Abstract: A system includes a non-coherent component; a coherent, non-caching component; a coherent, caching component; and a level two (L2) cache subsystem coupled to the non-coherent component, the coherent, non-caching component, and the coherent, caching component. The L2 cache subsystem includes a L2 cache; a shadow level one (L1) main cache; a shadow L1 victim cache; and a L2 controller. The L2 controller is configured to receive and process a first transaction from the non-coherent component; receive and process a second transaction from the coherent, non-caching component; and receive and process a third transaction from the coherent, caching component.

Abstract: In described examples, a processor system includes a processor core generating memory transactions, a lower level cache memory with a lower memory controller, and a higher level cache memory with a higher memory controller having a memory pipeline. The higher memory controller is connected to the lower memory controller by a bypass path that skips the memory pipeline. The higher memory controller: determines whether a memory transaction is a bypass write, which is a memory write request indicated not to result in a corresponding write being directed to the higher level cache memory; if the memory transaction is determined a bypass write, determines whether a memory transaction that prevents passing is in the memory pipeline; and if no transaction that prevents passing is determined to be in the memory pipeline, sends the memory transaction to the lower memory controller using the bypass path.

Abstract: An integrated circuit comprises a set of processor cores, wherein each processor core of the set of processor cores includes BIST logic circuitry and multiple memory blocks coupled to the BIST logic circuitry. Each processor core further includes multiple power control circuitry, where each power control circuitry of the multiple power control circuitry is coupled to a respective processor core of the set of processor cores, multiple isolation circuitry, where each isolation circuitry of the multiple isolation circuitry is coupled to a respective processor core of the set of processor cores, a built-in-self repair (BISR) controller coupled to the each of the set of processor cores, each of the multiple power control circuitry, and each of the multiple isolation circuitry, and a safety controller coupled to the BISR controller, the multiple power control circuitry, and to the multiple isolation circuitry.

Abstract: An apparatus includes a central processing unit (CPU) core and a cache subsystem coupled to the CPU core. The cache subsystem includes a first memory, a second memory, and a controller coupled to the first and second memories. The controller is configured to execute a sequence of scrubbing transactions on the first memory and execute a functional transaction on the second memory. One of the scrubbing transactions and the functional transaction are executed concurrently.

Abstract: A method includes receiving, by a level two (L2) controller, a first request for a cache line in a shared cache coherence state; mapping, by the L2 controller, the first request to a second request for a cache line in an exclusive cache coherence state; and responding, by the L2 controller, to the second request.

Abstract: An apparatus includes a CPU core, a first memory cache with a first line size, and a second memory cache having a second line size larger than the first line size. Each line of the second memory cache includes an upper half and a lower half. A memory controller subsystem is coupled to the CPU core and to the first and second memory caches. Upon a miss in the first memory cache for a first target address, the memory controller subsystem determines that the first target address resulting in the miss maps to the lower half of a line in the second memory cache, retrieves the entire line from the second memory cache, and returns the entire line from the second memory cache to the first memory cache.

Abstract: A system comprises a processor including a CPU core, first and second memory caches, and a memory controller subsystem. The memory controller subsystem speculatively determines a hit or miss condition of a virtual address in the first memory cache and speculatively translates the virtual address to a physical address. Associated with the hit or miss condition and the physical address, the memory controller subsystem configures a status to a valid state. Responsive to receipt of a first indication from the CPU core that no program instructions associated with the virtual address are needed, the memory controller subsystem reconfigures the status to an invalid state and, responsive to receipt of a second indication from the CPU core that a program instruction associated with the virtual address is needed, the memory controller subsystem reconfigures the status back to a valid state.

Abstract: In described examples, a processor system includes a processor core that generates memory write requests, a cache memory, and a memory pipeline of the cache memory. The memory pipeline has a holding buffer, an anchor stage, and an RMW pipeline. The anchor stage determines whether a data payload of a write request corresponds to a partial write. If so, the data payload is written to the holding buffer and conforming data is read from a corresponding cache memory address to merge with the data payload. The RMW pipeline has a merge stage and a syndrome generation stage. The merge stage merges the data payload in the holding buffer with the conforming data to make merged data. The syndrome generation stage generates an ECC syndrome using the merged data. The memory pipeline writes the data payload and ECC syndrome to the cache memory.

Abstract: An apparatus includes a CPU core, a first cache subsystem coupled to the CPU core, and a second memory coupled to the cache subsystem. The first cache subsystem includes a configuration register, a first memory, and a controller. The controller is configured to: receive a request directed to an address in the second memory and, in response to the configuration register having a first value, operate in a non-caching mode. In the non-caching mode, the controller is configured to provide the request to the second memory without caching data returned by the request in the first memory. In response to the configuration register having a second value, the controller is configured to operate in a caching mode. In the caching mode the controller is configured to provide the request to the second memory and cache data returned by the request in the first memory.

Abstract: In described examples, a processor system includes a processor core generating memory transactions, a lower level cache memory with a lower memory controller, and a higher level cache memory with a higher memory controller having a memory pipeline. The higher memory controller is connected to the lower memory controller by a bypass path that skips the memory pipeline. The higher memory controller: determines whether a memory transaction is a bypass write, which is a memory write request indicated not to result in a corresponding write being directed to the higher level cache memory; if the memory transaction is determined a bypass write, determines whether a memory transaction that prevents passing is in the memory pipeline; and if no transaction that prevents passing is determined to be in the memory pipeline, sends the memory transaction to the lower memory controller using the bypass path.

