page permissions is used to explicitly forbid the drivers of the legacy computer game operating on the virtualized legacy computer game platform from writing to the MMIO addresses of the legacy computer game system. When the operating system of the virtualized legacy computer game platform attempts to touch its driver memory by writing to the MMIO addresses, the operating system of the host computer game system perceives a memory access violation, suspends the virtual machine implementing the virtualized computer game platform, and passes the intended write to an exception handler of the host operating system.

Abstract: A method, system and computer program product that allows a System Image within a multiple System Image Virtual Server to maintain isolation from the other system images while directly exposing a portion, or all, of its associated System Memory to a shared PCI Adapter without the need for each I/O operation to be analyzed and verified by a component trusted by the LPAR manager.

Abstract: A personal sensing device that may be used for storing personal data and sensed data arbitrates and prioritizes competing requests for memory access from sensing, wireless, and wired interfaces. The personal sensing device enables power efficiency with burst-writes to the memory at higher data rates then an incoming sensor data stream without risk of data loss. Sensing operations coordinated by reconfigurable control logic are partitioned from storage operations coordinated by a multi-port memory controller. The interface between the functional partitioning uses message passing, status/control registers and buffering to reduce or eliminate system interdependencies.

Abstract: A versatile SDIO host controller capable of connecting to standardized general interfaces is provided. An SDIO host controller as a one-chip semiconductor integrated circuit device comprising: at least one core of an SDIO host, the core including an SD host engine and an SD host register set and memory that control the SD host engine; a plurality of CPU interfaces that control the SDIO host; and at least one selector that selects among the CPU interfaces. In particular, the SDIO host controller preferably comprises at least an ATA interface and an ATA-SD protocol conversion engine.

Abstract: A method, computer program product, and distributed data processing system that allows a single physical I/O adapter, such as a PCI, PCI-X, or PCI-E adapter, to validate that a direct memory access address referenced by an incoming I/O transaction that was initiated through a memory mapped I/O operation are associated with a virtual adapter or virtual resource that is referenced by the incoming memory mapped I/O operation is provided. Specifically, the present invention is directed to a mechanism for sharing conventional PCI (Peripheral Component Interconnect) I/O adapters, PCI-X I/O Adapters, PCI-Express I/O Adapters, and, in general, any I/O adapter that uses a memory mapped I/O interface for communications. A single physical I/O adapter validates that one or more direct memory access addresses referenced by an incoming I/O transaction initiated through a memory mapped I/O operation are associated with a virtual adapter or virtual resource that is referenced by the incoming memory mapped I/O operation.