Address Decoding

Note: The indirect access mechanism must be used only by one interface at a time. When access to the lookup table by multiple masters is possible, it is strongly recommended that the Generic Own bits or some other semaphore mechanism be used to restrict access to one master at a time.

Figure 8. Upstream Lookup Table Address Translation

Primary Address Map

Secondary Address Map

Translated

Base + Offset

Base + Offset

A7466-01

The 21555 conditionally asserts s_inta_l when an upstream memory transaction transfers data addressing the last Dword in a page. This interrupt alerts the local processor that the page entry may need updating. The 21555 implements an event bit and interrupt mask bit for each of the 64 pages (entries) in the upstream window.

Note: The page entry of the lookup table should not be updated while the initiator is still performing transactions addressing that page.

4.3.4Lookup Table Entry Format

Figure 9 shows the format for an entry in the lookup table. The number of bits of the entry used for the new translated base address is variable and is listed in Table 11. The maximum number of bits used are bits [31:8], corresponding to a 256-byte page size, while the minimum number of bits used is bit [31], corresponding to a 32 Mbyte page size. The next 4 to 27 bits, depending on the number of bits used for the base address, are reserved. The low 4 bits are used for control. Two control bits are defined, one indicating whether the entry is a valid entry, and one indicating whether prefetchable behavior should be used on memory reads. When the entry is not valid, the 21555 treats the transaction addressing that page as if a master abort were detected on the target interface.

For writes, the 21555 discards memory write data and asserts s_serr_l, when the SERR# Disable for Master Abort during Posted Write bit is 0. For reads, the 21555 returns FFFFFFFFh on reads if the Master Abort Mode bit is 0, or returns a target abort if the Master Abort Mode bit is a 1.

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Intel 21555 user manual Lookup Table Entry Format, Upstream Lookup Table Address Translation

21555 specifications

The Intel 21555 is a prominent microprocessor developed by Intel, designed to cater to a variety of computing needs. This processor marks a significant step forward in Intel's lineup and underscores the company's commitment to advancing technology in personal computing, enterprise solutions, and beyond.

One of the standout features of the Intel 21555 is its advanced architecture. It utilizes a multi-core design, enabling improved performance through parallel processing. This architecture allows multiple applications to run seamlessly without a decline in speed. The cores are built on a cutting-edge manufacturing process that enhances energy efficiency while maintaining high clock speeds.

The Intel 21555 supports a wide range of technologies, including Intel Turbo Boost, which enables dynamic adjustments to the processor’s performance based on workload demands. This feature allows the processor to accelerate its speed during intensive tasks, providing users with a responsive experience when it matters the most.

Another key characteristic of the Intel 21555 is its support for integrated graphics. With Intel UHD Graphics technology, users can enjoy enhanced visuals for everyday tasks such as video playback, web browsing, and light gaming. This eliminates the need for a separate graphics card for many users, particularly in home office or light gaming scenarios.

Security is a significant focus in the design of the Intel 21555. It includes built-in hardware-based security features like Intel Trusted Execution Technology and Secure Boot. These features help protect against various types of threats, ensuring that user data remains secure from malicious attacks.

The Intel 21555 is also optimized for use with Intel's platform technologies, including Intel Optane memory and Intel Rapid Storage Technology. These technologies work together to deliver faster boot times and improved system responsiveness, making computing more efficient for users.

Furthermore, the Intel 21555 is designed to support virtualization technologies, allowing multiple operating systems to run concurrently without compromising performance. This is particularly useful for developers and businesses that rely on virtualization for testing and development environments.

In summary, the Intel 21555 is a powerful and versatile processor that reflects Intel's ongoing innovation in the computing space. With its multi-core architecture, enhanced graphics capabilities, strong security features, and advanced technologies, it stands out as an excellent choice for a wide range of applications, serving both casual users and professionals alike.