Abstract: An apparatus includes a CPU core, a first memory cache with a first line size, and a second memory cache having a second line size larger than the first line size. Each line of the second memory cache includes an upper half and a lower half. A memory controller subsystem is coupled to the CPU core and to the first and second memory caches. Upon a miss in the first memory cache for a first target address, the memory controller subsystem determines that the first target address resulting in the miss maps to the lower half of a line in the second memory cache, retrieves the entire line from the second memory cache, and returns the entire line from the second memory cache to the first memory cache.

Abstract: A method includes receiving, by a first stage in a pipeline, a first transaction from a previous stage in pipeline; in response to first transaction comprising a high priority transaction, processing high priority transaction by sending high priority transaction to a buffer; receiving a second transaction from previous stage; in response to second transaction comprising a low priority transaction, processing low priority transaction by monitoring a full signal from buffer while sending low priority transaction to buffer; in response to full signal asserted and no high priority transaction being available from previous stage, pausing processing of low priority transaction; in response to full signal asserted and a high priority transaction being available from previous stage, stopping processing of low priority transaction and processing high priority transaction; and in response to full signal being de-asserted, processing low priority transaction by sending low priority transaction to buffer.

Abstract: In described examples, a processor system includes a processor core that generates memory write requests, and a cache memory with a memory controller having a memory pipeline. The cache memory has cache lines of length L. The cache memory has a minimum write length that is less than a cache line length of the cache memory. The memory pipeline determines whether the data payload includes a first chunk and ECC syndrome that correspond to a partial write and are writable by a first cache write operation, and a second chunk and ECC syndrome that correspond to a full write operation that can be performed separately from the first cache write operation. The memory pipeline performs an RMW operation to store the first chunk and ECC syndrome in the cache memory, and performs the full write operation to store the second chunk and ECC syndrome in the cache memory.

Abstract: An apparatus includes a central processing unit (CPU) core and a cache subsystem coupled to the CPU core. The cache subsystem includes a first memory, a second memory, and a controller coupled to the first and second memories. The controller is configured to receive a transaction from a master, the transaction directed to the first memory and comprising an address; re-calculate an error correcting code (ECC) for a line of data in the second memory associated with the address; determine that a non-correctable error is present in the line of data in the second memory based on a comparison of the re-calculated ECC and a stored ECC for the line of data; and in response to the determination that a non-correctable error is present in the line of data in the second memory, terminate the transaction without accessing the first memory.

Abstract: An apparatus includes a CPU core, a first cache subsystem coupled to the CPU core, and a second memory coupled to the cache subsystem. The first cache subsystem includes a configuration register, a first memory, and a controller. The controller is configured to: receive a request directed to an address in the second memory and, in response to the configuration register having a first value, operate in a non-caching mode. In the non-caching mode, the controller is configured to provide the request to the second memory without caching data returned by the request in the first memory. In response to the configuration register having a second value, the controller is configured to operate in a caching mode. In the caching mode the controller is configured to provide the request to the second memory and cache data returned by the request in the first memory.

Abstract: In described examples, a processor system includes a processor core that generates memory write requests, and a cache memory with a memory controller having a memory pipeline. The cache memory has cache lines of length L. The cache memory has a minimum write length that is less than a cache line length of the cache memory. The memory pipeline determines whether the data payload includes a first chunk and ECC syndrome that correspond to a partial write and are writable by a first cache write operation, and a second chunk and ECC syndrome that correspond to a full write operation that can be performed separately from the first cache write operation. The memory pipeline performs an RMW operation to store the first chunk and ECC syndrome in the cache memory, and performs the full write operation to store the second chunk and ECC syndrome in the cache memory.

Abstract: An apparatus includes first CPU and second CPU cores, a L1 cache subsystem coupled to the first CPU core and comprising a L1 controller, and a L2 cache subsystem coupled to the L1 cache subsystem and to the second CPU core. The L2 cache subsystem includes a L2 memory and a L2 controller configured to operate in an aliased mode in response to a value in a memory map control register being asserted. In the aliased mode, the L2 controller receives a first request from the first CPU core directed to a virtual address in the L2 memory, receives a second request from the second CPU core directed to the virtual address in the L2 memory, directs the first request to a physical address A in the L2 memory, and directs the second request to a physical address B in the L2 memory.

Abstract: A method includes receiving, by a first stage in a pipeline, a first transaction from a previous stage in pipeline; in response to first transaction comprising a high priority transaction, processing high priority transaction by sending high priority transaction to a buffer; receiving a second transaction from previous stage; in response to second transaction comprising a low priority transaction, processing low priority transaction by monitoring a full signal from buffer while sending low priority transaction to buffer; in response to full signal asserted and no high priority transaction being available from previous stage, pausing processing of low priority transaction; in response to full signal asserted and a high priority transaction being available from previous stage, stopping processing of low priority transaction and processing high priority transaction; and in response to full signal being de-asserted, processing low priority transaction by sending low priority transaction to buffer.

Abstract: In described examples, a coherent memory system includes a central processing unit (CPU) and first and second level caches. The memory system can include a pipeline for accessing data stored in one of the caches. Requestors can access the data stored in one of the caches by sending requests at a same time that can be arbitrated by the pipeline.

Abstract: An apparatus includes a central processing unit (CPU) core and a cache subsystem coupled to the CPU core. The cache subsystem includes a first memory, a second memory, and a controller coupled to the first and second memories. The controller is configured to receive a transaction from a master, the transaction directed to the first memory and comprising an address; re-calculate an error correcting code (ECC) for a line of data in the second memory associated with the address; determine that a non-correctable error is present in the line of data in the second memory based on a comparison of the re-calculated ECC and a stored ECC for the line of data; and in response to the determination that a non-correctable error is present in the line of data in the second memory, terminate the transaction without accessing the first memory.