Abstract: A computer systemprovides dynamic memory allocation for graphics. The computer system includes a memory controller, a unified system memory, and memory clients each having access to the system memory via the memory controller. Memory clients can include a graphics rendering engine, a CPU, an image processor, a data compression/expansion device, an input/output device, a graphics back end device. The computer system provides read/write access to the unified system memory, through the memory controller, for each of the memory clients. Translation hardware is included for mapping virtual addresses of pixel buffers to physical memory locations in the unified system memory. Pixel buffers are dynamically allocated as tiles of physically contiguous memory. Translation hardware is implemented in each of the computational devices, which are included as memory clients in the computer system, including primarily the rendering engine.

Abstract: A method and arrangement for a dma transfer mode having multiple transactions is provided. The invention generates a set of transaction entries for a DMA transfer each of which contains information related to the address and command instruction of a transaction. The transaction entries are stored in an address/cmd-output-FIFO. The invention negotiates for the control of the system bus. Upon gaining control of the bus, the commands and address relate to each transaction are sequentially place on the system bus. If the transaction is a read operation, data received back from the system bus is first stored in a data-in-FIFO before being sent to the desired destination. If the transaction is a write operation, the data to be transferred is first stored in a data-out-FIFO before being timely place on the system bus for transferring to the desired destination. In either case, the number of data words transferred is monitored to determine when a transaction is complete.

Abstract: A computer system provides dynamic memory allocation for graphics. The computer system includes a memory controller, a unified system memory, and memory clients each having access to the system memory via the memory controller. Memory clients can include a graphics rendering engine, a CPU, an image processor, a data compression/expansion device, an input/output device, a graphics back end device. The computer system provides read/write access to the unified system memory, through the memory controller, for each of the memory clients. Translation hardware is included for mapping virtual addresses of pixel buffers to physical memory locations in the unified system memory. Pixel buffers are dynamically allocated as tiles of physically contiguous memory. Translation hardware is implemented in each of the computational devices, which are included as memory clients in the computer system, including primarily the rendering engine.

Abstract: A memory system that includes a memory controller and memory modules that provide address and control signals to groups of memory components through multiple busses. In one embodiment, each memory module is coupled to an address/control buss. The use of multiple address/control busses provides the necessary bandwidth so as to allow for fast access and control of memory components. Memory components are grouped into banks of memory components with each bank including three memory components. Memory modules are configured with one, two, four, or more banks of memory components on a given memory module. In one embodiment, the memory system includes six 48-bit memory modules that use SDRAM memory components. The six memory modules are used in a set to form a 288-bit memory word. When 16 Mbit or 64 Mbit memory components are used, this configuration gives a range of memory configurations from 32 megabytes to 2 gigabytes.

Abstract: A memory system that includes a memory controller and memory modules that provide address and control signals to groups of memory components through multiple busses. In one embodiment, each memory module is coupled to an address/control buss. The use of multiple address/control busses provides the necessary bandwidth so as to allow for fast access and control of memory components. Memory components are grouped into banks of memory components with each bank including three memory components. Memory modules are configured with one, two, four, or more banks of memory components on a given memory module. In one embodiment, the memory system includes six 48-bit memory modules that use SDRAM memory components. The six memory modules are used in a set to form a 288-bit memory word. When 16 Mbit or 64 Mbit memory components are used, this configuration gives a range of memory configurations from 32 megabytes to 2 gigabytes.

Abstract: Interlocking of addresses in a system with parallel processors using a common memory space is managed by maintaining for each processor a record of the lock state of the system. When a processor seeks to initiate a transaction, the transaction is analyzed against the lock state record, and the processor's request for access to an intercommunication bus is transmitted only when the lock state of the system is in condition to process the transaction. By monitoring and analyzing bus transactions, the lock state record of each processor is maintained up to date. By thus blocking a transaction involving a locked address before the bus is requested, the tying up of the bus in futile activity is avoided.

Abstract: Each user of an intercommunication bus is associated with a distinct channel of an arbitration bus and maintains a priority record indicating its current priority status against each other user. During a contention interval each user then seeking to use the intercommunication bus bids for use of it by transmitting a bus request signal and makes an analysis of the signals to ascertain if it has dominating priority for initiating a transaction on the bus, and access is granted accordingly. During the use-signal interval a user then using the intercommunication bus transmits an in-use signal used to up-date priority records with the effect of giving the last using user lowest priority. For transactions which require a response from a user other than the one initiating the transaction, a second round of bidding is conducted to determine whether any user is qualified to respond and if so which will be enabled to do so.

Abstract: A computer memory system has multiple memory banks, only one of which can be accessed at any one instant in time. A memory bank decoder determines which of the memory banks is being accessed. The decoded bank enable signals generated by the decoder are used to send memory clocking signals only to the memory bank which is being accessed. In addition, each memory bank includes a clocked address signal buffer and a clocked data signal buffer. Clock signals are sent only to the address and data buffers in the memory bank which is being accessed. As a result, only the selected memory bank has its address and data buffers updated. All the other memory banks remain in a quiescent state, because no control signal, address signals, or data signals are sent to those memory banks.

Abstract: Each user of an intercommunicastion bus is associated with a distinct channel of an arbitration bus and maintains a priority record indicating its current priority status against each other user. During a contention interval each user then seeking to use the intercommunication bus bids for use of it by transmitting a bus request signal and makes an analysis of the signals to ascertain if it has a dominating priority for initiating a transaction on the bus, and access is granted accordingly. During the use-signal interval a user then using the intercommunication bus transmits an in-use signal used to up-date priority records with the effect of giving the last using user lowest priority. For transactions which require a response from a user other than the one initiating the transaction, a second round of bidding is conducted to determine whether any user is qualified to respond and if so which will be enabled to do so.