Marvell International Limited

Michael R Spaur

Raymond A Sandoval

Larry L Byers

David M Purdham

Ihn Kim

Kevin Kwan

Gary R Robeck

Joseba M Desubijana

Paul B Ricci

Joseph G Kriscunas

A servo controller includes a first device that determines an adjusted servo-to-servo skew value. A servo field timer increments a timer value between consecutive servo fields, receives the adjusted servo-to-servo skew value, and adjusts an incremented timer value between the consecutive servo fields based on the adjusted servo-to-servo skew value.

Method and system for automatic time base adjustment for disk drive servo controllers

A track follow controller includes a burst selector selecting at least one burst pair based on burst pair selection data. A linear position calculator calculates a primary head position and a secondary head position based on the at least one burst pair, and calculates a head linear position based on the primary head position and the secondary head position.

Method and system for head position control in embedded disk drive controllers

A system-on-chip including a processor, a control module, a first plurality of data registers, a second plurality of data registers, a plurality of address registers, and a first control module. The first plurality of data registers are configured to store data. The processor is configured to respectively write addresses corresponding to selected ones of the first plurality of data registers in the plurality of address registers. The second plurality of data registers are configured to receive data from the selected ones of the first plurality of data registers. In response to a request from the processor for a first address, the first control module is configured to provide data to the processor from the second plurality of data registers in response to the first address matching an address stored in the plurality of address registers, and otherwise provide data to the processor from the first plurality of data registers.

Communication bus with hidden pre-fetch registers

A servo controller for a disk drive controller comprising a storage device that stores communication information for a plurality of devices and a serial port controller located on the servo controller that communicates with the storage device, that receives a request to communicate with one of the plurality of devices, and that allows communication between at least one processor and the one of the plurality of devices according to the stored communication information and the request, wherein each of the plurality of devices uses a different protocol.

Method and system for supporting multiple external serial port devices using a serial port controller in embedded disk controllers

An embedded disk controller ('controller') having a servo controller is provided. The controller also includes a servo controller interface with a speed matching module and a pipeline control module such that at least two processors share memory mapped registers without conflicts. The processors operate at different frequencies, while the servo-controller and the servo controller interface operate in same or different frequency domains. The pipeline control module resolves conflict between the first and second processor transaction. The speed matching module ensures communication without inserting wait states in a servo controller interface clock domain for write access to the servo controller and there is no read conflicts between the first and second processor. The controller also includes a hardware mechanism for indivisible register acess to the first or second processor. The hardware mechanisim includes a hard semaphore and/or soft semaphore.

Servo controller interface module for embedded disk controllers

A system-on-chip (SOC) includes a processor, a controller module for a hard disk drive, and a communication bus that provides a communication link between the processor and the controller module. The communication bus includes a multiplexer that includes an output and an input that receives data from a selected one of N registers associated with the controller module and propagates the data to the output, M address registers that store addresses of up to M ones of the N registers, M data registers that receive pre-fetch data that corresponds to the data from the output from the M ones of the N registers, and a second multiplexer that includes a second output and that reads the pre-fetch data from the M data registers and propagates the pre-fetch data to the second output. M and N are positive integers greater than two and N is greater than M.

A system and method for a servo controller (SC) used in an embedded disk controller for adjusting stored servo skew values based on measured skew values is provided. The system includes, a servo timing controller, wherein the servo timing controller includes a first register that stores measured servo skew values at a given time; a first set of registers that receive stored skew values and the measured skew values; and firmware that adjusts the skew values based on the measured skew values measured by a reference timer. The process includes, measuring actual skew values during a head change in a read operation; comparing the measured skew values with the stored skew values; adjusting the skew value based on the comparison; and adjusting a servo field timer based on the adjusted skew value.

A position error calculator for an embedded disk controller including a burst selector that selects a burst pair based on a burst pair format. The burst pair format includes at least a first burst pair format that includes x bursts and a second burst pair format that includes y bursts and x is not equal to y. A linear position calculator calculates head linear position based on the burst pair format.

A servo controller for an embedded disk controller comprises a read channel interface that includes a programmable control logic that receives a servo field detected signal from a module that detects a servo field start bit. A memory in the read channel interface is enabled by the programmable control logic for receiving servo field data from a read channel device, wherein the programmable control logic is configured to operate in a first mode and a second mode allowing the servo controller to process servo data from the read channel device. The servo controller processes the servo data using first and second data widths during the first and second modes, respectively.

Method and system for collecting servo field data from programmable devices in embedded disk controllers

A track follow controller ('TFC') in an embedded disk controller is provided. The TFC includes, a position error calculator that determines a linear position of a head based on burst format and determines a position error based on the linear position and a target position; and a position error output compensator that receives a position error signal from the position error calculator and filters the position error signal. The burst format includes at least a first burst pair format that includes x bursts and a second burst pair format that includes y bursts, where x is unequal to y. The position error calculator includes a burst selector that can select a burst pair; a linear position calculator that calculates head linear position based on burst pair format; and an error calculator that determines the position error based on the linear position and target position.

A system for an embedded disk controller is provided. The system includes a first main processor operationally coupled to a high performance bus; a second processor operationally coupled to a peripheral bus; a bridge that interfaces between the high performance and peripheral bus; an external bus controller coupled to the high performance bus and operationally coupled to external devices via an external bus interface; an interrupt controller module that can generate a fast interrupt to the first main processor; a history module coupled to the high performance and peripheral bus for monitoring bus activity; and a servo controller that is coupled to the second processor through a servo controller interface and provides real time servo controller information to the second processor. The second processor may be a digital signal processor that is operationally coupled to the first main processor through an interface.

Method and system for embedded disk controllers

A system for collecting servo field data from programmable devices in embedded disk controllers. The system includes a servo controller with a read channel interface. The read channel interface includes a programmable control logic that receives a servo field detected signal from a module that detects a servo field start bit; and a register in the read channel interface that is enabled by the programmable control logic for receiving servo field data from a read channel device. The programmable control logic is configured to operate both in a two wire mode and in a three wire mode allowing the servo controller to process servo data from the read channel device.

A serial port controller in an embedded disk drive controller is provided. The serial port controller includes a state machine that can access protocol information regarding plural devices operationally coupled to the serial port controller; a first register that can hold address information of the plural devices; and logic for enabling the plural devices for either a write or read request. The serial port controller also includes a second register for holding write data information for the plural devices; and a third register for holding read data information for the plural devices. The serial port controller reads programmed information regarding the plural device upon a client request; transmits the address of a device with whom communication is requested by the client; and transmits data to the plural devices, if the request by the client is to write data or collects data for a read request.

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Dana Point, CA, United States of America

Michael R Spaur