15.2.6.1.4 Job Preparation

HSM Job Preparation consists of two phases:

  1. Job Creation: JTAG chain setup and device association with programming bitstream.
  2. Add HSM data to the job (adding HSM Task to the job).

Job Creation

Upon creation of a job, the user specifies production type, which can be either FlashPro Express or In- House Programming (IHP). For more information, see, the Job Manager User Guide .

FlashPro Express Job

This job type uses FlashPro Express and the M-HSM in the HSM flow, and is based on the JTAG chain. The JTAG chain may have following types:

  • Microchip device targeted for programing with ​Initiater or Update bit stream.
  • Microchip bypass device not targeted for programming.
  • Non-Microchip bypass device.

Secured IHP Job

General handling of the Secured IHP job type is similar to FlashPro Express Job type. The primary difference is that the Secured IHP job requires only one Microchip device targeted for programming. This is because the actual hardware setup is managed by the IHP system.

Adding HSM Data to the Job through HSM Tasks

The OE can execute a programming job using multiple Contract Manufacturers or by handing off production volume to the Contract Manufacturer in chunks. The OE can manage this by using the HSM Tasks. For example, the OE creates a Programming Job and then creates and exports an HSM Task for each manufacturer.

Following are the main purposes of HSM tasks:

  • Grant permission to execute a job to a specific physical M-HSM in the contract manufacturer's security world.
    • This is a part of the overbuild protection mechanism that excludes the possibility of replicating the job on any other M-HSM in the same security world.
    • A special handshake mechanism between the U-HSM and the M-HSM is designed to accomplish this, as explained later in this section.
  • Enable the OE to limit the number of devices served by a particular programming action (that is, PROGRAM, ERASE, and VERIFY).
    • This is another component of the overbuild protection mechanism.
  • Securely deliver keys and protocol data to the M-HSM for programming execution.

All HSM-related information listed above is handled by Job Tickets associated to the HSM Task. The OE adds the Job Ticket to every authorized programming action (PROGRAM, ERASE, and VERIFY) for the target device. This allows the user to separately manage those actions. The Job Ticket allows control of the overbuild protection mechanism. The OE turns Job Ticket overbuild protection ON or OFF and specifies how many devices the ticket is allowed to handle (for more information, see Job Manager User Guide ).

HSM Task Flow

The following HSM task flow steps must be done by the OE (see Figure 15-41 for details):

  1. Create an HSM Task for the Programming Job.
  2. Create a Job Ticket for the programming bitstream action for the target Microchip programming device:
    • Programming actions that require HSM support need a valid Job Ticket to execute.
    • The maximum number of devices to be allowed for the ticket can be specified in a ticket. The user can select not to turn on overbuild protection for a specific ticket.
  3. The OE executes the Job Request-Reply handshake protocol between the U-HSM and the M-HSM to bind Job Tickets of the HSM Task to the specific physical M-HSM:
    • The OE exports the file with the Job Request from the Job Manager.
    • The OE passes this Job Request to the CM.
      • The OE and CM agree on the transport type for delivering the Job Request, depending on their specific case and security policies.
    • The CM loads the received Job Request with FlashPro Express and M_HSM, and exports a Job Reply.
    • The CM sends the Job Reply file back to the OE.
    • The OE imports the received Job Reply into the HSM Task on the Job Manager side.
  4. The OE generates and exports the HSM Job from the HSM Task and creates the SPPS Programming Job file.
    • The HSM job can only be executed on the physical M-HSM that was used to generate the Job Reply.
    • The generated job is sent to CM for execution.

See Job Manager User Guide for more information about the content of the HSM job file and HSM Task Flow steps.