IBM eServer z990 improvements in firmware simulation

With the IBM eServer™ z900, simulation methods and tools for verification of code that is to be embedded in the memory of the system (firmware) were introduced. Since that time, firmware developers have simulated their code prior to the availability of new system hardware components, thereby reducing the time required to bring a large computer system to market. With the z990 system, code simulation efficiency has been improved. The simulation coverage for host and service firmware has been increased from approximately 60% in the z900 to 85% in the z990 by introducing new concepts and extensions. For the first time, the central electronic complex (CEC) firmware simulator, CECSIM, has been enabled to run code in a logical partition (LPAR). This was a prerequisite for code verification of the intra-CEC connectivity, HiperSockets™ For verification of HiperSockets, a Linux® operating system is loaded into an LPAR. Code verification is accomplished more easily, more effectively, and with better coverage using Linux debugging features because of the ease of performing functional tests with Linux. Another major improvement was the connection of the channel code simulator for the networking I/O adapter OSA-Express to the CECSIM environment to provide a comprehensive verification that covers the entire path of firmware interaction between the CEC and the I/O channels. For the simulation of card control code, a combined software and hardware verification approach was introduced. The overall functionality was verified with a system simulation model, and the base hardware accesses were verified by attaching real hardware. In addition, the cage controller code was integrated into the simulation environment. As a result, the firmware interfaces between the support element (SE) and the cage controller as well as between the cage controller and the hardware have been tested.